U-^^ . OoclmX <^Oc5-v'200 meters) of the Kara Sea, composed almost entirely of terrigenous elas- tics, are predominantly silty clay which is very poorly sorted, near-symmetrical to coarse-skewed and mesokurtic. The clay minerals are kaolinite, chlorite, illite, an expandable component which is probably montmorillonite, and possibly some mixed layer clays. The upper layers in many cores display a color sequence from the surface downward of light brown to dark brown to yellow- brown to gray-green to brown to gray-green. No significant textural or mineralogical difference exists between brown layers and gray-green ones. In two cores non-detrital iron and man- ganese are greatly enriched in the brown surface layers but not at the same stratigraphic level. The highest concentration of non-detrital manganese occurs several centimeters nearer to the sediment-water interface than does the highest concen- tration of non-detrital iron. Beneath the surface layers the concentration of both elements is greatly reduced except in the secondary brown layers which are somewhat enriched in non-detrital iron and very slightly in non-detrital manganese. Non-detrital material isolated from the upper manganese- and iron-enriched layers gave no diagnostic X-ray diffraction patterns and is probably amorphous or crypto-crystalline. Co- prolitic material from one secondary brown layer was identi- fied as the iron phosphate, vivianite. The concentration of non-detrital iron in 98 surface samples generally increases toward the mouths of the Siberian rivers, suggesting that these are the sources of iron in the Kara Sea. The distribution of non-detrital manganese in surface sediments apparently is controlled by factors other than distance from source. The non-detrital Mn/Fe ratio generally increases away from the river mouths, suggesting that iron is deposited nearer the points of influx than manganese. The distribution of non-detrital iron and manganese with depth in the cores appears to the controlled by post-depositional processes, including dissolution, migration, and subsequent dif- ferential oxidation of iron and manganese ions, rather than by primary depositional processes or variability in the rate of influx. CONTENTS Pase Title page i Abstract iii Table of contents v List of illustrations v Introduction 1 Purpose 1 Location and physical characteristics 1 Geological setting 2 Previous work 2 Procedures 4 Field methods 4 Laboratory methods 4 Statistical methods 5 Results 6 Color 6 Texture 6 Mineralogy 7 Vertical distribution of nondetrital iron and manganese 7 Regional distribution of nondetrital iron and manganese 7 Discussion 8 Conclusions 12 Acknowledgment 13 References 13 Illustrations 16 Tables 27 Illustrations Figure Page 1. Physiography and circulation pattern of the Kara Sea 16 2. Redox potential and pH in two KNIPOVICH cores from the Kara Sea 17 3. Station locations and bathymetry 18 4. Color variations with depth in 10 cores from the northern Kara Sea 19 5. Color variations and distribution of gravel, sand, silt and clay with depth in cores from stations E-8 and E-11 ( Svyataya Anna Trough) 20 6. Color variations and distribution of gravel, sand, silt and clay with depth in cores from stations E-21, E-22, E-25, and E-26 ( East Novaya Zemlya Trough) 21 7. Color variations and distribution of gravel, sand, silt and clay with depth in cores from stations E-28, E-29, E-30, E-31 (East Novaya Zemlya Trough) 22 8. Distribution of nondetrital iron and manganese and color in core E-26 and N-148 23 9. Percent Nondetrital iron in surface sediments (Linear trend surface) 24 Pace 10. Percent nondetrital manganese in surface sediments (linear trend surface) 25 11. Nondetrital Mn/Fe ratio in surface sediments (linear trend surface) 26 Tables Table Page 1. Profile of a typical core from the Kara Sea 27 2. Percent of major clay groups and peak area ratios for cores E-26 and E-21 27 3. Means and standard deviations for nondetrital iron, man- ganese, and Mn/Fe ratio in the surface sediments for each deeper extractable iron, manganese, and Mn/Fe ratio in the surface sediments of the southwestern Kara Sea 27 4. Distribution of manganese and iron oxides in secondary microzonal profile of mud from Lake Valk-Yarvi 28 5. Station positions and water depths for Northwind (1965) sediment samples 28 6. Station positions and water depths for Edisto-Eastwind (1967) sediment samples 28 7. Core descriptions (E-Series) 29 8. Gravel, sand, silt and clay percentages 32 9. Textural parameters 32 10. X-ray diffraction data for black crusts from core E-26, 3-7 cm and for brown earthy material from core E-26, 7-10 cm 33 11. Comparison of X-ray data for pellets separated from core E-31, 20-23 cm, with data for the mineral vivianite 34 12. Distribution of nondetrital iron and manganese in core E-26 ^ . 34 13. Distribution of nondetrital iron and manganese in core N-148 35 14. Nondetrital iron and manganese in surface sediments 35 15. HCI-extractable iron and manganese in surface sediments of southwestern Kara Sea 36 VI THE SIGNIFICANCE OF COLOR BANDING IN THE UPPER LAYERS OF KARA SEA SEDIMENTS Ralph R. Turner' Introduction Purpose Geological investigations of much of the Kara Sea have been limited by inaccessibility to all but icebreakers and by diplomatic consid- erations because of its strategic position north of Western Siberia. In spite of these limita- tions, two reconnaissance surveys have been conducted by United States icebreakers (USCGC Northwind. 1965; USCGC Edisto and USCGC Eashvind, 1967). In compliance with the Continental Shelf Treaty of 1961 (signed by the United States in 1964), bottom sam- pling during these surveys was limited to water depths in excess of 200 meters. The pres- ent study was undertaken to evaluate the tex- tural, mineralogical, and geochemical signifi- cance of remarkably similar color sequences displayed in the upper layers of sediment cores collected. Location and Physical Characteristics The Kara Sea is located on the Arctic Eur- asian Continental Shelf between Zemlya Frantsa losifa and Severnaya Zemlya archipel- agos and extends southward along the east coast of Novaya Zemlya to the Eurasian coast (fig. 1). It is the westernmost of the series of Arctic epicontinental marginal seas lying along the northern shores of Siberia. The area of the Kara Sea is 883,000 km.= of which only 190,000 km.- exceeds 200 meters in water depth. This deeper water is restricted to two north-facing reentrants, or troughs, in the northern part of the sea and to a 740-km. ar- cuate trough parallel to and convex towards Novaya Zemlya. The greatest depth (approxi- mately 600 m.) occurs in the western reen- trant, Svyataya Anna Trough, at the northern extremity. The other two troughs, Voronin and Novaya Zemlya, have depths up to 430 m. (Northivind sounding). A glacial erosion ori- gin has been suggested for all three troughs on the basis of their geomorphology and geo- graphic location (Johnson and Milligan, 1967). A striking physical feature of the Kara Sea is a well-developed deltaic system which ex- tends some 300 km. seaward of the river mouths in the southern part of the sea (John- son and Milligan, 1967) Delta development in this region is not surprising considering the large annual discharge of suspended matter (30 x 10^ tons, Kulikov, 1961) from the Ob and Yenisey Rivers which debouch into the Kara Sea from the south. The Central Kara Plateau which extends northward between the Svyataya Anna and Vorinin Troughs is not part of the deltaic system but is overlapped by it at 79° N. (Johnson and Milliean, 1967). The two small islands, Vize and Ushakova, are on this plateau. In spite of the summer stratification, the depths of the deeper troughs remain well ven- tilated. Data from Garcia (1969) showed values for dissolved oxygen during the summer no lower than 6.15 ml. liter for the deepest water samples from the East Novaya Zemlya Trough. Water which originates in the Atlantic Ocean, called Atlantic water, (T>0° C. S>34 °/„o) also enters the Kara Sea via sev- eral pathways. Off the northern tip of Novaya Zemlya, Atlantic Water which has transited the Barents Sea continues westward into the Kara Sea where it largely mixes with both the continental runoff and Arctic water (T<-1.5° C, S = 33.5 to 34.5''/„o; Milligan, 1969K Atlantic water, considerably midified by transit along the continental slope north of Spitsbergen and Zemlya Frantsa losifa, also enters the Kara Sea through the St. Anna and Voronin Troughs. According to Milligan (1969) this subsurface flow is a counterflow to the north- ward flowing continental runoff. A trivial amount of Atlantic water also penetrates the Kara Sea through the straits between Novaya Zemlya and the Siberian mainland (Zenkevitch, 1963; Milligan, 1969). Other water masses present in the Kara Sea include Arctic water, which is probably formed by mixing of the continental runoff and Atlan- tic water, and Arctic bottom water (T<0° C, S>34.0° "/„„) which enters the deepest depth of the Svyataya Anna and Voronin Troughs as a compensatory flow to the outflowing continen- tal runoff (Milligan, 1969). Sea ice begins to form in the Kara Sea as early as September and melting starts only in June but ice cover even in midwinter is not solid or continuous (Zenkevitch, 1963). The ice that is formed off the Siberian coast and in the rivers, and icebergs calved from the relict gla- ciers on the north island of Novaya Zemlya, are carried by the cyclonic surface circulation into the lee of Novaya Zemlya, where they per- sist even into the summer (Nordenskjold and Mecking, 1928). Geological Setting The Kara Sea is situated amid rocks from nearly every geologic period. Precambrain shield, consisting mostly of gneisses and schists, is exposed on the northern shore of Taymyr Peninsula, the southwestern part of Severnaya Zemlya archipelago and several offshore islands (Rabkin and Ravich, 1961). Slightly metamorphosed and folded Paleozoic rocks, predominantly carbonates and elastics, compose Novaya Zemlya, the western islands of Severnaya Zemly archipelago and much of the Yugorskiy Peninsula (Markov and Tkach- enko. 1961). Mesozioc deposits occupy Zemlya Frantsa losifa and the islands Ushakova and Vize and consist mostly of friable elastics with considerable organic remains including coal (Dibner, 1957). The region between Yugorskiy and Taymyr Peninsulas, termed the West Sibe- rian Lowlands, is blanketed by a thick cover of unconsolidated Quaternary deposits (Saks, 1948). The tectonics of the Kara Sea are complex and not completely worked out, but several de- tails are clear. Novaya Zemlya and Vaigach Is- land, which lies between Novaya Zemlya and the Soviet mainland, are a tectonic continua- tion of a mainland axis which branches off lat- erally from the northern end of the Urals (Nordenskjold and Mecking, 1928). Tectonic trends also connect the northern border of Taymyr and the Severnaya Zemlya archipelago (Nalivkin, 1960) and are probably connected with the Ural trend. Many of the islands and the floor of the Kara Sea are marked by numerous abrasional terraces which reflect the complex glacial and postglacial history of this region. Novaya Zem- lya and the Taymyr-Severnaya Zemlya region were principal centers of glaciation which progressed over a considerable part of the Rus- sian plain (Saks, 1948; Saks and Strelkov, 1961). Saks (1948) concluded that tectonic pulsations in the northern part of Eurasia dur- ing the Quaternary rather than eustatic and isostatic factors were largely responsible for the oscillations in the coastal contours. None- theless the beds of the Ob and Yenisey Riv- ers can be traced to a depth of 100 meters in the Kara Sea (Saks, 1948) and there are many deltaic channels within a 35 to 70 meter depth range on the continental shelf which Johnson and Milligan (1967) favored as being relicts of a lower sea level. The shore structure of No- vaya Zemlya, on the other hand, is defined by ascending vertical movements (Zenkovitch, Leontiev, and Nevessky, 1960) and the rivers of Western Siberia appear to be "entrenched" rather than "drowned" (Lazukov, 1964). The conflicting evidence of sea level fluctuations in the Kara Sea has been reviewed and illustrated by Lazukov (1964, see esp. fig. 1). Previous Work Klenova (1936) first outlined the general sediment distribution in the southwestern Kara Set. She observed that the sediments in all the deeper areas were predominantly silty clay or mud (over 50 percent less than 0.01 mm.) and terrigenous silt of glacial marine or- igin and were brown in color in the upper lay- ers. She also noted that the sediment texture tended to reflect the cyclonic rotation of sur- face water in the southwestern part of the Kara Sea which permitted mud to accumulate in quite shallow water. Klenova (1938) suggested that iron and man- ganese oxides were responsible for the brown color in the upper layers of Kara Sea sedi- ments and that the stability of these oxides, and hence the color of the sediments, was de- pendent on the amount of dissolved oxygen in bottom and sediment interstitial waters and or- ganic matter in the sediments. Brujevicz (1938a,6) and Trofimov (1939) measured the redox potential (Eh) and pH with depth in several Kara Sea cores. Trofimov (1939) observed a transition from oxidizing to reducing conditions on entering subsurface gray-green layers and a corresponding sharp decrease in the pH at the boundary between oxidizing and reducing conditions (fig. 2). He proposed that isolation of strata from oxygen- ated bottom waters by burial and consumption of oxygen in interstitial water by oxidation of organic matter produced the redox potential and PH profiles. The sharp decrease in pH at the boundary between oxidizing and reducing conditions was attributed to hindered removal of the CO2 produced in the oxidation of or- ganic matter. Brujevicz (1938a, 6) predicted a separation of the more mobile phases of iron and manganese in response to the gradient in redox potential between buried strata and the sediment-water interface. Klenova and Pakhomova (1940) observed an increase in the content of manganese with de- creasing grain size in Kara Sea sediments, with clayey muds averaging 1.2 percent by weight manganese. They also noted that the highest content of manganese (3.5 percent) oc- curred in dark brown (chocolate) sediments and these occurred in regions where the salin- ity gradient between surface and bottom water was the greatest. Yermolayev (1948a,6) has characterized the typical physical features of Recent Kara Sea stratigraphy (table 1). He proposed that non- uniform lithogenetic processes associated with microorganisms and the hydrological regime have operated to produce the physical and chemical properties observed in Kara Sea cores. The processes are nonuniform according to Yermolayev because aerobic conditions pre- vail in some layers (upper brown) and anaero- bic conditions prevail in others (subsurface gray-green) and because the hydrology of the Kara Sea has undergone changes in the recent geologic past in response to periodic influx of warm Atlantic waters at intermediate depths. He observed a direct correlation between the thickness of the warm intermediate Atlantic water and the thickness of oxidized (brown) bottom sediments in the Arctic seas and polar basin and suggested that the secondary (bur- ied) brown layers were generated during pe- riods of maximum influx of Atlantic water. Ac- cording to Yermolayev these periods would be characterized by well ventilated bottom waters in response to the increased surface and inter- mediate circulation which would favor oxida- tion and retention of ferromanganese com- pounds in the sediments. The finding by Belov and Lapina (1959) of increased amounts of ferric and manganese oxides in Arctic basin sediments deposited during periods of influx of warm Atlantic waters into the Arctic Ocean lends some support to Yermolayev's hypothe- sis. The results of an experiment conducted by Yermolayev (1948a,&) shed considerable light on the nature of the stability of the secondary brown layers and the reversibility of aerobic- anaerobic processes. When a typical core (table 1) from the Kara Sea was inverted, i.e., placed such that the brown layers (la, 16, Ic) were sealed oflF from exchange with overlying water and the gray-green layers exposed to exchange with the overlying water, the brown layers were transformed to gray-green layers and the gray-green layers transformed to brovni layers after a period of 17 months. The exception to this was that the bright orange layer (Ic) did not transform. This layer and the lower brown layer (116) were designated "zones of lithogenesis" by Yermolayev and possessed the highest Fe'^*/Fe=+ ratio (20- 25). He demonstrated that bacteria were largely responsible for this transformation by repeating the experiment with sterilized sedi- ment. In this case the transformation was con- siderably retarded, if not halted completely. He concluded that bacteria played a considera- ble role, even if indirect, in determining the physical characteristics of Kara Sea sediments. Gorshkova (1957) outlined in detail the tex- tural, mineralogical and geochemical charac- teristics of Kara Sea sediments both regionally and with depth in cores. She also concluded that the color of Kara Sea sediments depended largely on their ferromanganese content and demonstrated that sediment color and benthic biomass were closely related. Gorshkova (1966) suggested that the large accumulations of mangancjc in Kara Sea sedi- ments were attributable to the semiclosed con- figuration of the coastal zone of the Kara Sea which, coupled with the great quantity of man- ganese brought in by the inflowing rivers fa- vored the vital activities of microorganisms and the biochemical settling of manganese. Nesterova (1960) investiagted the chemical composition of the suspended and dissolved loads of the Ob River which enters the Kara Sea from the south and found that Fe, Mn, P and other minor elements are transported largely in mechanical suspension and only partly in solution. Strakhov ( 1966, using the data of Nerterova (1960) for the chemical composition of Ob River water and the data of Gorshkova (1957) for the composition of Kara Sea sediments, found more iron and manganese in the surface sediments of the Kara Sea than could be ac- counted for by river input alone. He attributed the excess to the migration of iron and manga- nese from the reducing zone of gray and gray- green sediment layers to the oxidizing zone of the brown upper layers. Kulikov (1961) observed that the highest iron and manganese concentrations were in clayey sediments and in areas of the Kara Sea where Ob and Yenisey river water is found. He also noted a tendency for iron and manganese to concentrate in trough and depression sedi- ments. Kulikov (1961) reported that in the Kara Sea the mineralogical composition varies rela- tively little with depth in sediment cores. Heavy minerals may constitute as much as 10 percent of the 50 to 100 micron fraction (Gor- shkova, 1957; Kulikov, 1961). According to Kulikov, amphibole, pyroxene, epidote and dark ore minerals in varying proportions make up the bulk of the heavy fractions. The light fractions contain predominantly quartz (60 to 80 percent), orthoclase (20 to 30 percent, sometimes 40 to 60 percent), and plagioclase (5 to 20 percent). The clay fractions contain up to 70 percent hydromica. Estimates of rates of sedimentation for the deeper areas of the Kara Sea based on both radium concentrations and clastic inputs to the Kara Sea (Yermolayev, 1948a,b; Saks, 1953, cited in Kulikov, 1961 ) range from 4 to 6 cm. per thousand years. The rate of sedimentation within the boundaries of the Ob- Yenisey shal- lows (<50 m.) varies from 30 to 100 cm. per thousand years (Saks, 1953, cited in Kulikov, 1961). Procedures Field The cores from the CGC Northwind survey from which surface samples were cut for this study were obtained with a Kullenberg gravity corer. The cores from the CGC Edisto-CGC Eastwind survey (fig. 3) were obtained with a Phleger corer. Cores from both surveys were retained in plastic liners and were stored at low temperature (above freezing) to reduce bacterial activity. Sediment samples remaining after the analyses described below are availa- ble on request from the author at the Depart- ment of Oceanography, Florida State Uni- versity, Tallahassee, Fla. 32306, and after August, 1971, from the Smithsonian Oceano- graphic Sorting Center, Washington, D.C. 20390. Laboratory In the laboratory the cores were split longi- tudinally, described (table 7) and sampled. Surface samples from 42 Northwind cores and 5 grab samples were obtained from the Univer- sity of Wisconsin, Geophysical and Polar Research Center, and were used for the geo- chemical analyses. In addition core N-148 was sampled at 1-cm. intervals for the geochemical sampled at 10-cm., 5-cm., or shorter intervals for grain size analyses and at 1-cm intervals for the geochemical analyses. With the excep- tion of core E-26 which was studied in detail, only the top centimeter of each core was used for the geochemical studies. The samples cut from the CGC Edisto-CGC Eastwind survey cores for grain size analyses averaged 5 to 15 grams dry weight and were sized using standard sieving and pipette proce- dures (Folk, 1965). Grain size analyses on the CGC Northwind cores have been conducted by the U.S. Naval Oceanographic Office (Andrew and Kravitz, 1968) . Because 71 of 88 samples {Edi^- to-Eastivind) analyzed for grain size distribu- tion contained more than 90 percent clay-and silt-sized material with the larger proportion being clay-sized, X-ray examination of the clay-sized (<4 microns) was more appro- priate than optical studies of the coarse (sand-sized) fractions (>62 microns). In ad- dition, preliminary analyses revealed that heavy minerals (S.G. greater than 2.95) made up only about 1 percent of the 62-250 micron fraction in eight surface samples from the East Novaya Zemlya Trough. Thus coarse fraction mineralogy of sediments from the deeper troughs may not be truly representative of the total sediment mineralogy. Samples from both brown and gray-green layers were selected from cores E-21 and E-26 for the clay mineralogy studies. The clay-sized fraction was separated by settling and oriented slides were prepared by air-drying aliquots on glass slides. The error in quantitative determi- nations introduced by this mounting technique (Gibbs, 1965) renders the results reported here at best semiquantitative. The slides were X-rayed using Ni-filtered Cuka radiation from 2° to 30° 28. Each slide was X-rayed again after treatment with ethylene glycol to reveal expandable components. No attempt was made to distinguish chlorite from koalinite al- though both were present in all samples as evi- denced by a broad, often double peak at 3.53 to 3.57 A. Peak areas for the basal (001) reflec- tions were measured and used to make semi- quantitative estimates of the proportions of montmorillonite, chlorite/kaolinite and illite in each sample. Selected fragments from several of the coarse fractions (>62 microns) were also pul- verized and X-rayed using a Debye-Scherrer powder camera. Zn-filtered Moka radiation was used in some instances to reduce fluorescence of ferromanganese compounds in the samples. The 67 surface and 53 subsurface samples selected for geochemical analyses were air-dried and ground in a porcelain mortar to pass an 80- mesh sieve. Of each sample, 100 mg. were then treated for about 4 hours with 10 ml. of a solu- tion equivalent to IM-hydroxylamine hydroch- loride and 25 percent (V/V) acetic acid. The details and an evaluation of this procedure are given by Chester and Hughes (1967). This treatment dissolves most of the ferroman- ganese minerals, the carbonate minerals and extracts adsorbed trace metals, but does not af- fect detrital minerals (Chester and Hughes, 1967), other than detrital carbonates. After di- lution of the solutions resulting from the above treatment, suitable aliquots were analyzed for iron and manganese using atomic absorption (Beckman Model 1301 coupled to a DB-G Spectrophotometer). Standard solutions were prepared in a dilute HCl matrix and sample matrix efi'ects checked by standard additions. Duplicate and triplicate analyses of selected samples established that the analytical preci- sion was always within ±10 percent and fre- quently within ± 5 percent. Several samples were also analyzed for total iron and manganese. After fusing with LiBOa (Shapiro, 1967) the whole sediment was dis- solved in weak HCl and analyzed for iron and manganese using the same standards employed for the nondetrital extractions. Matrix eff'ects were present in the total iron and manganese analyses and the resulting values could only be considered semiquantitative. The concentra- tions obtained for extractable (nondetrital) and total manganese were similar, indicating that manganese is almost entirely associated with the nondetrital fraction. The total iron content, however, was three to four times higher than that found in the nondetrital ex- traction. This is in agreement with the findings of Chester and Hughes (1966, 1967, 1969) and suggests that iron is largely in the silicate or resistant oxide phases. Statistical The data of the sedimentary properties such as percent gravel, sand, silt, clay and mean grain size, standard deviation, skewness and kurtosis were computed by digital computer based on the results of the grain size analyses. The geochemical data for the surface samples were submitted to a series of linear multiple regression analyses using the computer. Miller (1956) and Krumbein (1959) have discussed the importance of similar analyses for the pur- pose of data "smoothing" and interpretation. Because of inequable sample spacing the geochemical Jata were divided into three geo- graphic groupings, the East Novaya Zemlya Trough (A^=15), the St. Anna Trough (A^ = 39) and the Voronin Trough (A^=13). Three-dimensional regression surfaces were developed for each of the three data groupings and for selected combinations of the groupings by using the expression Z = f(x,y)^', where x and y, the geographic coordinates of a sample location measured from an arbitrary origin, are the independent variables, and each geo- chemical attribute (z) is the dependent varia- ble. The independent variables are raised to higher and higher polynomials, with the coef- ficients of the polynomials being determined through standard macrix techniques on the digital computer using least squares analysis. A statistical analysis of variance was used to se- lect the polynomial which accounted for the largest significant reduction in the variability of the data (Goodell, 1967). For this study no polynomial higher than linear proved to be sig- nificant at the 95 percent confidence level. Results Color The color variations with depth in the 20 cores from the Edisto-Eastwind collection are given in figures 4-7. Although no two cores show exactly the same variations, there are marked similarities, especially in the upper 10 to 15 cm. With the exception of core E-32 which is greenish-gray throughout, every core is some shade of brown in the upper layers and grades sharply or gradually into gray or green lower layers. Several of the Edisto-Eastwind cores (table 7, e.g., E-8, 20 to 38.5 cm.) show gray-green layers which are mottled by black lumpy material similar to the substance de- scribed by Klenova (1948, cited in Strakhov, 1966) and identified as hydrotroilite (FeS n H.O). The generalized color sequence (table 1) given by Yermolayev (1948o,b), brown to dark brown to bright orange (brittle) to gray to brown (brittle) is best represented in cores E-8, E-12, E-18, E-25, E-26, E-31, E-34, and E-35. The rest have layers which can be iden- tified with one of Yermolayev's layers but the sequence is incomplete or out of order. The cores from the Northwind collection also show similar color variations with depth (Andrew, personal communication) and many display the generalized color sequence of Yer- molayev (table 1 and fig. 8, for typical se- quences). Texture The distribution of gravel, sand, silt and clay with depth in the eight cores from the No- vaya Zemlya Trough and two cores from the Svyataya Anna Trough is given in figures 5-7. Almost without exception the cores consist of silty clay (classification after Shepard, 1954) throughout. The exceptions are core E-28 which contains appreciable sand and gravel in the lower layer and core E-21 which has sandy layers. The 10 cores (fig. 4) not analyzed below the surface layer for grain size distribution like- wise consist of silty clay in the surface layers except for cores E-14 and E-15 which contain considerable sand and some gravel (app., table 8). There is no visible evidence table 7) of marked shifts in the proportions of sand, silt and clay below the surface layers of these cores. The statistical parameters (table 9) support the observation of little variability in the grain size distribution with depth in the cores. Al- most without exception the mean size of the sediments corresponds with very fine silt to clay on the Wentworth size scale and the sedi- ments are very poorly sorted, near-symmetri- cal to coarse-skewed and mesokurtic. The few departures from these characteristics are also reflected in the distribution of gravel, sand, silt and clay (figs. 5-7). The percentages of each size fraction show a marked increase in the amount of material finer than 1.0 micron below the surface layers. The quantity of this material increased from ca. 30 percent in the surface layers to ca. 40 percent on entering the subsurface gray-green layers and did not decrease again on entering secondary brown layers. Only where the per- 6 centage of sand-sized material increased signif- icantly over the mean for the whole core, as in core E-21, 22 to 36 cm. and 39 to 42 cm. and E-28, 20 to 28 cm., did the percentage of mate- rial finer than 1.0 micron decrease again in subsurface layers. Mineralogy The chief clay-sized minerals which were found in the samples examined by X-ray dif- fraction consisted of illite, chlorite, kaolinite, and an expandable component which is proba- bly montmorillonite. The percentages of each clay group (table 2) revealed moderate varia- bility with depth in the cores examined, with the greatest differences existing between the surface (0 to 3 cm.) and lower layers. The percentages of chlorite-kaolinite ranged from 21 to 32 percent in core E-26 and from 13 to 32 percent in core E-21, with the highest percentage occurring in the surface layers of both cores. The percentages of illite ranged from 33 to 50 percent in core E-26 and from 32 to 44 percent in core E-21 with the highest percentages in the lowest and surface layers respectively. In core E-26 the surface layer contained the second highest value of illite (48 percent). The percentages of montmorillonite ranged from 20 to 42 percent in core E-26 and from 24 to 53 percent in core E-21 with the lowest percentages occurring in the surface samples. The peak area ratios (table 2), chlorite- kaolinite /illite and montmorillonite/illite, range from 0.43 to 0.74 and 0.41 to 1.27 respec- tively in core E-26 and from 0.39 to 0.72 and 0.53 to 1.55 respectively in core E-21. In core E-26 the montmorillonite/illite ratio shows an increase with depth in the core in the upper brown layers followed by a sharp decrease on entering the upper gray layer. This ratio in- creases again in the secondary brown layer and adjacent layers in core E-26. The peak area ratios for core E-21 support the observation of an increasing montmorillonite/illite ratio with depth in the upper brown layers but reveal no increase in the montmorillonite/illite ratio in secondary brown layers. Microscopic examination of the coarse frac- tions from the upper layers of core E-26 re- vealed minor amounts of black crusty material in the layer 3 to 7 cm. from the surface and light brown earthy material in the layer 7 to 10 cm. from the surface. X-ray diffraction pat- terns (table 10) of these substances revealed a number of peaks which could not be attributed to any of the common detrital minerals and which did not seem to fit any of the published diffraction patterns of iron and manganese minerals. Many of the unidentified peaks were broad and diffuse, suggesting small particle size and/or poor crystallinity. Examination of the coarse fractions from other brown layers in core E-26 and in other cores revealed physically similar substances to those X-rayed but never in abundance except for core E-31 which contained abundant co- prolitic matter in a secondary brovsTi layer (20 to 23 cm.). X-ray study of this substance (table 11) proved it to be the iron phosphate, vivianite. Andrew (personal communication) also reported an occurrence of vivianite in a secondary brown layer in core N-77 (fig 3). Vertical distribution of nondetrital iron and manganese The vertical distribution of iron and manga- nese and sediment color in cores E-26 and N-148 is compared in figure 8. Manganese and iron are enriched in separate bands somewhat below the sediment-water interface in dark brown and yellowish-brown or reddish-brown layers respectively. Iron, and to some slight ex- tent manganese, are also concentrated in sub- surface brown layers but the enrichment here of both elements is not nearly so pronounced as in the near-surface layers. The Mn/Fe ratio (tables 12 and 13) is not constant but varies from 5.54 at 3 to 4 cm. to 0.03 at 8 to 9 cm. in core E-26 and from 1.40 at 5 to 6 cm. to 0.01 at 43.5 to 44.5 cm. in core N-148. The particu- larly high value for manganese (6.20 percent) at 3 to 4 cm. in core E-26 is notable because the value is higher than is usually observed, even in total sediment analysis. A secondary peak is observed on the shoulder of the major manganese peak in both cores. Regional distribution of nondetrital iron and manganese In the surface sediments of the Kara Sea the concentration of nondetrital iron varies be- tween 0.43 and 3.04 percent, the concentration of nondetrital manganese varies between 0.01 and 2.62 percent, and nondetrital Mn/Fe ratio varies between 0.02 and 2.15 (table 14). The mean values for iron, manganese and Mn/Fe ratio are highest in the East Novaya Zemlya Trough and lowest in the Voronin Trough, with the Svyataya Anna Trough having values more similar to the Voronin than to the East Novaya Zemlya Trough (table 3). All values show a high degree of variability within a trough but iron shows the least variability (tables). The data for the East Novaya Zemlya Trough are subdivided because the E-series samples represent the top centimeter of each sediment core and the N-series represent stra- tigraphic channel samples encompassing as much as 15 cm. of the top of a core. The signif- icance of the difference in these two sets of samples is related to the distribution of iron and manganese with depth in the cores (fig. 8). Surface samples which include more than the upper centimeter or two of sediment may in- clude iron and manganese from layers just below the surface which are greatly enriched in these elements. The data from Gorshkova (1957) for the southwestern Kara Sea (tables 3 and 14) which include several samples from the East Novaya Zemlya Trough and which represent samples from a wide range of water depths, tend to support the earlier suggestion that the reagents used in the present study extract only a small part of the total iron but almost all of the total manganese. The regression analyses of the geochemical data revealed no significant (at the 95 percent confidence level) surfaces higher than linear. Thus it is possible to express a trend as a com- pass direction with the dependent variable in- creasing in that direction. The content of nondetrital iron in surface sediments from the East Novaya Zemlya and Svyataya Anna Troughs increases towards the southeast (128° to 131°). In the Voronin Trough, nondetrital iron increases towards the south (192°). The residuals do not appear to have any geological significance (fig. 9). The similar trends observed for nondetrital iron in each trough are not observed for nonde- trital manganese (fig. 10). Each trough dis- plays a distinctly different trend direction. Manganese increases towards the coast of No- vaya Zemlya (287°) in the East Novaya Zem- lya Trough, towards the south (186°) in the Voronin Trough and towards the Central Kara Plateau (95°) in the St. Anna Trough. The re- siduals reveal a large area in the central St. Anna Trough which has a higher content of nondetrital manganese than the surface would predict. The positive residuals which appear in the East Novaya Zemlya Trough probably re- flect the sampling procedure used for the seven Northwind cores from this trough, i.e., strati- graphic channel sampling instead of the "spot" sampling used for all other cores, rather than any natural phenomenon. The nondetrital Mn/Fe ratio (fig. 11) in- creases northward (18°) and northeastward (45°) towards the Arctic Ocean in the Svy- ataya Anna and Voronin Troughs respectively, but increases westwards (288°) towards No- vaya Zemlya in the East Novaya Zemlya Trough. The residuals suggest that the Mn/Fe ratio is higher in the central parts of all three troughs than the linear surface would predict. No geological significance can be attached to the latter observation for the East Novaya Zemlya Trough because of the sampling dis- crepancy outlined previously. Discussion Although color is one of the most readily ob- served mass characteristics of a sediment it is also one of the more difficult to evaluate. The color of naturally moist sediments under simi- lar lighting conditions depends upon (1) the intrinsic color of detrital minerals of which each sediment is composed, (2) the size and packing of these minerals, (3) the amount and kind of organic matter, including skeletal ma- terial, and (4) the color and amount of any nondetrital constituents such as oxide coatings, cement and concretions (Weller, 1960; Krum- bein and Sloss, 1963). Any interpretation of sedimentary color must therefore consider the contribution of each of these factors to the total mass effect of color. 8 The detrital mineralogical observations of the present study do not reflect any significant changes in the clay mineralogy (table 2) or any readily apparent change in the detrital components of the coarse fractions across the upper layers of Kara Sea sediments. The ob- served downward increase in montmorillonite/ illite ratio across the upper brown layers and in the vicinity of the secondary brown layers in core E-26 would not contribute to the brown color of these layers because neither mont- morillonite nor illite are brown clay minerals (Keller, 1953). The possibility exists that a mixed layer clay incorporating an expandable minei-al and iron hydroxide (Rich, 1968) has formed in the Fe-rich layers but the evidence for this is weak. The effects of particle size and size distribu- tion can also be eliminated as responsible for the color variations in the upper layers of Kara Sea sediments because there are no marked textural changes across the upper lay- ers (figs. 5-7). The decrease in fine clay con- tent in the upper layers is probably related to authigenic cementation in this fraction by the high content of nondetrital ferromanganese oxides (fig. 8) and not to any real difference in the grain size distributions between surface layers and lower layers. Although particle packing increases with depth in sediments under natural compaction, in view of other fac- tors to be discussed subsequently, packing does not appear to be significant in determining color in the upper layers of Kara Sea sedi- ments. In the Kara Sea the nondetrital sedimentary constituents, the stabilities of which depend upon the sufficiency or insufficiency of oxygen, and low abundance of aquatic life, would ap- pear to exert the greatest influence on sedimen- tary color. Nondetrital iron and manganese compounds in varying proportions are the con- stituents of Kara Sea sediments which impart the brown color to the upper layers (Klenova, 1938; Brujevicz, 1938a,6; Trofimov, 1939; Klenova and Pakhomova, 1940 ; Yermolayev, 1948o,6; Gorshkova, 1957; figs. 5-7, this study). The sediment assumes a gray-green color typical of illite, chlorite and other clay minerals (Keller, 1953) when nondetrital iron and manganese are least abundant (fig. 8) and after mild acid leaching. That the brown color is nondetrital is also evidenced by the brown coatings on detrital mineral grains in the coarse fractions from brown layers. Any interpretation of the distribution of nondetrital iron and manganese in Kara Sea sediments must consider (1) the possible sources of iron and manganese, (2) the possi- bility of variability in the rates of influx and primary deposition of iron and manganese, and (3) the postdepositional mechanisms which could concentrate iron and manganese in some layers and not others in the absence of any variability in the rates of influx or primary de- position. The trend analyses of the distribution of nondetrital iron and manganese in surface sed- iments (figs. 9, 10 and 11) are an attempt to lo- cate the source(s) or point(s) of influx of these elements into the Kara Sea. Such an ap- plication of trend analyses assumes that nonde- trital elemental concentrations will increase to- wards the source(s) or point(s) of influx, when account is taken of dilution by detrital constituents. In the present study dilution ef- fects are minimized by sampling within a com- paratively narrow water depth range (200 to 600 meters), by small sample-to-sample varia- bility in grain size distribution (app., tables 10 and 11; Andrew, in preparation), and by ana- lyzing specifically for the nondetrital compo- nent of the total iron and manganese content. The observation of a regional increase in the concentration of nondetrital iron in surface sediments toward the Siberian mainland (southward) is consistent with a possible source for this element in the Siberian rivers. In order for the concentration of a nondetrital component to show a relative increase in the direction of a detrital source there must also be an increase in the absolute quantity of the non- detrital component to compensate for detrital dilution in the direction of the source. The spread of continental runoff across the Kara Sea from the river mouths to north of 80° (Milligan, 1969) also supports river discharge as the source of the nondetrital iron. On the basis of the trend surface analyses alone, it is not possible to determine the point(s) of influx of nondetrital manganese into the Kara Sea. Each deeper area reflects a different source, suggesting that factors other than distance from source influence the distri- bution of nondetrital manganese. These factors include the nature of water masses present in given areas as demonstrated by Klenova and Pakhomova (1940) and Kulikov (1961) and probably other redox potential determining factors, such as the content and type of organic matter. The observation of an increase in the nonde- trital Mn/Fe ratio in surface sediments avi^ay from the mouths of the Siberian rivers is con- sistent with deposition of most of the nondetri- tal iron nearer to the points of influx of iron into the Kara Sea. The positive residuals for nondetrital Mn/Fe ratio in the central areas of the Svyataya Anna and Voronin Troughs also support deposition of most of the nondetrital iron in shoaler water. These findings are in ac- cord with the suggestions of Murray and Irv- ing (1895) and more recently Skornyakova (1964) and Strakhov and Nesterova (1969) who attributed a real separation of iron and manganese in marine sediments to the greater chemical mobility of manganese compounds in near-shore sediments because of reduction by organic matter. Alternately Price (1967) and Krauskopf (1957) attributed increased Mn/Fe ratios on going from littoral to pelagic sedi- ments to the ease of precipitation of iron rela- tive to manganese when river water, charged with soluble divalent ions of these metals, en- ters the sea. Both processes lead to a seaward (pelagic) enrichment in manganese and thus increased Mn/Fe ratios in pelagic sediments. Although the Siberian rivers are the most logical source of nondetrital iron and manga- nese in Kara Sea sediments, submarine volcan- ism, which has been postulated (literature re- viewed by Bostrom, 1967) as a major source for nondetrital iron and manganese accumula- tions in sediments, may theoretically have con- tributed significant amounts of these elements to Kara Sea sediments. However, this possibil- ity is unlikely because there is no evidence (Saks, 1948; Saks and Strelkov, 1961) of re- cent submarine volcanic activity in the Kara Sea or the adjacent Barents and Laptev Seas and Arctic Ocean (Strakhov, 1966). Further- more it seems unlikely that the volcanic activ- ity associated with North Atlantic ridge sys- tems has contributed large amounts of iron and manganese to Kara Sea sediments and not to the sediments of adjacent seas (e.g., Nor- wegian Sea) which are closer to this obvious volcanic source. The observation of an expandable clay min- eral, which is probably montmorillonite, in Kara Sea sediments (table 2) is not prima facie evidence of a volcanic regime. Applying the criteria of Griffin and Goldberg (1963) for distinguishing volcanic from nonvolcanic montmorillonites in the marine environment to the Kara Sea, it can be established that mont- morillonite (1) is not the most abundant min- eral in the less than 2 micron fraction, (2) is not associated with the zeolite phillipsite and (3) is not associated with abundant volcanic shards or any of the other products of submar- ine volcanic effusions such as are reported from the Pacific Ocean by Bonatti and Nayudu (1965). Therefore, montmorillonite in Kara Sea sediments is almost certainly continentally derived. Variability in the rates of influx of iron and manganese into the Kara Sea, regardless of the source (s) or point (s) of influx, cannot satis- factorily account for the observed distribution of these elements with depth in cores (fig. 8). If this distribution were explained in terms of variability in the rate of influx of either of these elements, it would imply that they are geochemically much more dissimilar than is known to be the case (Rankama and Sahama, 1950). Although there is considerable evidence of preferential, or early, precipitation of iron in soil-forming processes, preferential dissolu- tion and transport of iron unaccompanied by manganese rests on extremely flimsy evidence (Krauskopf, 1957). Thus we would expect the Mn/Fe ratio in fluvial waters to remain rela- tively constant even if the absolute amounts of each element changed. Eustatic control of the deposition of ferro- manganese compounds has been suggested (Goodell, personal communication) to account for cyclic brown banding in delta and near- shore sediments. Under this model rates of de- trital sedimentation at low stands of sea level are fast (relatively) in near-shore areas (Huang and Goodell, in press) and chemical elements associated with the finest suspended matter are highly diluted and concentrate only in pelagic areas. At high stands of the sea, rates of sedimentation are comparatively slower in former, i.e., relict, near-shore areas permitting such elements as iron and manga- nese to concentrate in these areas. During sub- 10 sequent lower stands the brown layers formed during high stands are buried under iron-and manganese-deficient sediments and presumably preserved as brown interlayers. Furthermore, because iron is chemically more stable than manganese in near-shore areas, or accumulates more rapidly than manganese in these areas, it is possible that sediments deposited at low stands of sea level are more iron-rich than those deposited in the same area at higher stands of sea level. Eustatic control of the deposition of nonde- trital elements in the Kara Sea is difficult to evaluate at present because of the conflicting evidence of sea level fluctuations in the Kara Sea region during the Quaternary (Lazukov, 1964) and because of the few reliable estimates of rates of sedimentation in the Kara Sea which have been published. That sea level is a signifi- cant factor is doubtful because the variability in the Mn/Fe ratio in surface sediments (table 14) is relatively low compared with the varia- bility of this ratio with depth in typical cores (tables 12 and 13). If it has been the history of regional variability of this ratio which pro- duced its stratigraphic variability, then the or- ders of magnitude of both variabilities (re- gional and stratigraphic) should be similar. Furthermore, development of brown surface layers and interlayers does not seem to have been limited to certain water depth ranges and in fact extends to the greatest depths of the Arctic Ocean (Strakhov, 1966; Belov and Lap- ina, 1959). Considerable evidence has been gathered (Murray and Irvine, 1895; Brujevicz, 1938a, b; Mortimer, 1942; Bezrukov, 1960; Manheim, 1965; Lynn and Bonatti, 1965; Strakhov, 1966; Anikouchine, 1967; Price, 1967; Presley, Brooks, and Kaplan, 1967 ; Li, Bischoff, and Mathieu, 1969) which suggests, and frequently supports, postdepositional redistribution of manganese where oxidizing upper layers are underlain by reducing layers such as in the Kara Sea (fig. 2). This model proposes that manganese, incorporated into accumulating sediments as the oxide, is remobilized after burial by local reducing conditions and diff"uses upward in response to the concentration gra- dient produced by reprecipitation of manga- nese in upper oxidized strata. The factors which appear most important for the produc- tion of reducing environments in sediments are the amount and type of decomposable organic matter deposited contemporaneously with the sediment and the rate of accumulation of the sediment (Lynn and Bonatti, 1965). Dissolved oxygen in bottom water, and that which dif- fuses into the sediment, is probably responsible for the reprecipitation of manganese in upper strata although there is some evidence (Gabe, Troshanov, and Sherman, 1965; Ehrlich, 1966) that bacteria precipitate reduced manganese ions from interstitial water. The upward enrichment of manganese in typical Kara Sea cores is consistent with the migration model outlined above. The compara- tively fast rates of sedimentation (4 to 6 cm. per 1,000 years, Kulikov, 1961) apparently favor burial of enough organic matter to prod- uce reducing conditions below the upper oxidiz- ing layers. Reducing conditions in buried lay- ers of Kara Sea sediments are supported by (1) negative redox potentials (Eh) below the upper few centimeters (Trofimov, 1939), (2) Fe'*/Fe^* ratios ranging from 0.1 to 2 in gray-green layers as compared with 2 to 20 (and as much as 56) in brown layers (Yermo- layev, 1948a,6), and (3) the presence of hydro- troilite in gray-green layers (Klenova, 1948, cited in Strakhov, 1966). The upward enrichment of iron and its sepa- ration from manganese (fig. 8) has apparently not been observed in marine sediments before but is also consistent with the migration model when consideration is given to the greater sta- bility of iron oxides under redox conditions fa- voring solubilization of manganese oxide and the greater ease of oxidation of reduced iron compared with reduced manganese (Kraus- kopf, 1957; Hem, 1963). Assuming that man- ganese and iron have been released into the in- terstitial water of gray-green layers and that a gradient in oxidation potential exists between the interface, iron should precipitate first from an upward diffusing solution containing both iron and manganese ions even if only inorganic processes are operating. The models which require reduced rates of sedimentation for formation of brown layers (Arrhenius, 1963; Goodell, personal communi- cation) are not inconsistent with postdeposi- tional i-edistribution of iron and manganese. In fact, such a rate reduction in the accumulation 11 of detrital material may favor development of the elemental distributions such as observed in the present study. Under the influence of a con- stant, comparatively rapid (4 to 6 cm./lO^ years), rate of sedimentation, the interface be- tween oxidizing and reducing conditions vv^ould be continuously destroyed and new interfaces constructed at progressively higher strati- graphic levels. Presuming that dissolution and diffusion processes in clayey marine sediments are extremely slow, no significant enrichment of iron or manganese in the upper oxidizing layers could take place under conditions of con- stant rapid sedimentation. On the other hand a period of reduced sedimentation would permit diffusion processes to concentrate the more mo- bile elements in the upper layers before burial and reduction can remobilize them. In addition, the reduced deposition of detrital matter would permit a relative increase in the primary accu- mulation in surface layers of nondetrital sub- stances such as ferromanganese colloids and their associated "scavenged" (adsorbed) trace metals. Thus the models proposing primary processes for the development of brown layers and those proposing postdepositional processes need not be mutually exclusive. It is doubtful that only inorganic processes are important in the postdepositional redistri- bution of iron and manganese. The activities of bacteria and other microorganisms are thought to play a main role in the decomposition of or- ganic matter and thus production of reducing conditions in sediments (ZoBell, 1946). The ex- periments of Yermolayev (1948a,6) involving the inversion of a typical Kara Sea core clearly demonstrate the role of bacteria in the mobili- zation of iron and manganese in sediments iso- lated from gaseous exchange with overlying water. The work of Perfilev et al. (1965) and Ehrlich (1966) also supports the importance of bacteria in the production of reducing condi- tions in sediments, thus solubilizing the iron and manganese, and provides some evidence as to the role of bacteria in the oxidation or pre- cipitation of iron and manganese when the sed- iments are oxidized. The work of Gabe, Tro- shanov, and Sherman (1965) is particularly pertinent to the present study because they ob- served color sequences and iron-manganese dis- tributions in a core from Lake Valk-Yarvi (table 4) identical to those observed in the upper layers of cores E-26 and N-148 from the Kara Sea. In addition, they found abundant development of microbes, Metallogeniw7t and Siderococcus, known to derive energy from the oxidation of reduced iron and manganese, in the respective sediment layers enriched in these elements. Whether similar microbes are responsible for the oxidation of iron and man- ganese in Kara Sea sediments remains to be es- tabli.?hed. The existence of secondary (buried) layers, weakly enriched in iron and manganese, im- plies that not all the nondetrital iron and man- ganese have been released into interstitial water below the oxidizing zone and migrated upward. This may be due to a nonuniform dis- tribution of organic matter as has been sug- gested by Oppenheimer (1960) to account for color banding in Texas marine bay sediments. Another possibility is that the iron and manga- nese in the secondary brown layers have been irreversibly oxidized, as Yermolayev (1948a,&) has proposed, but are still readily reduced by the hydroxylamine hydrochloride-acetic ac'd treatment. The occurrence of the iron phos- phate, vivianite, as coprolitic concretions in the secondary brown layers of cores E-31 and N-77 is almost certainly authigenic and may imply higher biological productivity, possibly in response to an influx of warmer waters as proposed by Yermolayev (1948a,6), at the time these layers were deposited. Conclusions This textural, mineralogical and geochemi- cal study of Kara Sea sediments allows the fol- lowing conclusions and generalities to be drawn regarding the significance of color vari- ations in the upper layers : 1. The color sequences observed in typical Kara Sea cores are not related to stratigraphic variability in texture or detrital mineralogy. 2. Nondetrital iron and manganese com- pounds are the constituents of Kara Sea sedi- ments which impart the brown color to the upper layers. 12 3. The source(s) or point(s) of influx into the Kara Sea of iron and manganese is (are) probably the Siberian rivers which enter the sea from the south. 4. Factors other than distance from source (s) or point (s) of influx apparently con- trol the distribution of nondetrital manganese in the surface sediments of the Kara Sea. 5. Nondetrital manganese may be trans- ported farther from its point(s) of influx into the Kara Sea than nondetrital iron, or be chemically more stable in the deeper areas of the Kara Sea. 6. The distribution of nondetrital iron and manganese, and thus color, with depth in Kara Sea cores appears to be controlled by postde- positional processes, including dissolution, mi- gration, and subsequent differential oxidation of reduced iron and manganese ions, rather than by primary depositional processes. Acknowledgement This study was partially supported from June 1969 to June 1970 by a U.S. Coast Guard cooperative study program. References Andrew J. A., in preparation, A sedimentolo^cal study of the Kara Sea, north of 76° North: Ph. D. disserta- tion, University of Wisconsin. Andrew, J. A., and Kravitz, J. 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V., 1960, The geology of the USSR, a short outline: Pergamon Press, New York, 170 pp. Nesterova, I. L., 1960, Chemical composition of the sus- pended and dissolved loads of the Ob River: Geo- chemistry, No. 4, pp. 424-431. Nordenskjold, 0., and Mecking, L., 1928, The geogra- phy of the Polar regions: Am. Geogr. Soc, Spec. Pub. No. 8, New York. Oppenheimer, C. H., 1960, Bacterial activity in sedi- ments of shallow marine bays: Geochem. cosmochim. Acta, V. 19, pp. 244-260. Perfil'ev, B. V., Gabe, D. R., Gal'perina, A. M., Rabi- novich V. A., Sapotnitskii, A. A., Sherman, E. E., and Troshanov, E. P., 1965, Applied capillary microscopy — The role of microorganisms in the formation of iron-manganese deposits (transl. by F. L. Sinclair) : Concultants Bureau, New York, 122 pp. Presley, B. J., Brooks, R. R., and Kaplan, I. R., 1967, Manganese and related elements in the interstitial water of marine sediments: Science, v. 158, pp. 906-909. Price, N. B., 1967, Some geochemical observations on the manganese-iron oxide nodules from different depth environments: Mar. Geol., v. 5, pp. 511-538. Rabkin, M. I., and Ravich, M. G., 1961, The Pre- cambrian of the Soviet Arctic, pp. 18-30 in Raasch, G. 0., Editor, Geology of the Arctic, v. 1 : University of Toronto Press. Rankama, K., and Sahama, Th. G., 1950, Geochemistry: The University of Chicago Press, Chicago and London, 912 pp. Rich, C. I., 1968, Hydroxy interlayers in expansible layer silicates: Clays and Clay Minerals, v. 16, pp. 15-30. Sachs, V. N., 1948, Quaternary Period in the Soviet Arctic [in Russian] : Trudy ark. nauchno-issled Inst, V. 201, pp. 12-17, 62-74 (Transl. No. 338, USN Oceanogr. Off.). Sachs, V. N., and Strelkov, S. A., 1961, Mesozoic and Cenozoic of the Soviet Arctic, pp. 48-67 in Raasch, G. O., Editor Geology of the Arctic, v. 1: University of Toronto Press. Shapiro, L., 1967, Rapid analysis of rocks and minerals by a single-solution method: Prof. Pap., U.S. Geol. Surv., 575-B, pp. 187-191. 14 Shepard, F. P., 1954, Nomenclature based on sand-silt- clay ratios: J. Sed. Patrol., v. 24, pp. 151-158. Skornykova, I. S., 1964, Dispersed iron and manganese in Pacific Ocean sediments : Int. Geol. Rev., v. 7, pp. 2161-2174. Strakhov, N. M., 1966, Types of manganese accumula- tion in present-day basins, their significance in under- standing of mangane.^e mineralizaticn: Int. Geol. Rev., V. 8, pp. 1172-1196. Strakhov, N. M., and Nesterova, I. L., 1969, Effects of volcanism on the geochemistry of marine deposits in the Sea of Okhotsk: Geocheni. Int., v. 5, pp. 644-666. Trofimov, A. V., 1939, Oxidizing activity and pH of brown sediments of the Barents Sea : Compt. rend. Acad. Sci., URSS, v. 23, pp. 925-928. Weller, J. M., 1960, Stratigraphic principles and prac- tice: Harper and Bros., New York, 725 pp. Yermolayev, M. M., 1948a, Lithogenesis of plastic clay sediments in seas [in Russian] : Izv. Akad. Nauk SSSR Ser. Geol., No. 1, pp. 121-138 (Transl. No. 355, USN Oceanogr. Off.). Yermolayev, M. M., 19486, The problem of historical hydrology of seas and oceans [in Russian] : Vop. Geogr. Klimatol. Gidrol., v. ,7pp. 27-36 (Transl. No. 346, USN Oceanogr. Off.). Zenkevitch, L. A., 1963, Biology of the seas of the USSR: Interscience Publishers, New York, 955 pp. Zenkovitch, V. P., Leontiev, 0. K., and Nevessky, E. N., 1960, Influence of the eustatic post-glacial transgres- sion upon the development of the coastal zone of the USSR seas: 21st Int. Geol. Congr. Proc, pt. 10, pp. 65-72. ZoBell, C. E., 1946, Studies of redox potential of ma- rine sediments: Bull. Am. Ass. Petrol. Geol., v. 30, pp. 477-513. 15 «0* O' CO ZEMLYA FRANTSA lOSIFA 75' -1— 90° —I— Circulation Pattern Surface Currents Johnson and Milligan (1967) Zenkevitch (1963) Bottom Currents Zenkevitch (1963) — ~ ' ■ Figure I. Physiography and circulation pattern of the Kara Sea. 16 Redox Potential (mV) pH Figure 2. Redox potential and pH in two KNIPOVICH cores from the Kara Sea. 17 Figure 3. Station locations and bathymetry. 18 12 20 o 24 28 32 36 40 44 48 52 56 14 7T^ [^ CORE N U MB E R(E-SE R I E S) 15 18 20 32 99 94 99 96 ir IPT' vi;.i I'l'. I Jh'.'i i Ei\iii ^ 1 i ■:•;•:■: $:;:^^ C3 MODERATE OLIVE BROWN ^ LIGHT OLIVE BROWN m MODERATE YELLOWISH BROWN ^ DARK YELLOWISH BROWN cm GRAYISH BROWN E23 BROWNISH GRAY OLIVE GRAY DARK GREENISH GRAY Figure 4. Color variations with depth in 10 cores from the northern Kara Sea. 19 2 ,2 O UJ cc o 16 20 24 28 32 36 40 44 48 CORE E-8 0 10 20 30 40 50 r.] ? ' ' S — £- * oo % SAND % SILT 7oCLAY SAMPLING INTERVAL [\/\l GRADATIONAL BOUNDARY MODERATE OLIVE BROWN CORE E-ll 0 10 20 30 40 50 60 I I I I 1 I ir -1 f a o /\ o o I / a o a e DARK YELLOWISH BROWN ^^H^ MODERATE YELLOWISH BROWN GRAYISH BROWN OLIVE GRAY DARK GREENISH GRAY Figure 5. Color variations and distribution of gravel, sand, silt and clay with depth in cores from stations E-8 and E^ll (Svyataya Anna Trough). 20 tr o o o I- < - in CVJ o . cu o . -«— — « — — <- O K OD > 3 T) j- Z » o * i z (r m H >< ml J2 S » I " E o a: (o (Tl V « < - Si- I cc en > to z B . * o in o B eg o I. a (WO) 3 a 0 0 N I H i d 3 a 21 ? UJ Q cc •* o o o < o to o (0 UJ o o UJ 8 o o O iUJ.j.WWIW^H^^f^^W^W^^^ e &S (WD) 3800 Nl Hid3 22 PERCENT 2,0 4.0 6.0 COLOR PERCENT 0.0 2.0 4.0 6.0 1 — I — I — I — r CORE E-26 COLOR 40 44 48 .;::::::--'-Mn J I I I I L Dark Yellowish Brown Grayish Brown Modarote Yellowish Brown Olive Gray Moderate Yellowish Brown Olive Gro y Moderate Yellowish Brown Olive Groy Moderate Yellowish Brown Olive Gray - I J L J L J. ■, 1 . 1 1 1 1 1 CORE N-148 Moderote ■■>Mn Brown **• Dark , Grayish ''^- Brown ]^^»Fe Moderate Reddish Brown Grayish Brown Gray Grayish Brown Ye I. Br. Grayish Brown Dark Gray Figure 8. Distribution of nondetrital iron and manganese and color in core E-26 andN-148. 23 zemlyJ frantsa KARA SEA % NON-DETRITAL Fe Q Positive Residual Figure 9. Percent nondetrital iron in surface sediments (linear trend surface). 24 60 ZEMLYA FRANTSA ^4, -rosjFA KARA SEA %NON-DETRITAL Mn Q Positive Residual Figure 10. Percent nondetrital manganese in surface sediments (linear trend surface). 25 Figure 11. Nondetrital Mn/Fe Ratio in surface sediments Ginear trend surface). 26 Ta21Z 1. — Pnfle g/ (after '. lg.5-210 2C1-21 21—54 TJpp^ zone of viscoos C3d- fiaedamc Er: — Upper r Rrr liqnL Briiilp, bxri la lb ns Ob TA31Z '•=7-J 3.^ f K«v'fci<^ after Bixajfe {19fS) Mn F-: CL-.3 32 4S _ 3-7 23 42 -l-I 7-10 25 33 42 10-lS 22 45 ---- ia-16 27 42 16-19 22 ^^ 19-22 21 41 :• 3&-42 22 5 Ul flL99 'X-Seri^ rrlv. N-=r>. lya Trough r:-iv 23 out 9.2S 6L^ jMFraL — "'>'" is ^e 33:=r&^ :^ s«rr:rIJes iaeaaoair i— Bad 2f Table 4. — Distribution of manganese and iron oxides in secondary microzonal profile of mud from Lake Valk-Yarvi (after Gabe et a,l., 1965) Table 6. — Station positions and water depths for Edisto-Eastwind (1967) ; sediment samples Horizon Percent Remarks Mn,0, r'e,o, Oxidizing horizon , 0.93 1.90 Black-brown G.03 3.G0 Abundant develop- microzone. ment of Metallo- genium. Orange microzone 0.46 8.90 Abundant develop- ment of Sidero- coccus. Reducing horizon 0.33 2.71 Table 5. — Station positions and water depths for Northwind (1965) ; sediment samples station Latitude Longitude Depth No. (N) (E) (meters) 61 77-31.8 76-42.0 280 77 78-03.4 74-38.0 362 101 80-36.0 87-39.0 310 102 81-04.0 87-32.0 340 107 81-30.5 87-39.0 420 108 81-30.5 84-54.0 410 109 81-32.7 82-18.0 316 110 81-34.8 79-52.0 203 112 81-37.0 75-20.0 421 113 81-36.0 73-00.0 640 114 81-42.3 70-46.0 631 115 81-35.5 67-32.0 567 116 81-02.2 67-07.8 475 117 80-58.1 69-34.0 566 118 81-03.0 72-00.0 588 122 81-08.0 82-05.0 268 123 81-07.0 83-58.0 298 124 80-35.8 83-59.0 315 125 80-00.5 84-01.0 205 126 79-35.5 84-02.0 217 131 80-41.1 82-13.0 202 134 80-36.8 74-32.0 243 135 80-39.9 71-43.0 593 136 80-42.9 69-10.0 549 137 80-45.1 66-49.0 498 139 80-00.0 64-15.0 228 141 80-00.0 66-54.5 520 142 80-00.0 69-47.0 564 143 80-00.0 72-11.0 538 144 80-00.0 74-36.0 215 147 79-34.9 72-00.0 521 148 79-35.0 69-27.0 532 149 79-35.2 66-57.0 526 151 79-06.2 64-06.0 260 152 79-05.5 69-02.0 525 153 79-05.0 74-09.0 366 154 78-37.3 71-41.0 485 155 78-12.6 69-00.0 443 156 78-50.7 66-39.0 374 157 78-33.0 63-38.0 338 Sample No. Latitude (N) Longitude (E) Depth ( meters) 8 77-27.6 75-28.0 227 11 80-25.0 72-19.0 556 12 81-25.2 77-55.5 202 14 80-15.7 74-04.4 220 15 79-15.2 74-48.0 252 18 78-58.8 75-04.0 273 20 78-34.5 74-08.5 352 21 72-25.7 56-30.5 300 22 72-09.0 57-52.4 245 25 73-02.1 59-27.0 364 26 73-17.0 58-00.0 291 28 74-06.0 59-51.0 260 29 74-57.0 61-52.0 354 30 75-30.5 65-46.0 326 31 75-17.2 66-30.0 236 32 77-37.0 69-23.0 440 33 78-03.0 68-10.0 430 34 78-29.0 66-55.0 390 35 78-55.0 65-36.0 361 36 79-19.0 64-16.0 311 28 Table 7. — Core descriptions (ESeries) Core No. Interval (cm.) Colo Name Description 08 11 12 14 15 18 20 0-4.0 4.0-19.0 5Y4/1 . 19.0-20.0 10YR4/2 20.0-38.5 5GY4/1 0-9.5 9.5-47.5 0-3.5 3.5-4.5 4.5-6.5 6.5-18.5 18.5-19.5 19.5-47.0 0-4.0 4.0-9.0 0-4.0 4.0-26.5 5Y4/4, 10YR4/2, Clay, sandy, 10YR5/4. silty. do do do 10YR5/4 Clay, silty, foraminiferal. 5YR4/1 Clay, silty 5Y4/4, 10YR4/2, 10YR5/4. 5GY4/1 Clay, sandy, silty. Clay, silty, sandy. do . 5GY4/1 do 5Y4/4 Clay, sandy, silty. 5YR4/1 Clay, silty 0-5.0 5Y4/4 Clay, silty, sandy. 5.0-9.0 5Y5/6 Clay, sandy, silty. 9.0-11.5 10YR5/4 do 11.5-28.0 5GY4/1 do 0-4.5 5Y4/4. 10YR4/2, 10YR5/4. do 4.5-56.0 5GY4/1 do 5Y4/4 do 5GY4/1 Clay, silty Sharp color change with unit below; three slight color changes within unit as indi- cated. Mottled appearance with lower sec- tion brittle. Homogeneous throughout; worm tubes, little mottling. Sharp color change with unit above and be- low; mottled appearance; brittle. Homogeneous except for slight color grada- tion at top and mottling by black carbona- ceous matter at bottom. Sharp color change with unit below; spicules and agglutinated tests evident as are worm tubes. Homogeneous over entire unit; carbonaceous matter in lumps produce black streaks when smeared. Sharp color change with unit below; worm tubes; three color changes within this unit as indicated ; mottled appearance with 4.5-6.5 cm section having brittle texture. Homogeneous except for slight color change; some carbonaceous matter. Sharp color change with units above and below; mottled appearance as in 0-6.5 cm section. Mottled with black carbonaceous matter more so towards bottom. Sharp color change with unit below; color grades from 5Y4/4 to 5Y5/6 within unit; mottled appearance with lower section brittle. Homogeneous over entire unit; boundary with unit above at angle probably due to corer hitting at angle. Moderate color change with unit below; quite loosely compact (soupy). Slight color change with unit below; be- comes more compact with depth ; black mottling with carbonaceous matter. Hard, compact, mottled, brittle; sharp color change with unit below. Homogeneous throughout unit; no carbona- ceous mottling. Sharp color change with unit below; three color changes in this unit as indicated. Homogeneous throughout unit; worm tubes; carbonaceous mottling which seems to be associated with decomposing worm tubes; earthy odor. Sharp color change with unit below; color grades from 5Y4/4 to 5Y5/6; mottled ap- pearance; brittle. Homogeneous over entire unit; mottled with carbonaceous matter. 29 Table 7. — Core descriptions (E-Series) — Continued Core No. Interval (cm.) Color Name Description 21 22 25 26 28 29 0-9.5 9.5-17.0 17.0-19.5 19.5-35.5 35.5-38.5 38.5-49.5 0-3.0 3.0-59.0 0-7.5 7.5-9.5 9.5-12.0 12.0-15.0 15.0-20.5 20.5-53.0 0-12.5 12.5-18.5 18.5-21.0 21.0-23.0 23.0-28.5 28.5-32.5 32.5-37.5 37.5-47.0 0-19.5 19.5-25.5 0-17.0 17.0-18.5 18.5-22.0 22.0-23.5 23.5-28.5 10YR4/2, 10YR5/4. 5Y5/2 5Y4/4, 10YR4/2. 5Y5/2 5Y4-4, 10YR4/2. 5Y4/1 5Y4/4 5G4/1 5YR3/2, 5YR2/2, 10YR4/2. 5Y5/2, 5Y4/1 .._ 5Y5/2 10YR4/2 -_ 5Y5/2 10YR4/2, 5YR3/2, 10YR5/4. 5Y4/1 ____ 10YR5/4 -. 5Y4/1 10YR5/4 .. 5Y4/1 10YR5/4 -_ 5Y4/1 10YR4/2 .. 5Y4/1 10YR4/2, 5YR3/2. 5YR4/1 ._ 5YR4/2 __ 5YR4/1 5YR4/2 do Sharp color change with unit below ; mottled. do Distinct from units above and below but mottled 10YR4/2 to 5YR4/4; may be dis- turbed. do Moderate color change with units above and below. Clay, silty, Homogeneous over most of unit with sections sandy. 22-23 cm and 29-30 cm somewhat browner. Possibility of being disturbed. Sandy layer 32.5-33.5 cm. Clay, silty Sharp color change with units above and below; brittle. Clay, silty, Homogeneous over entire unit except for sandy. sandy layer at 41-42 cm. Clay, silty Sharp color change with unit below. Not as brown as surface layers in other cores. do Homogeneous over entire unit ; mottled with black carbonaceous matter throughout. do Sharp color change with unit below; three color changes in this unit as indicated; lower layers brittle. do Sharp color change with units above and be- low; homogeneous. do Sharp color change with units above and below ; moderately brittle. do Sharp color change with units above and below; homogeneous. do Sharp color change with units above and below; very brittle. do Homogeneous over entire unit. do Sharp color change with unit below; three color changes within unit; lower layer moderately brittle. do Homogeneous over entire unit except for small brown fragment at 14-15 cm. do Sharp color change with units above and below ; moderately brittle. do Homogeneous over entire unit. do Moderate color change with units above and below ; brittle lower layer. do Homogeneous over entire unit. do Moderate color change with units above and below. Moderately brittle. do Homogeneous over entire unit. Clay, silty. Slight color variation to 5YR4/4 at about sandy. 8 cm. Clay, silty, Sharp color change and textural change with sandy, gravel. unit above. Quite dry and brittle. Clay, silty. Moderate color change with unit below, sandy. Mottled with 5YR3/2. do Homogeneous over entire unit. Clay, silty Sharp color change with units above and below; moderately brittle. do Homogeneous over entire unit. do Sharp color change with units above and below; moderately brittle. 30 Table 7. — Core descriptions (E-Series) — Continued Core Interval No. (cm.) Color Name Description 28.5-30.0 N6 do ..-. Sharp color change with units above and below; very soft and soupy. 30.0-35.0 5YR4/4 do ..^ Mottled with light yellow ; somewhat brittle. 35.0-37.0 5YR4/1 , . do Moderate color change with units above and below; homogeneous over entire unit. 37.0-40.0 5YR4/2 do Quite brittle ; homogeneous except for sandy layer at 37.0-37.5 cm. 30 0-12.0 10YR4/2, 5YR3/2. do .. Moderate color change with unit below; color change at about 7 cm. as indicated. 12.0-28.5 5YR4/1. 5YR4/2. do .... Mottled over entire unit as indicated; ap- parently homogeneous otherwise. 28.5-32.5 5YR4/1 do .. Moderate color change with units above and below; homogeneous. 32.5-34.0 5YR4/4 do Homogeneous ; somewhat brittle. 34.0-36.5 N6 do .... Sharp color change with units above and be- low; homogeneous. 36.5-39.0 5YR4/4 do ..__ Sharp boundary with unit above; brittle. 31 0-12.5 5Y4/4, 10YR4/2, 10YR5/4. do .... Sharp color change with unit below; three color changes within unit as indicated ; brit- tle lower layer. 12.5-20.0 5YR4/1 do .... Homogeneous except for slight mottling at 16-17 cm. and 18-19 cm. 20.0-22.0 5YR4/6 do .... Sharp color change with units below and above; moderately brittle. 22.0-28.0 5YR4/1 do Homogeneous over entire unit. 28.0-47.0 5YR4/1 do .... Homogeneous except for mottling between 35-38 cm. 32 0-15.0 5GY4/1 do .... Mottled 10YR4/2 especially around worm tubes. Considerable turnover by bacteria since storage. 33 0-2.5 5YR3/4 do .... Sharp color change with unit below ; rather liquid. 2.5-48.0 5Y4/1 do .... Homogeneous except mottling with black carbonaceous matter in lower and middle of unit. 34 0-4.5 5YR3 4, 5YR3'2, do .... Sharp color change with unit below ; three 4.5-7.0 10R3/6. color changes in this unit as in E-15, E-18, 7.0-11.0 and E-12 but lithologies similar. 7.0-11.0 cm. somewhat brittle. 11.0-36.5 5YR4/1 do .... Slight color change at 17-24 cm. to mottled gray and brown (10YR4/2). 35 0-16.0 5Y4/4, 10YR4/2, do .... Sharp color change with unit below; three 16.0-20.0 10YR5/4. slight color changes within unit as indi- 20.0-25.0 cated; lithologies appear similar; 20-25 cm. brittle; worm tubes. 25.0-46.0 5YR7/2 do .. Lower centimeters darkened suggesting that texturally coarser sediment penetrated. 36 0-15.0 5YR3/4 do .... Slight color change with unit below. 15.0-22.0 5YR4/4 do .... Sharp color change with unit below. 22.0-28.0 5YR4/1 Do. 31 Table 8. — Gravel, sand, silt, and clay percentages Table 8. — Continued Core No. Interval (cm.) Gravel Sand Silt Clay E-8 0-1 8.60 50.00 41.30 E-8 2-5 8.02 38.80 53.18 E-8 5-7 10.20 53.30 36.50 E-8 11-13 15.60 43.10 41.30 E-8 _ 15-17 16.70 42.80 40.50 E-8 . 20-22 18.80 39.60 41.60 E-8 _ 25-27 15.00 41.90 43.10 E-8 . 31-33 11.20 45.50 43.20 E-8 . 39-42 6.10 45.60 48.40 E-11 0-2 2.70 45.90 51.40 E-11 2-7 2.00 40.53 57.47 E-11 6-8 1.80 41.50 56.60 E-11 _ 11-13 2.40 36.60 61.00 E-11 _ 15-17 3.60 38.60 57.80 E-11 . 21-23 2.90 37.20 60.00 E-11 . 25-27 6.90 34.40 58.60 E-11 _ 31-32 7.20 36.20 56.60 E-11 _ 35-37 5.30 34.70 59.90 E-11 41.43 11.30 41.30 47.40 E-12 0-5 3.32 49.52 47.16 E-14 0^ 3.62 35.03 33.68 27.67 E-15 0-4 33.47 25.56 40.97 E-18 0-4 4.21 39.11 56.68 E-20 0-4 8.59 40.95 50.46 E-21 0-3 7.74 36.22 56.04 E-21 3-7 5.39 33.45 61.16 E-21 . 14-17 6.57 25.82 67.61 E-21 17-20 5.77 27.26 66.97 E-21 _ 20-23 5.49 27.16 67.35 E-21 _ 32-36 18.01 25.91 56.08 E-21 . 36-39 11.40 24.35 64.25 E-21 _ 39-42 22.02 23.07 54.91 E-22 0-2 4.91 37.72 57.37 E-22 _ 10-12 4.83 30.38 64.79 E-22 . 20-22 4.82 29.88 65.30 E-22 _ 31-33 6.63 27.38 66.12 E-22 _ - 40^2 4.63 29.41 65.96 E-22 _ 51-53 9.91 27.62 62.47 E-25 0-3 3.41 30.84 65.75 E-25 3-10 1.92 25.68 72.35 E-25 _ 10-13 2.28 23.33 74.39 E-25 _ 13-15 1.61 21.88 76.45 E-25 . 15-19 1.42 26.60 72.08 E-25 19-22 1.82 24.17 74.01 E-25 „ 22-30 2.03 23.79 74.18 E-25 . 30-33 2.56 22.19 75.25 E-25 33-40 1.90 23.70 74.40 E-25 _ 40-43 2.23 20.31 72.46 E-25 . 43-50 1.93 23.18 74.89 E-25 _ 50-54 2.18 21.92 75.90 E-26 0-3 1.41 7.45 29.74 61.40 E-26 3-7 5.46 32.13 62.41 E-26 7-10 5.40 29.08 65.52 E-26 ._ 10-13 7.30 29.80 62.90 E-26 ._ 13-16 1.80 8.58 24.82 64.80 E-26 .. 16-19 7.27 25.46 67.27 E-26 .. 19-22 8.82 23.96 67.22 E-26 .- 22-25 7.46 24.47 68.07 Core No. Interval (cm.) Gravel Sand Silt Clay E-26 25-28 E-26 28-31 E-26 31-34 E-26 34-37 E-26 37-40 E-26 40-43 E-26 43-47 E-28 _ - 0-3 E-28 10-13 E-28 20-23 E-28 23-26 E-29 0-3 E-29 7.5-10.5 E-29 19-22 E-29 29-32 E-30 0-3 E-30 7.5-11.5 E-30 20-23 E-30 30-33 E-30 36.5-40 E-31 0-3 E-31 8.5-11.5 E-31 20-23 E-31 30-33 E-31 40-43 E-32 0-5 E-33 0-4 E-34 0-5 E-35 0-5 E-36 0-5 4.48 3.67 7.50 9.82 7.00 8.24 8.29 11.14 14.47 6.83 5.68 19.26 16.92 4.90 2.22 1.46 1.17 3.89 1.61 0.75 0.74 1.67 4.14 2.64 3.40 3.00 3.29 4.17 8.19 2.32 1.93 5.03 24.12 23.30 22.79 24.60 23.65 24.60 27.84 26.17 23.82 33.69 40.99 30.64 28.61 24.32 20.94 30.78 25.34 23.29 20.05 23.87 38.00 27.04 24.09 24.49 22.30 45.96 41.07 41.66 23.18 44.29 Table 9. — Textural parameters 68.38 66.88 70.21 67.16 68.06 64.26 57.79 67.00 70.50 42.57 38.42 64.46 69.17 74.22 77.89 65.33 73.05 75.96 79.21 74.46 67.86 70.42 72.51 72.51 74.41 49.87 51.74 66.02 74.89 50.68 Core No. E-8 . E-11 E-12 E-14 E-15 E-18 E-20 E-21 E-21 E-21 E-21 E-21 E-21 E-21 E-21 E-22 E-22 E-22 E-22 E-22 E-22 Interval (cm.) Median Standard Skew- Kurto- Mean dev, ness sis 2-5 8.20 8.03 3.00 -0.03 0.90 2-7 8.55 8.58 2.72 0.05 0.93 0-5 7.80 7.97 2.60 0.13 0 91 0-4 4.60 5.70 3 33 0.47 0.87 0-5 7.00 6.97 3.40 0 07 0.72 0-4 8.40 8.40 2.73 0.01 1.00 0-4 8.00 7.87 2.73 -0.05 1.03 0-3 8.35 8.10 2 69 -0.16 1.10 3-7 8.65 8.47 2.63 -0.12 1.01 14-17 925 8.97 3.37 -0.10 0.96 17-20 9,20 9.03 3.14 -0.07 1.02 20-23 9.25 9.07 3.12 -0.07 1.03 32-36 8.55 8.08 3 88 -0.10 0.81 36-39 9.20 8.67 3 52 -0.18 0.96 39-42 8.45 7.72 3 96 -0.18 0.77 0-2 8.45 820 291 -0.06 0.96 10-12 9.15 9.05 3.10 -0.03 1.06 20-22 9.00 9.17 3.17 0.07 1.00 31-33 9.10 8.75 3.18 -0.13 1.05 40-42 9.15 9.22 3.02 0.02 1.03 51-53 9.10 8.65 3.41 -0.16 1.06 32 Table 9. — Continued Core No. Interval (cm.) Standard Skew- Kurto- Mean dev. ness sis Table 10. — X-ray diffraction data for (1) black crusts from core E~26, 8-7, cm. and (2) brown earthy sub- stance from core E-26, 7-10 cm. E-25 0-3 E-25 3-10 E-25 10-13 E-25 13-15 E-25 15-19 E-25 ■ 19-22 E-25 22-30 E-25 30-33 E-25 33-40 E-25 40-43 E-25 43-50 E-25 50-54 E-26 0-3 E-26 3-7 E-26 7-10 E-26 10-13 E-26 13-15 E-26 15-19 E-26 19-22 E-26 22-25 E-26 25-28 E-26 28-31 E-26 31-34 E-26 34-37 E-26 37-40 E-26 40-43 E-26 43-47 E-28 0-3 E-28 10-13 E-28 20-23 E-28 23-26 E-29 0-3 E-29 7.5-10.5 E-29 19-22 E-29 29-32 E-30 0-3 E-30 7.5-11.5 E-30 20-23 E-30 30-33 E-30 36.5-40 E-31 0-3 E-31 8.5-11.5 E-31 20-23 E-31 30-33 E-31 40-43 E-32 0-5 E-33 0-4 E-34 0-5 E-35 0-5 E-36 0-5 8.95 8.88 2.22 -0.10 1.18 9.30 9.23 2.19 -0.10 1.19 9.50 9.55 2.44 0.02 1.02 9.45 9.53 2.26 -0.00 1.12 9.15 9.22 2.07 -0.02 1.12 9.70 9.72 2.63 -0.00 1.00 9.40 9.43 2.16 -0.02 1.08 9.85 9.85 2.84 -0.02 1.05 9.45 9.48 2.14 0.02 0.98 9.75 9.80 2.47 -0.01 1.08 9.70 9.73 2.42 -0.00 1.02 9.80 9.87 2.57 0.00 1.02 8.70 8.40 2 85 -0.20 1.29 8.70 8.52 2.64 -0.12 1.09 9.10 8.85 2.72 -0.14 1.09 9.40 8.40 3.18 -0.02 1.19 9.30 8.73 3.59 -0.20 1.16 9.40 9.18 3.08 -0.14 1.15 9.35 8.93 3.31 -0.18 1.15 9.30 8.90 3.23 -0.17 1.12 9.20 8.90 3.14 -0.14 1.11 9.10 8.58 3.39 -0.19 1.10 9.40 8.97 3.11 -0.19 1.12 9.20 8.73 3.34 -0.16 1.09 9.25 8.72 3.36 -0.18 1.03 9.15 8.48 3.42 -0.22 0.88 8.55 8.17 3.61 -0.09 0.77 9.40 8.93 2.59 -0.31 1.29 9.35 9.10 2.68 -0.18 1.16 7.00 6.90 4.25 -0.07 1.01 6.70 6.97 3.91 0.05 1.03 8.70 8 65 2.37 -0.08 1.21 9.00 8.88 2.24 -0.09 1.07 9.40 9.32 2.25 -0.08 1.13 9.60 9.62 2.26 -0.02 1.10 8.80 8.83 2.14 -0.06 1.19 9.50 9.53 2.48 0.01 1.01 9.50 9.50 2.35 -0.02 1.06 9.75 9.80 2.40 0.01 1.08 9.60 9.60 2.48 -0.03 1.05 8.45 8.42 2.37 -0.07 1.10 9.20 9.10 2.56 -0.06 1.06 9.55 9.35 2.85 -0.10 1.07 9.60 9.43 2.77 -0.11 1.06 9.55 9.42 2.53 -0.14 1.16 7.95 8.02 2.97 0.10 0.84 8.10 8.33 3.16 0.06 0.94 8.40 8.50 2.44 0.07 0.99 8.35 8.28 3.07 0.07 0.86 8.10 8.08 2.96 0.05 0.88 Observed pattern Observed intensity (1) Observed pattern Observed intensity (2) 7.08 M 4.28 VW 3.62 VVW(b) 3.37 S 3.18 WW 2.95 WW 2.50 M 2.26 W*°^ 2.16 WW 1.97 WW 1.82 M 1.65 WW'^^ 1.54 VW 1.43 W 1.42 m'^> 1.38 M 1.295 WW 1.225 WW 1.180 WW 5.52 4.58 4.25 3.35 3.18 2.96 2.80 2.59 2.39 2.30 2.11 1.99 1.82 1.67 1.61 1.55 1.50 1.38 1.295 1.195 1.05 W(d) M M(b) S W M MS Ms'''' M W (b) W W M VW VW w w M VW VW WW Note. — "d" and "b" represent diffuse and broad peaks; WW, VW, W, M. MS. S are very very weak, very weak, weak, medium, medium strong, very strong intensities respectively. 33 Table 11. — Comparison of X-ray data for pellets sepcv- rated from core E-31, 20-23 cm,, with data for the mineral vivianite Table 12. — Distribution of iron and manganese in core E-26 Observed pattern 7.95 6.78 4.91 4.55 4.32 4.07 3.85 3.35 3.21 2.97 2.71 2.64 2.53 2.43 2.32 2.23 2.18 2.07 1.93 1.91 1.82 1.77 1.68 1.58 Observed intensity M vs M W w vw M M M S s vw M M W W w w w w vw vw w w Vivianite (ASTM No. 3-0070) dA I/I, 8.00 6.80 4.91 4.50 4.32 4.09 3.84 3.65 3.33 3.20 2.97 2.71 2.64 2.52 2.42 2.31 2.23 2.19 2.07 2.01 1.96 1.92 1.89 1.82 1.78 1.67 1.59 1.55 1.52 1.49 1.47 27 100 40 13 4 13 40 5 3 53 67 67 8 33 40 27 20 20 23 33 20 11 13 40 23 7 11 12 7 Core No. E-26 Interval (cm) Fe (weight percent) Mn (weiTht percent) Mn/Fe 0-1 1.19 0.82 0.69 1-2 1.24 0.94 0.76 2-3 1.19 2.45 2.06 3-4 1.12 6.20 5.54 4-5 1.24 2.35 1.90 5-6 1.23 2.45 1.99 6-7 1.24 3.20 2.58 7-8 2.65 1.65 0.62 8-9 4.50 0.15 0.03 9-10 3.20 0.12 0.04 10-11 0.80 0.06 0.08 11-12 0.72 0.05 0.07 12-13 0.78 0.04 0.05 13-14 0.32 0.04 0.12 14-15 0.62 0.07 0.11 15-16 0.66 0.04 0.06 16-17 0.38 0.03 0.08 17-18 0.52 0.15 0.29 18-19 1.20 0.26 0.22 19-20 1.55 0.34 0.22 20-21 1.50 0.30 0.20 22-23 0.59 0.16 0.27 23-24 1.95 0.31 0.16 25-26 1.67 0.24 0.14 27-28 1.67 0.12 0.07 29-30 0.64 0.04 0.06 30-31 0.49 0.04 0.08 34-35 1.75 0.10 0.06 36-37 1.35 0.08 0.06 45-46 0.32 0.02 0.06 46-47 0.32 0.03 0.09 34 Table 13.- -Distribution of iron and manganese in core N-H8 Table 14. — Continued Core No. Interval (cm) Fe ( weight percent) Mn (weiff)lt percent) Mn/Fe N-148 0-1 1-2 2-3 3-4 4-6 B-6 6-7 7-8 8-9 9-10 10-11 11-12 12-13 13-14 14-15 15-16 16-17 17-18 18-19 19-20 20-21 30-31 40-41 43.5-44.5 1.46 1.53 1.50 1.48 1.52 1.50 1.41 1.45 1.39 1.76 5.45 3.45 3.55 2.65 2.00 1.50 0.99 1.02 0.98 0.87 0.31 0.48 0.73 1.47 0.43 0.51 0.54 0.78 1.25 2.10 1.85 1.45 1.23 1.58 0.36 0.25 0.23 0.36 0.35 0.23 0.38 0.25 0.23 0.18 0.04 0.01 0.01 0.01 0.29 0.33 0.36 0.53 0.82 1.40 1.31 1.00 0.88 0.90 0.07 0.07 0.06 0.14 0.18 0.15 0.38 0.23 0.24 0.21 0.13 0.02 0.01 0.01 Table 14. Core No. -Nondetrital iron and manganese in surface sediments Interval (cm) Fe (weight percent) Mn (weight percent) Mn/Fe E-8 0-1 1.76 0.30 0.17 E-11 0-1 1.46 0.18 0.12 E-12 0-1 1.22 0.28 0.23 E-14 0-1 1.04 0.12 0.12 E-15 0-1 1.18 0.39 0.33 E-18 0-1 2.84 0.52 0.18 E-20 0-1 3.04 0.85 0.28 E-21 0-1 1.02 1.15 1.13 E-22 0-1 2.44 0.47 0.19 E-25 0-1 1.22 2.62 2.15 E-26 0-1 1.19 0.82 0.69 E-28 0-1 1.21 0.53 0.44 E-29 0-1 1.33 0.80 0.66 E-30 0-1 1.44 0.69 0.48 E-31 0-1 1.76 1.45 0.82 E-32 0-1 0.43 0.01 0.02 E-33 0-1 1.98 0.18 0.09 E-34 0-1 1.60 0.32 0.20 Core Interval No. (cm) E-35 0-1 E-36 0-1 N-1 0-3 N-12 0-7.5 N-13 0-12.5 N-23 0-7 N-28 0-12 N-29 0-7 N-41 0-11 N-61 0-2 N-77 0-3 N-101 0-1 N-102 0-1 N-107 0-1 N-108 0-1 N-109 (') N-110 0-1 N-112 0-2 N-113 0-3 N-114 0-3 N-115 0-3 N-116 0-1 N-117 0-3 N-118 0-3 N-122 0-1 N-123 0-1 N-124 0-1 N-125 0-1 N-126 0-1 N-131 0-1 N-134 0-2.5 N-135 0-1 N-136 0-3 N-137 0-3 N-139 0-2 N-141 C) N-142 0-3 N-143 0-2 N-144 0-4 N-147 0-4 N-148 0-3 N-149 0-3 N-151 (•) N-152 0-3 N-153 C) N-154 0-2 N-155 0-3 N-156 0-4 N-157 (•) ' Grab. Fe (weight percent) Mn (weight percent) Mn/Fe 1.19 0.28 0.23 1.36 0.24 0.18 1.30 2.26 1.73 1.32 1.90 1.44 1.40 2.25 1.61 1.40 3.85 2.75 1.70 1.65 0.97 1.90 0.68 0.36 2.06 0.77 0.38 1.32 0.20 0.15 2.00 0.15 0.08 1.23 0.33 0.27 0.83 0.17 0.20 0.90 0.18 0.20 1.26 0.30 0.24 0.41 0.11 0.27 0.82 0.17 0.21 0.64 0.10 0.16 1.42 0.48 0.34 1.22 0.28 0.23 0.99 0.30 0.30 1.88 0.21 0.11 1.06 0.28 0.26 1.11 0.26 0.23 1.00 0.22 0.22 0.87 0.20 0.23 1.20 0.32 0.27 1.70 0.20 0.12 1.78 0.50 0.28 1.18 0.18 0.15 0.52 0.14 0.27 1.24 0.60 0.48 1.19 0.30 0.25 1.04 0.24 0.23 0.97 0.10 0.10 1.19 0.38 0.32 1.62 0.40 0.25 1.97 0.24 0.12 1.19 0.35 0.29 1.34 0.65 0.48 1.01 0.36 0.36 1.14 0.30 0.26 0.94 0.22 0.23 1.35 0.30 0.22 0.58 0.07 0.12 1.91 0.72 0.38 1.42 0.28 0.20 0.90 0.31 0.34 1.42 0.24 0.17 35 Table 15. — HC-extractable iron and manganese in surface sediments of southwestern Kara Sea (from Gorshkova, 1957) station No. Depth (m) Interval (cm) Mn Fe Mn/Fe 1 104 0-4 0.08 4.91 0.02 4 158 C) 1.57 9.35 0.17 5 145 0-5 0.87 6.88 0.13 6 62 (') 0.13 2.31 0.06 7 62 (■) 0.36 3.99 0.09 8 114 0-2 0.62 4.74 0.13 9 130 0-3 0.29 4.00 0.07 10 145 0-5 0.27 3.89 0.07 11 200 0-4 0.19 5.85 0.03 13 280 (') 0.18 3.09 0.06 14 72 0-5 0.13 2.04 0.06 15 170 0-10 0.71 4.19 0.17 16 104 (■) 0.32 3.26 0.10 17 147 0-2 0.47 4.21 0.11 18 75 0-2 0.28 2.82 0.10 19 48 (') 0.24 0.27 0.09 22 28 (') 0.04 1.44 0.03 23 31 0-3 0.16 6.63 0.02 24 37 0-5 0.07 5.47 0.01 30 370 0-3 0.93 9.10 0.10 31 230 1-5 0.47 5.24 0.09 34 70 1-4 0.27 3.47 0.08 35 395 0-5 0.71 5.04 0.14 37 69 0-3 0.06 1.89 0.03 38 75 0-2 0.06 2.86 0.02 40 32 C) 0.03 2.18 0.01 41 150 0-3 1.44 5.25 0.27 42 42 1-3 0.21 3.40 0.06 43 28 0-5 0.04 2.24 0.02 44 215 0-2 1.31 4.84 0.27 45 75 0.04 2.53 0.02 » Grab. ■ft U.S. GOVERNMENT PRINTING OFFICE: 1971 0—411-511 36 S3^' AA