/i 97 i, oe ALLAN HANCOCK PACIFIC EXPEDITIONS VOLUME 27 PART 1 SUBMARINE CANYONS OF SOUTHERN CALIFORNIA PART I TOPOGRAPHY, WATER, AND SEDIMENTS K. O. EMERY and JOBST HULSEMANN DATA LIBRARY & ARCHIVES Woods Hole Oceanographic institution aan | ‘ Pe NE RR RR TT eR ACORN RT - UNIVERSITY OF SOUTHERN CALIFORNIA PRESS LOS ANGELES, CALIFORNIA 1963 HANCOCK PACIFIC EXPEDITIONS PART 1 ALLAN VOLUME 27 SUBMARINE CANYONS OF SOUTHERN CALIFORNIA PART I TOPOGRAPHY, WATER, AND SEDIMENTS K. O. EMERY and JOBST HULSEMANN HUT DT MBL/WHOI MOM UNIVERSITY OF SOUTHERN CALIFORNIA PRESS LOS ANGELES, CALIFORNIA 1963 SUBMARINE CANYONS OF SOUTHERN CALIFORNIA Part I TOPOGRAPHY, WATER, AND SEDIMENTS by K. O. EMERY and JOBST HULSEMANN ALLAN Hancock PAciFic ExPEDITIONS VOLUME 27 Part I IssuEeD: May 10, 1963 PRICE: $3.00 UNIVERSITY OF SOUTHERN CALIFORNIA PRESS Los ANGELES, CALIFORNIA TABLE OF CONTENTS Introduction . Acknowledgments Topography . Methods Characteristics Lithology and age Water . Sediments . Sampling Methods . ‘Texture Calcium carbonate Organic matter Comparison with sediments of adjacent areas Summary and Conclusions Literature cited . Appendices 21. 22. LIST OF FIGURES . Index map showing areas sounded and sampled off southern California . . Plot of difference between wire depth and sonic depth corrected for sound velocity . . Hueneme Canyon . . Mugu Canyon Dume Canyon . Santa Monica Canyon . Redondo Canyon . . San Pedro Sea Valley . Newport Canyon . . La Jolla Canyon . . Coronado Canyon . Santa Cruz Canyon . Santa Catalina Canyon . San Clemente “Rift Valley” . Tanner Canyon . Relationships of wall steepness and height to slope of canyon axes . Profiles of submarine canyons compared with lithology where known . Positions and depths of water samples in six canyons at stations shown by open circles in Figures 3 through 15 . Characteristics of water in Redondo Canyon . Relationship of median diameters of samples from submarine canyons to frequency of occurrence, sorting coefficient, and contents of calcium carbonate and Kjeldahl nitrogen : Results of separate determinations for organic carbon on sub-samples, based on (1) analysis for carbon in residue from carbonate analysis, and (2) on analysis for total carbon minus carbonate carbon Comparison of carbon and nitrogen analyses on samples from submarine canyons « 4 ges 4 om eo : 55 58 59 LIST OF TABLES 1. Characteristics of water in submarine canyons 2. Capitella bottoms in canyons . 3. Sediments of submarine canyons and other environments 38 53 60 wy SUBMARINE CANYONS OF SOUTHERN CALIFORNIA Part I. Topography, Water, and Sediments by K. O. Emery and Jobst Htilsemann INTRODUCTION For many years submarine canyons have been known off southern California and have been studied in varying degrees of detail, largely by F. P. Shepard and his students and colleagues. Most of this work consisted of studies on topography (Shepard and Emery, 1941), lithol- ogy (Emery and Shepard, 1945), and general sediments (Cohee, 1938). Hydrographic and biological work has been sketchy. Some recent studies by Gorsline and Emery (1959) indicated the common presence of sandy floors along the canyon axes which mark the route of turbidity currents that move coarse sediment from beaches and inner shelves outward to the deep basin floors (Emery, 1960a). This preliminary sampling also suggested that benthic animals on the floors of the canyons differ from those at the same depths outside the canyons. Differences in environ- ment, such as coarse sediment, moving sediment, or abnormal water conditions, may be important biological controls in the canyons. Thirteen of the largest submarine canyons were selected for special studies of the topography, sediments, hydrography, and benthic biology. Many other canyons are present in the region, some of them larger than the smallest one described in this report. Among these fairly large but relatively poorly known canyons are several between Mugu and Hue- neme Canyons, San Gabriel Canyon, Oceanside Canyon, Carlsbad Can- yon, and several north and east of San Nicolas Island. These canyons were omitted not because they are unimportant, but because of time limitation and because the 13 canyons which were selected probably cover the range of variation expected within the fields of investigation. Basin slopes in the region also contain related but smaller features termed sea gullies (Buffington, 1951, in press; Emery and Terry, 1956) ; perhaps several thousand are present. 1 2 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL: 27 ACKNOWLEDGMENTS Most of the field work was accomplished between December 1959 and May 1960 (Stations 6776 to 7055) through the aid of National Science Foundation Grant G-9060. A few samples collected during 1961 and 1962 were by-products of an additional National Science Founda- tion Grant G-12329. Many of the data for Santa Monica, Redondo, and San Pedro Canyons were collected during short cruises extending back to 1951; most of these cruises were financed by Captain Allan Hancock, but some were part of a contract for studies of Santa Monica Bay for Hyperion Engineers, Incorporated. Appreciation is due J. R. Grady for his careful analyses for nutrients in the waters and to many other students of the Department of Geology who participated in the ship work during class or special field trips. All field measurements were made aboard the Allan Hancock Foundation’s research vessel VELERO IV. TOPOGRAPHY Methods The 13 submarine canyons of this study occur along the mainland and off islands and banks (Fig. 1). For each of them 6 to 13 sounding lines were run at right angles to the canyon axis, as shown by naviga- tional charts, and at approximately equal intervals along it. The lines are long enough to show the relationship between the sides of the canyons and the adjacent mainland or island shelf, basin slope, or basin floor. Soundings were made with the Precision Depth Recorder (Luskin, Heezen, Ewing, and Landisman, 1954) attached to an Edo echo sounder. Instrumental error is less than 1 part in 3000, so the chief error in depth results from variation of the speed of sound in sea water and the reflection of sound from areas of the bottom within the sound cone and shallower than the point directly beneath the ship. The pro- files are based upon soundings uncorrected for sound velocity. Since the echo sounder is calibrated for a sound velocity in sea water of 1463 meters per second and the actual sound velocity for these depths is about 1.2 per cent faster (Emery, 1960b), the profiles are about 1.2 per cent too shallow. More important, however, is the effect of echoes from the sides of the narrow canyons; these often obscure the echoes from the narrow bottom. Comparison of wire depths for samples taken in the canyons with simultaneous echo soundings corrected for sound velocity show that some of the echo soundings are as much as 50 meters too WwW No. 1 EMERY AND HU‘LSEMANN: SUBMARINE CANYONS shallow, with greatest errors in the narrowest part of the canyons (Fig. 2). In contrast, the average difference between wire and echo depths for flat shelves and basin floors is less than about 3 meters. Fig. 1—Index map showing areas which were sounded and sampled off southern California, for which contours, profiles, and sample positions are shown in Figures 3 through 15. H, Hueneme Canyon; M, Mugu Canyon; D, Dume Canyon; SM, Santa Monica Canyon; R, Redondo Canyon; SP, San Pedro Sea Valley; N, Newport Canyon; LJ, La Jolla Canyon; Co, Coronado Can- yon; SCr, Santa Cruz Canyon; SCa, Santa Catalina Canyon; SCI, San Clemente “Rift Valley,’ T, Tan- ner Canyon. Positions were determined at 5-minute intervals by a radar range and bearing on a prominent coastal point, such as a pier end or a steep cliff. Since the ship speed was 9 to 10 knots, positions are about 1.5 km apart. 4 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.2/ In the laboratory the tapes of continuously recorded soundings were reduced to half scale with a pantograph and the reductions were traced directly for Figures 3 through 15. U.S. Coast and Geodetic Survey navigational charts served as the source for contours of the index map for each of the canyons. Characteristics General :—The canyons off southern California have been described previously by Shepard and Emery (1941) and by Emery (1960a) who also summarized the pertinent literature on them. Accordingly, only new data on topography and data needed for the proper interpretation of water characteristics and sediments will be presented here. The canyons occupy parts of three physiographic environments of the sea floor: continental or insular shelf, basin slope, and basin floor. In each environment the canyons present a different aspect. Shelf Portion:—The shelf is largely or entirely crossed by 8 of the 13 canyons of this study. Santa Monica, San Pedro, and Coronado canyons only indent the shelf; however, filled extensions of all three canyons are known on the adjacent land through well borings, and a filled channel across the shelf from the head of San Pedro Sea Valley was discovered by jet borings made by Richfield Oil Company. The other two exceptions are ‘Tanner Canyon which begins deep on the saddle between Cortes and Tanner banks, and San Clemente Rift Valley which is different in many ways from other submarine canyons. Among the 8 canyons which do cross most of the shelf, Hueneme, Re- dondo, and Newport have now-filled extensions on land, as shown again by well borings. Each of the 8 also les off a prominent land valley, except Santa Cruz Canyon which heads into the shelf saddle between Santa Cruz and Santa Rosa islands. Hueneme, Redondo, New- port, La Jolla, Santa Cruz, and Santa Catalina extend in nearly straight courses across the shelves, but Mugu and Dume are broadly curved. The depth of the canyon edge, or lip, is not uniform across the shelves. Transverse profiles across the shelf portions of Hueneme, Mugu, Santa Monica, Redondo, San Pedro, Newport, La Jolla, Coronado, and Santa Catalina canyons (see Figs. 3-15) show a seaward deepening of the canyon edge. This deepening is somewhat greater than the general slope of the shelf and, moreover, the profiles show some lateral slope of the shelf toward the canyons. Both facts mean that the topographic effect of the canyons extends somewhat beyond the narrow gorge of the canyons. No. 1 EMERY AND HULSEMANN: SUBMARINE CANYONS 5 Below the canyon edge, the profiles show steep slopes—too steep in fact for completely satisfactory use of an essentially non-directional echo sounder. he measured slopes are minimal ones; still, as shown by the left-hand part of the top panel of Figure 16, the indicated slopes of the WIRE DEPTH MINUS CORRECTED SONIC DEPTH -25 0 +25 +50 *75 +100 #125 WIRE DEPTH—METERS 1500 Fig. 2.—Plot of difference between wire depth and sonic depth corrected for sound velocity. The dominantly shallower sonic depth is the result of echoes from steep canyon walls which obscure the echo from directly beneath the ship. The sounding differences at sites in canyon axes and on canyon side walls are similar. walls nearest the heads of the canyons are 10° to 40°. Observations made by divers in shallower waters reveal yet steeper, even vertical to overhanging walls. These parts of the submarine canyons probably rep- resent the steepest areas of the sea floor. 6 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 27 Shepard and Beard (1938) reported that the axial slope of Cali- fornia submarine canyons is steepest at the head—14.5°, moderate at the middle—5.5°, and gentlest at the seaward end—4.0°. The new pro- files were made too far from the shallows at the heads of the canyons to cross the steepest part of the canyon axes, but axial slopes which they did encounter in the shelf portions usually exceeded 5°. All except three canyons (Coronado, Santa Catalina, and Tanner) have longitudinal profiles that are concave upward. As shown by Figure 16, there is only a slight correlation between steepness of canyon walls and of canyon axes. Heights of canyon walls in the shelf portion range upward to 480 meters and average about 170 meters. In five canyons (Hueneme, Santa Monica, Redondo, Newport, and Santa Cruz) the greatest wall heights occur at the outer part of the shelves; in all the others, the greatest heights are slightly farther seaward, near the top of the basin slopes. Basin-slope Portion:—Basin slopes in the region average about 8°. The portion of some of the canyons traversing the basin slope is longer than that across the shelf, but for other canyons the reverse is true. All except Newport, San Clemente, and Tanner canyons have broadly curved courses down the basin slopes. For four canyons the curvature is to the right and for six to the left; this curvature appears to be the result of differential erosion along structural irregularities in the basin slopes. Just as for the shelf portions, the intersections of the canyon walls with the basin slopes are not usually abrupt, but the basin slopes bend gradually inward toward the canyons. Indicated steepnesses of the can- yon walls range up to 40°, averaging slightly less than for the shelf por- tion. In both portions the opposite walls exhibit considerable asymmetry, with one-third of all pairs of profiles having one wall more than twice as steep as the opposite wall. Heights of the walls range up to 500 meters and average 170 meters for 79 measurements, the same as the average for the shelf portions of the canyons. The heights of both walls are about equal, except where the canyon lies at the foot of a basin slope. The echograms present a minimum width of the canyon floors be- cause of reflections from the canyon walls, as discussed also by Northrop (1953) for Hudson Canyon. Often a faint echo from a horizontal sur- face can be detected through the traces produced by echoes from the walls. This faint echo, the presence of flat bottoms on some echograms, the collection of several samples from about the same wire depth on a profile across a canyon, plus the observations of divers in shallow water indicate that the canyons in both shelf and slope portions may have flat No. 1 EMERY AND HULSEMANN: SUBMARINE CANYONS 7. floors. The width is uncertain but it is believed to commonly range up to 200 meters. Basin-floor Portion:—At the foot of the basin slopes both the gen- eral bottom topography and the canyons exhibit a change. The general steepness is much less and both contours and samples show that the basin slope is bordered by a broad concave fan or apron built up of sedi- ments carried through the submarine canyons (Gorsline and Emery, 1959; Emery, 1960b). Fans from adjacent canyons may coalesce to form a general bajada-like feature whose steepness ranges downward from about 1.5°. Beyond the fans are basin plains which are so flat that the depth may change only 1 meter in 6 km. Extensions of the submarine canyons have been recognized only across the fans, where they take the form of low winding channels. These channels are bordered by natural levees which often cause the floor of the channel to be higher than the surface of the adjacent fan. Such levees are shown by profiles for Mugu, Dume, Santa Monica, Redondo, San Pedro, Newport, La Jolla, Coronado, Santa Cruz, and Santa Catalina canyons and they may occur at others. The first recog- nition of levees in the region appears to have been by Buffington (1952) for San Pedro, Newport and La Jolla canyons. Heights of the levees above the channels range up to about 50 meters, but 25 meters is prob- ably a better average height. The channels are probably less than 200 meters wide and their axial slopes range from 3° to 0.4°, as shown by the data of Figure 16. Lithology and Age Rocks have been dredged from the walls of many of the canyons. Most common are sedimentary and volcanic rocks of Miocene age (Fig. 17). Pliocene shales were obtained at San Pedro Sea Valley, San Gabriel Canyon (about 20 km east of San Pedro Sea Valley), and Coronado Canyon. Landward extensions of canyons have been filled with Recent sediments. Therefore, the age of the canyons is pre-Recent and at least parts of some of them are post-Pliocene. The strata which crop out on the walls represent seaward extensions of the same strata en- countered in outcrops or in wells on the adjacent land, but not enough samples are available to reveal the tops and bottoms of individual beds or to show whether the beds dip seaward or have structural peculiarities. ALLAN HANCOCK PACIFIC EXPEDITIONS VOLT Fig. 3—Hueneme Canyon. Profiles with (X 19) vertical exag- geration. Insert map with contours in meters shows posi- tions of profiles, bottom samples (solid dots), and hydro- graphic casts (circles). No. 1 EMERY AND HULSEMANN: SUBMARINE CANYONS KILOMETERS 1 0 1 f HUENEME => N nt 1199157 | N aa \ 2OOTHUENEME \ CANYON ; METERS 600 10 ALLAN HANCOCK PACIFIC EXPEDITIONS Fig. 4.—Mugu Canyon. Symbols same as for Figure 3. VOL. 27 No. | EMERY AND HULSEMANN: SUBMARINE CANYONS MUGU CANYON METERS & 600 S00 === KILOMETERS 0 1 a VA 11 12 ALLAN HANCOCK PACIFIC EXPEDITIONS Fig. 5—Dume Canyon. Symbols same as for Figure 3. VOL. 27 No. 1 EMERY AND HULSEMANN: SUBMARINE CANYONS KILOMETERS 1 0 1 200 DUME CANYON 800 14 ALLAN HANCOCK PACIFIC EXPEDITIONS Fig. 6.—Santa Monica Canyon. Symbols same as for Figure 3. VOELZT No. | EMERY AND HULSEMANN: SUBMARINE CANYONS 15 KILOMETERS ot 3 0 4 2 5 6 ae 200 ANTA MONICA 00 CANYON goon 118°30° ip) : vie |: k= Lu = 600 800 16 ALLAN HANCOCK PACIFIC EXPEDITIONS Fig. 7—Redondo Canyon. Symbols same as for Figure 3. VOL. 27 No. 1 EMERY AND HULSEMANN: SUBMARINE CANYONS ty KILOMETERS 1 0 1 2 g) nn T T T T T —T Som 118°30° 256 200}- * : ony +2189 a 2790 5960 2793 \ 2725 -2149 |279, | 2789x3168 \-a1e6 \z194 2729 || 2792\2150 \\-ea16 \e192 ¥. [2474 | e774 21st \ eats \ area S||),6775 |||) 3385 \\2726. \\\2190 \\3163) ie 6 362 SS a5 ou =O N foe) {of oe +) 413169) || | 2727°\\3167! \\\ REDONDO Neen NN CANYON 400 METERS 2432 2420 2405 2322 9, 2 e ° O_-40° th 600 800 oe) ALLAN HANCOCK PACIFIC EXPEDITIONS Fig. 8—San Pedro Sea Valley. Symbols same as for Figure 3. VOL. 27 No. | 200 400 METERS 800 EMERY AND HULSEMANN: SUBMARINE CANYONS 19 KILOMETERS 3 2 1 SAN. PEDRO SEA VALLEY a ALLAN HANCOCK PACIFIC EXPEDITIONS Fig. 9.—Newport Canyon. Symbols same as for Figure 3. VOL. 27 No. 1 EMERY AND HULSEMANN: SUBMARINE CANYONS 21 KILOMETERS o 4 3 2 1 2 3 5 6 7 8 9 T al =i T T T T T NEWPORT CANYON 200 uy oO uJ _— lJ = 400 418°00° Sor 117°50° 45° 600 ALLAN HANCOCK PACIFIC EXPEDITIONS Fig. 10.—La Jolla Canyon. Symbols same as for Figure 3. VOL. 27 NOvaL EMERY AND HULSEMANN: SUBMARINE CANYONS 23 KILOMETERS Ot 3 Z 0 1 a 5 6 7] (4 \ 200 | LA oa = POLE A CANYON WY fag al lJ LJ = 600 5 | 800 1000 ALLAN HANCOCK PACIFIC EXPEDITIONS Fig. 11—Coronado Canyon. Symbols same as for Figure 3. VOL. 27 No. | EMERY AND HULSEMANN: SUBMARINE CANYONS 25 KILOMETERS 2 1 0 1 200 CORONADO CANYON \ CORONADOS| \ Siscanos \ . \ .) METERS @ 00 1000 1200- 26 ALLAN HANCOCK PACIFIC EXPEDITIONS Fig. 12.—Santa Cruz Canyon. Symbols same as for Figure 3. VOL. 27 No. l EMERY AND HULSEMANN: SUBMARINE CANYONS KILOMETERS 3 2 1 ) CANYON 21 28 ALLAN HANCOCK PACIFIC EXPEDITIONS Fig. 13.—Santa Catalina Canyon. Symbols same as for Figure 3. VOL. 27 No. 1 EMERY AND HULSEMANN: SUBMARINE CANYONS 29 KILOMETERS 1 0) 1 200 400 fea] 00 METERS @ 00 30 ALLAN HANCOCK PACIFIC EXPEDITIONS Fig. 14.—San Clemente “Rift Valley.’”’ Symbols same as for Figure 3. VoL. 27 No. l EMERY AND HULSEMANN: SUBMARINE CANYONS KILOMETERS Q 1 ae (Saeed Jn? 4 ‘ss se SAN CLEMENTE ISLAND 200) 400; CLEMENTE vile tie bor VALLEY 800+ 1200 1400 1600 1800 2000\— 31 SZ ALLAN HANCOCK PACIFIC EXPEDITIONS Fig. 15—Tanner Canyon. Symbols same as for Figure 3. VOL. 27 No. 1 EMERY AND HULSEMANN: SUBMARINE CANYONS 400 aD 00 METERS CANYON OOF 4 @ 1000+ 1200 34 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 27 SLOPE OF CANYON AXES 2: oes 2° 08° 06° 4° SLOPE OF CANYON WALLS HEIGHT OF WALLS—M. Fig. 16.—Relationships of wall steepness and height to slope of canyon axes. Symbol L indicates presence of natural levees. No. 1 EMERY AND HULSEMANN: SUBMARINE CANYONS 35 STATUTE MILES '5 20 25 30 FAN OF SANTA CLARA RIVER 4 a LOS ANGELES RIVER-FORMER COURSE ‘| SANTA MONICA ; gees Ce iss CANYON 2400 4 ‘ 4 T REDONDO Pa Onna DUME | ood CANYO, P CANYON | a 4 LOS ANGELES RIVER \GUNSAN PEDRO. 202- Saga See 7 oot SEA VALLEY 0 eee eee ew | we a l f = aie 4 = Ww Wy 400} a= Se pea — - eR SAN GABRIEL RIVER > SAN GABRIEL CANYON i eae) = 1200 P Pp | x 2400 ‘ i ‘ M__SANTA ANA R/IVER-FORMER COURSE wi NEWPORT = LA JOLLA CANYON 1200 ——————> SANTA CATALINA CANYON SANTA C ie) o RUZ TANNER CANYON CAN, 2400) UZ ia ose g eg ie Fig. 17.—Profiles of submarine canyons compared with lithol- ogy where known. Symbols are as follows: arrow, shore- line; K, Cretaceous; E, Eocene; M, Miocene; P, Plio- cene; Q, Quaternary; R, postglacial (on sea floor letters show sites of dateable rock samples). From Emery (1960a, fig. 48). WATER Those who have spent much time aboard ship watching traces be- ing drawn by echo sounders frequently observe echoes from dense schools of fish which are often present at the tops of slopes, including those at the sides and heads of submarine canyons. Some verification is provided by the reportedly greater catch of fish at the head and sides 36 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 27 of the canyons than on the nearby shelf. It has been suggested that fish are concentrated in these areas because of the presence of abundant food brought by currents from deep in the canyons. Many of the fish caught from piers at the heads of Redondo and Newport canyons are species characteristic of deep cold water, confirming the observation by some skin divers that water may be colder at the head of a canyon than at either side and that at times the water appears to be rising from the canyon. A few current-meter measurements in six canyons of the area (Shepard, Revelle, and Dietz, 1939) showed flows in the direction of the canyon axes but with no preference for up or down canyon. Possibly the water moves too slowly to be indicated reliably by such meters; a better technique might be the measurement of properties of the water itself. Two to eight water stations were occupied along the axes of most of the 13 canyons at positions shown by open circles in Figure 3 through 15. Each station was positioned over the canyon axis by first making a topographic profile and then by stopping the ship at such a position that it would drift over the deepest point of the profile by the time that water-sampling gear had been lowered. In a few instances the drift varied so that the station was slightly to one side of the axis. Water samples were collected in Nansen bottles carrying two protected re- versing thermometers. In Redondo Canyon a series of four water samples were obtained at each station just above the bottom through use of a bottom water sampler described by Rittenberg, Emery, and Orr (1955). For each sample, temperature was corrected from the reversing ther- mometers, salinity was computed from standard titration for chloride, oxygen content was measured by Winkler analysis, and contents of sili- cate, phosphate, and nitrate were determined by standard colorometric methods using a Beckman DU spectrophotometer. The results are listed in Table 1 for the eleven canyons which were sampled. Profiles of six canyons with positions of water samples are presented in Figure 18, and more completely with water characteristics for Redondo Canyon in Figure 19. The measurements show no marked difference in the character of the water at the canyon head from that near the seaward end of the canyon. The water is also within the range of seasonal and areal varia- tion of that in the adjacent basins (Emery, 1954). Close examination of Table 1 and Figure 19, however, does show some slight inclination No. 1 EMERY AND HU‘LSEMANN: SUBMARINE CANYONS 37 of the isopleths in a few of the canyons. At Redondo Canyon the tem- perature and oxygen content is higher and the salinity and nutrients are lower near the head than farther seaward. This difference is just what is to be expected of local upwelling. A similar conclusion is indicated by the less complete data at Dume Canyon, but on the other hand possi- ble downwelling may have occurred at Mugu and La Jolla canyons. Clearly, upwelling was not marked at the times of the surveys, but then the wind and sea conditions were fairly calm at these times. At times of strong winds, movements of water along the canyons may be more intense. It seems evident that the water is not of such unusual character as to present an abnormal environment for benthic animals; thus any ab- normalities in size of individuals or groupings of the fauna must be due to some aspect of the environment other than the water within the canyon. A major abnormality in the benthic fauna is indicated by the fact that 22 samples from six canyons (Table 2) consist almost exclusively of Capitella, a polychaete worm which ordinarily lives in estuarine water (Hartman, 1962). These same samples are free of marine worms and of other marine animals except carnivores such as squid, which may not really inhabit the sites. Since Capitella lays its eggs in the tubes in which it lives, wide dispersion through sea water is unlikely. It is sug- gested that the samples represent sites at which fresh water escapes into the ocean from aquifers which have been intersected by cutting of the canyons. Escape of fresh water is known to occur from many nearshore areas of the sea floor of the world. Accounts of its escape from sub- marine canyons go back at least to Benest (1899). Johnson (1938- 1939) even postulated an origin for submarine canyons on the basis of submarine erosion by escaping ground water, but his concept is now gen- erally considered less plausible than others. It is quite reasonable that a submarine canyon should be a local focus for escape of ground water because it is the farthest landward point of outcropping horizontal strata, and thus a point of steep pres- sure gradient of confined waters. The coarse sediment which floors the canyon should form no impediment. The rate of escape of the water is likely to be so low that a dilution of the overlying sea water cannot be detected. Thus, the benthic fauna may be the best indicator of escaping fresh water. At shallow depths escape is less likely, at least for Hueneme and Redondo canyons, owing to probable sea-water intrusion into aqui- fers produced by artificially lowered water tables of the adjacent land. voL. 27 ALLAN HANCOCK PACIFIC EXPEDITIONS 38 *INO}JUOD WI-QOT WoI adULISIC y o +Z'0 Or —~ 6S'T wz (T/[u) uadAXO 2 Lz Oz SZ"bs Oz & — e% Zz — 60°FE we OCt«S (T/V-37) areydsoyg (0%) Aarurpes a 9 SE Oz 6V'Z oy se — cf 72Z — 97°8 we (T/V-37) a3ear]Is (D.) anjesradwa f, = 0 0 0 0 (W) sixe sAoqy 64 444 64 +£Z (wi) won0g 9°8 8'I 9°8 ¥8'T (wy) aouRystq +189 £189 +189 £189 uonEIS 6S6I J9quis.0q{ £7 NOANYV7) ININAN FT SNOANV?) INTYVWANS NI WaLV AA AO SOLLSTYALOVUV H7) fata 39 EMERY AND HULSEMANN: SUBMARINE CANYONS No. 1 02 69b zs°0 69+ 02 8I gS€ +5°0 90° ES€ st Lt E81 10'T = est rat a rat TOT IST $0°% 2L'2 101 V0 = Z'0 0 = = _ 0 (T/¥-37) ae.3IN (T/[u) waBxO 6% 69b TEbE 69b 8% Le gSé EZ'E 02'be £S€ 2 9°% est 60°bE 60°bE est 4 Ard V2 TOT 68°E£ L6°EE 98°E€ TOT s‘0 $0 9°0 0 FEE SS°EE LS'EE 0 (T/v-37) areydsoyd (°%) Aarurpes +11 69¢ 129 69> 96 18 gSé SZ L OL. ESE 29 £9 est 85°8 0s°8 £81 Sv Ts S¥ TOT S46 126 Z9°6 TOT 9 S L 0 9'+1 z+ O'+T 0 (T/V-37) a3eot[Ig (DO.) ainjesadua J, 0 0 0 0 0 0 (uw) stxe aaoqy +8 696 9IT +8 69€ OTT (ui) Wonog ty 61 0°0 ty 61 00 (wy) aourrstqd 8069 L069 9069 8069 L069 9069 UOHRIS 0961 YP cl NOANVZ) NOAYJT (a) wwdaq (a1) yideq (w) wideq VOL. 27 ALLAN HANCOCK PACIFIC EXPEDITIONS 40 0z 6£S 820 6£S vy Ze 61 ZLE _— 68°0 Cli meS LI ro> o> +02 LT 6ST 09'T 107i 6 10 10> 16 9T'E IV'e Ile 16 ic} Z'0 10 10 0 — = — 0 as (T/V-37) aeIN (T/lw) uedhxQ a2 6£S PEE 6£S 9°7 9°2 ZLE EZ'bE AS ze (ae 0°72 £7 +02 LO'bE ITE Elbe +02 ST st cr 16 ELES 69°EE LL EE 16 = z'0 £0 z'0 0 £S°EE LS'°SS LS°EE 0 & (T/v-37) ajeydsoyg (9%) Ajrurpes 6z1 6£S 96'S 6S = 98 8 ZLE Or'Z rays cle. 4S 19 +9 +9 +02 95°8 94°8 9+°8 +02 = zs SE SE 16 60°01 90°01 £T'O1 16 3 + Z z 0 vl L'vt 8'+1 0 = (T/V-37) axeotIg (D.) aanjeradwa J, 0 a2 02 0 $9 02 (ul) sIxe aAoqy 85S L8E 022 855 L8E 022 (wi) wonog Es ST 70 Lg ST z'0 (wy) aust $689 +689 £689 $689 +689 £689 UOTIEIS O96T TEIN OF NOANVD AWNG 41 EMERY AND HULSEMANN: SUBMARINE CANYONS No. | +0°0 $98 £0°0 89L = £3°T Leb Grd = Ors Z61 SS"b = a 0 (J/[w) uadkxg 9°¢ $98 +98 Sg 892 bE'bé 89L — OF Leb = 86°E£ itp = = BT Z61 = ee LLEé Z61 = = = 0 = = _ 0 (I/v-87) aieydsoyg (°%) Aarures SOT L8 $98 A ST's +98 56 = 89L 61'S = 892 = LE Lt = 90°8 Ltb aa = SZ Z61 = — 12°6 z61 ae = — 0 = — — 0 (T/V-87) aqeoryig (O.) aanjesadwa 7, 0 0 0 0 0 0 (WI) sIxe sa0qy 068 8Sb +02 068 8S +02 (wi) wonog LL2 Z'6 01 VLZ 26 OT (wy) aourIstq 96L9 £819 78L9 9649 £829 Z8L9 UONEIS OSG) 42qms 2 C0c NOANV*) VOINOJ, VINVS (w) twdaq (ut) qidaq (uw) wydaq ALLAN HANCOCK PACIFIC EXPEDITIONS VOLoZ7 42 TSE Z09 = FE'vE 8LS — — EE bE LIS — = — — tr'te Eb'be 69¢ 8E'rE Pete 67 +E — 67'bE 8E'bE SOE — ET'tE 9UHE — — 9E'bE 6ZZ — — — — = — LE'VE 761 7 te OTE ZOE 00'rE oe SZ+E 9E'bE ZS _— — — — a — — 60'KE £6 — 98°E£ ELS ELS — OT'bE SOE t0'bE 9L TLS — — 09° LESE — Z8°EE 8k O£ — Z9'EE 09°E£ 09° Slee 69°EE SLES LLES rat BLEE 99°EE 09°EE Z9'EE BLES SLE LLES Slee 9 OSE $9'EE tO'EE 99°EE O8'££ SLES PBF SLES 0 (0%) Ayrurpes 69£ 80°8 1£°8 +£'8 — 1£'8 18°Z SOE — 6L'8 L8°8 _ — 1Z°8 6ez _ _— _— _ = = 761 $0°6 +0°6 016 60°6 —_ 73°8 778 Zs — — —_ — — _— — £6 — — — a — 716 S16 91°6 9L +8°€1 — — 68°71 ZV'st _— Str 0S‘0T O£ — 6ST 08'+T 8E'bT Test 61'ET 60°11 98°01 I 67°91 — £9'°ST — 9T'9T 88°ST +0°91 LOLI 9 6'9T + LI O'LT +91 SOT 691 O'LT LA 0 (D.) ainjeraduia 7, 0 0 0 00T O£ 0 0 0 (WI) sIxe aAoqy £09 8L5 LIS 99¢ OLE OLE £61 +6 (Wi) Wo}0g z+ [ad SOT 9°8 L’9 Liv 61 1'0 (wy) aueIsIq 89Zb OLZr ILZv CLeb ELer +LZr SLZv 9LZ UOTIEIS 9c6] 2uNf 8g NOANV7) OGNOdIY (uw) mrdaq (a) wadaq 43 EMERY AND HULSEMANN: SUBMARINE CANYONS No. | 89 z09 a 85 87S = as ss LIS — — — -- tb 8b 69 LE 9¢ 8b = ce 6£ SOE — £¢ £¢ = = LE 6772 — — — — = — SE Z61 Ig 92 1¢ If — ££ Ov Zst = Se — — = = — 0£ £6 8 — +2 +2 _— 7 lz IE 9L —- — — 6 6 — 0z 0z Of€ L L 9 S 9 L 91 LI 81 + + S S + L S 9 9 + + is 9 S 9 9 9 0 (T/V-37) ayers ££°0 — — — z09 — 0+'0 — a BLS _— — 6£°0 — LIS — — — -- +6'0 09°0 69¢ z3°0 6I'T SIT _ 88°0 — SOE — etl 95°T — _— 620 62z = os es ee —_ — Z61 Cot — 66'T 80°Z _— 68°0 LVI zst — — — — — — — 6V'Z £6 — 0L'Z 787 6S'T — RS 677 +1'Z 9L — — a 68°b Z0°S — Sie +6'Z O£ S2's 0£°9 79 8£°9 c's $8°¢ LS'€ O£'€ 8 Z1°9 73'S 679 819 97°9 SS'°¢ 10'S O1'9 9 L8°S $6'°S +6°S L0°9 94'S +h'S O19 19°S 0 (T/1™) uadfxO 0 0 0 001 O£ 0 0 0 (WI) sIxe aAoqy £09 8Z5 LIS 99€ OLE OLE £61 +6 (ur) wWo}0g Z'+1 Got S‘Or 9°8 “9 Lt ST 10 (wry) aouRIsTC 897 OLZ> ILzb ZLZb £7 tL7r SLZb 9L7b UOT}EIS ( panuruod ) NOANV7) OGNOdd y (a) wrdaq (uw) widaq VOL. 27 ALLAN HANCOCK PACIFIC EXPEDITIONS 44 (a) dog 9°¢ 209 — 9°€ BLS — — S'€ LS — — — — S*E Lie 69£ Le Lz AS = 8°72 62 SOE — SZ 9°2 — aaa Vg 622 a = = — = = 4 761 SZ 0% co £7 os Ee 4 ZS — _— — _— _— — — UZ £6 £0 — aA v2 — Lt ve v2 9L 2 = = or 8°0 a 0°72 61 3 50 +0 a) £°0 £0 9°0 8T rag 8I £0 £0 £'0 £'0 +0 Z'0 SO +0 9 £'0 £0 £0 £0 +0 S°0 £0 £'0 0 (1/V-37) ayeydsoyg 0 0 0 001 Of 0 0 0 (tu) sixe aaoqy £09 8LS LIS 99§ OLE OLE £61 +6 (wi) wo0g ZtT Let SOT 9°8 a) LY 61 10 (wy) sue stg 89¢b OLZr IL@p ZLev Elev +L@r SLey 9Ler UOTeIS (panurjuod ) NOANV7) OGNOd4 Y 45 SUBMARINE CANYONS EMERY AND HULSEMANN No. l 67 1Z zz £2 0Z gt oT ST 02 gT tr St € + + (T/V-87) ayeIIN Lg 67 Ce Vs ~- z¢ 9°72 +7 97 (a 0°? CC Vl Sal oT (T/v-87) ajeydsoyg 8ST TAL €ZI 18 £8 98 €$ 95 9S 6£ LE SE el (Al § a (T/V-87) ayeorytg 0 0 0 789 6S +06 0°8 LS \Gr4 8589 L589 9589 OL) st’0 999 ees 62°0 0£'0 ££S 99€ £20 08°0 8Z°0 99€ gl cLt 881 L0°C c6'T v0'C cLt 91 16 TO'e LOE See t6°C 16 aa 0 £6°S 88'S cL’s — 0 (T/1u) ue34xO 999 EEbE 999 ££ LOE SZ'HE €£S 99¢ PvE SI'ts OZ bE 99€ 97 ZL S6°ES S6°EE 96°C 68°EE ZLI 0'2 16 69° CESS 69°C IL ES 16 _— 0 LOEE Ores 6r' EE — 0 (0%) Aarurpes 999 vE's 999 €£$ 779 779 €£$ 99¢ er Cord 9F'L 99¢ 99 Col 00°6 116 83°8 16°8 ZL th 16 +L°6 £6'6 06°6 7L'6 16 -— 0 ++I SET ra a 0 (D.) einjveradwia y, 0 0 0 0 0 (uw) sIxe aA0qgYy L81 789 6+S +0v L81 (wr) wonog Z'0 0°8 iS Ig. Z'0 (wy) aouRystq $$89 8589 L589 9589 $89 UOTRIS 096] Arenizqay CT AGTIVA VIS OUdAg NVS (uw) qydaq (a) wideq (w) wadaq VOL. 27 Z 9% (eo) Of Lzz A LAT z3'T 83°T 4 8z'0 0£°0 €5°0 Oo (T/v-37) ayeqdsoyg = < 8°89 Pa . . 9°19 +'09 S 7SE Z'8E 6°6£ 4 Lib PS 69 a (T/V-37) arear|ts a 5 5 0 0 0 €SZ zl z9 9'°% s‘T Z'0— LZ0L 9Z0L SZOL 46 991 99T 096] ABI ¢ LOT SEZ y LS‘T or'2 990. 3 18°% Z6°% 122 pS ee = = — 0 = (T/A) wadsxQ Zz'be sey LOVE S6°ES 91 Z8°EE Z8°EE SLEE Ly = BSCE Z9° EE IS°€£ 0 B (%) Arures 878 SEZ ~ 19°8 Z6'8 991 S £Z'0T IE‘OT Zz'01 Lb = 91 — O'LT 0 S (D.) ainjesradwa J, 0 0 0 (m1) stxe aaoqy ESZ Z8t z9 (wi) woy0g 4 ST c0— (wy) suRISIG LZ0L 9Z0L SZ0L uoneig NOANV<) LYOdMd N 47 SUBMARINE CANYONS EMERY AND HULSEMANN: No. | youerig sddtiss, 9L°0 6SE SIT ra | SEZ Is'T — L9°T StI $9°7 912 _— $S'Z 8 — — — — 0 (T/lu) wadkxQ 9L'% 6S¢ 67° bE 6S¢ sar4 $9'7 SEZ E7'bE ez'bs $£z 6£° _— 6£°2 Stl tbe — IV'bE Stl £V'Z £l'Z — $0°Z L8 86°SE Z0'bE — £6°EE 8 9£°0 87°0 940 8£°0 0 99° $9°EE 79'S 29'S 0 (I/v-87) ayeydsoyg (°%) Asrurpeg +'t8 6S¢ £S°L 6S¢ 6'SL 6°SL SEZ +18 $78 S£Z 6°19 — L'+9 Stl L6°8 — 668 8tT S'S 6'bS — 0°6+ L8 7P'6 0£°6 — 09°6 8 Al SIT 8'0T 6'01 0 8°91 sO Zor rah 0 (T/V-37) azeorIg (Oo) ainjesadwa 7, L 6 0 zZ L 6 0 Zz (WI) sIxe saoqy 69£ 0SZ £91 FAIR 696 0SZ £91 ZO (uw) woyHog a+ +1 £0 z'0 av a £0 z'0 (my) eouR STG 9602 S£0L +£0L ££0L 9£0L SEOL #bf0Z ££0L uonEIS 0961 ABT 9 NOANVZ) VTIOf[ WT] (uw) qdaq (w) widaq (wi) yidaq VOL..2/ ALLAN HANCOCK PACIFIC EXPEDITIONS 48 8°02 £02 681 9°9T Ez (T/V-87) aenIN reNNN ot NO —) mA OW Nm MK ea Sal (T/V-87) ayeotytg 0 0 £0ct 9SE 8c Vy £v89 8b89 man CONN 096[ Atenigay | 89°0 T£°0 ett 88°0 8r'? cot a 88'T =a 6S'¢ $3°S 9L°S (‘J/[w) uadhxQ bS"bE SOE 6I'vE IVE 00'rE POPE == S6°EE CIEE LL Et 6v'ee 8S°EE (9%) Arures oot cl'9 ELL 8L°L ££°6 i a c1'6 = 60°01 (D.) ainjesaduia J, 0 0 c0cl 9S¢ Sc Vv £>89 8b39 NOANV7) OGWV NOWO?) 96°CE SLEE 85°C $76 9ST OT SvT L8tT (WI) sIxe dA0qGY (wr) woyog (wy) s0URISTC] U0T}EIS (ut) yideq (ut) wideaq (mw) wdoq EMERY AND HULSEMANN: SUBMARINE CANYONS 49 NO. 6% = 61 (T/v-87) areydsoyd L6 — 97 (T/V-87) azeorts S 0 18S WHA ctr Lg L089 7089 Tes 802 Tes 80¢ OSoied esc? 82'°0 = 0L'% (T/[w) uadAxO 07'bE — BLEE (0%) Aarures 06'S = $9°6 (O.) aanyetadua 7, $ 0 18s Occ ovr Lg L089 e089 NOANVS) ZAYD VINVS TES 802 Tes 802 (tw) stxe aaoqy (Ww) wWoV}0g (wy) sDUeISIG u0neIs (wi) yrdaq (wi) widaq (uw) widaq ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 27 50 "SE ofzI 9Z°0 Of oy 1'8z $97 10Z $50 £5°0 WL os +92 6°LZ 9°bZ Lee £Z'0 £60 LOT Lee a Z'SZ bbz = 6'LI Z61 8£°Z $77 = 09°Z 761 bi 8°91 LT — SOI 88 0z'b 97> = +1" 88 3 (T/V-37) ae.nIN (T/lw) uasixQ S*¢ OfzI ZS" 4 are £"€ £"¢ 10Z Othe 67S TOL 3 Ve 62 Ve Lee ZZ'bE 7Z'bE 7Z'+E Loe be! td A — +7 Z61 26'S 00'bs — S6°SE Z61 = eT ¢ — eT 88 BSCE 8S°EE — 8S°EE 88 3 (1/v-37) ayeydsoydg (9%) Aarurpes 802 trAt 90°F oft +91 LIT 10Z UUs 65°9 104 = £8 Or 98 Lvs OSL 6S°L 09°L Lvs % 1S zs — £S Z61 726 60°6 -- 10°6 261 = 61 61 _ Zz 88 — = _ tI 88 5 _ — — a 0 OST 6'+1 8'bT ~- 0 = (T/V-37) ayearts (D0) aanjesaduiay, 06 0 0 S 06 0 0 S (UI) sIxe aAoqy Sbz1 9TL £9 902 iS TAl 91 £9€ 902 (Wi) woyo0g V9r tL 9°2 +0 V9 +L 9° +0 (wy) 20ueIsIq L789 9789 $789 $789 L789 9289 $789 $289 UOTIEIS 096I eunf gz NOANV2) VNITVLVZ VINVS No. | EMERY AND HtSLSEMANN: SUBMARINE CANYONS by | DISTANCE IN KILOMETERS NEWPORT CANYON 69, 46 = © CORONADO CANYON LA JOLLA CANYON 600 Fig. 18.—Positions and depths of water samples in six canyons at stations shown by open circles in Figures 3 through 15. The solid dots and italicized station numbers along the canyon axes indicate samples having abundant speci- mens of the polychaete worm Capitella. Cn iS) ALLAN HANCOCK PACIFIC EXPEDITIONS VOLiZ/ DISTANCE IN KILOMETERS “ Sv w Sos & & & & & ¢ () tw 2 “3 4 5 ¥'s5 7 ws 9 we 10 11 M12 13 M14 15a MeNG aS SS SS SS s——— are 12 200 200 400 a f=) i=) 2) w uw Kb Ww =200 Zz 400 ae = (600 Oo 200 400 e “MS Gf ; ve SIFICATE= ( -a/l) ; a Ag VMS a = ——_., = 10 : 200 400 600 ——— Fig. 19.—Characteristics of water in Redondo Canyon. Sym- bols same as for Figure 18. No. l EMERY AND HULSEMANN: SUBMARINE CANYONS 5) TABLE 2 CapITELLA BoTToMS IN CANYONS (from Hartman, 1962) Sample Depth Number of Canyon Number (m) Specimens* Hueneme 6897 338 1 6899 456 52 Mugu 6902 119 9 Santa Monica 6781 116 9200+ 6780 183 55 Redondo 2192 113 1 7284 137 1 3164 148 17 2148 298 P49 2190 344 133 2150 575 1 Newport 7030 85 2 5367 97 2 7730 235 7 7028 272 1 La Jolla 7043 135 595 7045 274 14145 7039 371 948 7046 517 36 7041 545 1 7040 637 3 7047 793 5 *Sampler covers an area of 0.6 square meters of ocean floor. SEDIMENTS Sampling Methods This study is based entirely upon surface samples, though cores were used in some previous work by Gorsline and Emery (1959) in a few submarine canyons. More than 90 per cent of the samples were taken with a large clam-shell bucket which covers an area of 0.6 square meter and encloses as much as 0.18 cubic meter of mud; these samples were taken primarily for the biological work to be described by Hartman. Most are the result of attempts to sample the axes of the canyons using the same procedure as that for positioning water-sampling stations. Be- cause of ship drift, however, some of the attempts missed the axes and these samples are from the steep side slopes of the canyons. About 10 per cent of the samples were obtained with a small snapper having a volume of about 500 cc. Some snapper samples are from water-sampling stations, but others are independent samples designed to learn the na- ture of sediments on the walls of the canyons. Of a total of 211 samples, 54 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 27 some kind of sediment analysis was made for 176. In 16 samples two different kinds of sediment were noted; these were separated and ana- lyzed individually. ‘Texture Textural analyses were made by a combination of standard pipette procedure for fine (< 62 micron) fractions and settling tube for the coarse fractions. Percentages of gravel, sand, silt, and clay are reported in the Appendix, along with median diameter and Trask sorting co- efficient. The Trask coefficient was used so that results would be com- parable with those of the many other analyses of sediments in the region (Emery, 1960a). A comparison of the median diameters of samples from within 10 meters of the floor of the canyons with those of samples from higher on the walls is given in the top panel of Figure 20. The frequency curves show that the sediment from the axes is only slightly coarser than that from the walls. Clean coarse, even gravelly, sediment is present in many samples from the canyon floors, but other coarse sediment occurs high on the canyon walls and atop the adjacent shelf. Fine green silty clay is common on the canyon walls but it also is interbedded with clean sands along the canyon axes. The average median diameter of the 95 axial samples is 69 microns and for the 60 wall samples it is 40 microns. A similar average median diameter of 70 microns was obtained by Cohee (1938) for 29 small dredge samples mostly from the walls of Hueneme, Mugu, Dume, Newport, and Coronado canyons. The sorting coefficients for axial and wall samples exhibit even smaller differences than do median diameters, so no distinction was made on most panels of Figure 20 for the two sources of sediments. Sorting coefficients for all canyon sediments average about 2.5 but in a general way the sorting coefficients are lower for sediments having median diam- eters coarser than 50 microns than for finer sediments: about 1.8 versus 322. No. 1 EMERY AND HtUSLSEMANN: SUBMARINE CANYONS 55 SAMPLES | NUMBER OF —_ a oO 2 eo ol OW WW [e) (©) % CALCIUM CARBONATE Fig. 20.—Relationship of median diameters of samples from submarine canyons to frequency of occurrence, sorting coefhcient, and contents of calcium carbonate and Kjel- dahl nitrogen. 56 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 27 Calcium Carbonate Dried and weighed sediment samples were treated with sulphuric acid, heated, and the evolved carbon dioxide was measured volumetrically. From these volumes the percentages of calcium carbonate were computed on the assumption that all of the carbonate was combined with calcium. The results (Fig. 20) exhibit a range from 0 to 36 per cent calcium carbonate. Nearly all values lower than 10 per cent are from canyons along the mainland. Most values higher than 10 per cent are from the offshore Santa Cruz, San Clemente, and Tanner canyons. As a secondary trend, the higher percentages for nearshore canyons occur in the finer- grained samples, and for the offshore canyons they are in the coarser- grained samples. Calcium carbonate grains coarse enough to be identified as to source organism consist dominantly of shell fragments in the coarse sediments and of foraminiferal tests in the fine sediments. Organic Matter The content of organic matter in the sediment samples was measured as nitrogen using micro-Kjeldahl equipment and as carbon using a Leco (Laboratory Equipment Company) carbon analyzer. The latter device measures the carbon dioxide evolved by fusing the sample at 1300° C in an induction furnace. Kjeldahl nitrogen would serve as an excellent measure of total organic matter except that nitrogen constitutes only about 6 per cent of total organic matter and it is more subject to oxida- tion than is carbon, as indicated by an increase of C/N ratio with depth of sediment burial or lapsed time (Emery, 1960a). Carbon comprises about 55 per cent of total organic matter but it is very difficult to measure satisfactorily, owing to the difficulty of combusting some car- bonaceous materials and to the variable ease by which carbon is released from calcium carbonate. As a result, organic carbon in samples was measured in two different ways: by combusting the residue left from carbonate analysis (direct method), and by combusting a total sample and subtracting carbonate carbon (difference method). The direct method may yield results that are too low owing to partial breakdown of or- ganic matter by the acid treatment for carbonate, or too high because of incomplete breakdown of carbonate carbon by the acid. The second method can yield erratic results because of the need for two separate subsamples. In general, the results by the two methods of carbon analysis agree (Fig. 21), but there are some individual variations and the direct method is considered the more reliable. A plot of direct organic carbon against Kjeldahl nitrogen (Fig. 22) reveals good agreement for about 95 per No. 1 EMERY AND HULSEMANN: SUBMARINE CANYONS 57 cent of the samples. A best-fit straight line through the plotted values for these samples yields an average C/N ratio of 8.9, nearly the same as the average for the surface sediments of the basins (Emery, 1960a, p. 2/6). When plotted against median diameter, the nitrogen (Fig. 20) as well as the organic carbon exhibits a close relationship. Percentages of nitrogen decrease from an average of about 0.4 per cent for sediments of 5 microns median diameter to less than 0.05 per cent for sediments of median diameter coarser than 100 microns. This relationship to grain size is typical and it results from the similarity in settling velocity of organic matter and of fine-grained silts or clays and from adsorption of organic matter on clay minerals. Average total organic matter is 2.16 per cent when computed from organic carbon (1.7 times the average of 1.27 per cent organic carbon) and 1.87 per cent when computed from nitrogen (17 times the average of 0.11 per cent nitrogen). Perhaps the best figure for average total organic matter is the average of the two values, or 2.0 per cent. Comparison with Sediments of Adjacent Areas Sediments of the canyons reveal differences which depend upon the degree of isolation from sources of detrital material. These differences are best illustrated by a comparison of sediments from canyons cutting the mainland shelf, the island shelves, and the bank tops (Table 3). Most pronounced is an increase in average percentage of calcium car- bonate from mainland canyons to island canyons to bank canyons. The average median diameter exhibits little change, except for an increase in Tanner Canyon, the only one off a bank. Percentage of organic matter increases from mainland to island canyons probably because the slower rate of deposition of similar average grain sizes of detrital sediment in the latter permits less dilution of organic matter. When compared with sediments of the source areas (mainland shelf, island shelves, and bank tops) and with those of the sites of final deposi- tion (basin floors), the sediments of the canyons are found to be inter- mediate in nearly all the averages (Table 3). Sediments of the canyons are finer grained than those of the shelves and coarser than those of the basin floors. Sorting coefficients are also intermediate, except at Tanner Canyon where only six samples are available, most of which are coarse grained. The average content of calcium carbonate also is intermediate between values for shelf and basin sediments except for the mainland canyons, which have a very low content for some unknown reason. Aver- age contents of organic matter are intermediate in all instances. These 58 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 27 4.0 CARBON direct CARBON differ. ° =~ 0.90 % ORGANIC CARBON (difference) 1.0 3.0 = ao 2.0 % ORGANIC CARBON (direct) Fig. 21—Results of separate determinations for organic car- bon on sub-samples, based on (1) analysis for carbon in residue from carbonate analysis, and (2) on analysis for total carbon minus carbonate carbon. generally intermediate characteristics of the sediments in canyons with respect to sediments of shelves and basins are reasonable in view of other lines of evidence which indicate that the canyons serve as the routes through which at least the coarser sediments reach the basins for per- manent deposition. However, the averages of Table 3 do not reveal whether the movement through the canyons is chiefly by rapid turbidity currents or by slow creep. No. 1 EMERY AND HULSEMANN: SUBMARINE CANYONS 59 0.4 CARBON __ NITROGEN FL, uJ © oO a -_ a 0.2 a 00dCti‘CtC 0.1 0.0 0.0 3.0 1.0 20 % ORGANIC CARBON (direct) Fig. 22.—Comparison of carbon and nitrogen analyses on samples from submarine canyons. VOL. 27 ALLAN HANCOCK PACIFIC EXPEDITIONS 60 ‘asreoo A[]euOIZdaox9a—uO0AURD ZNID BIULG WOIF 6089 UOT}EIs BuIIWO , ‘uado1yIU YX LT PUB UOgIeD d1UeSIO YX Z*] Jo AdeIDAR — SUOAULD JOF 19}}2U DTULTIOg ‘sajdwies jo Jaquinu st sasayjuaied ur 1aqUINNg ‘IWEN ON ‘Sa}IOD yseq ‘se[OOINY ues, *IJUUL Tg ‘ayUIWI[D) URS ‘eUT[R}eD BULBS ‘ZNID BUCS, ‘aJUIUII[D URS ‘BUI[L}JeD BUG ‘zNID BJU, ‘oSaIq{ uvg ‘O1pag uRG ‘BoTUO;] BURG ‘eIEqIEg BURG, ‘Opeuolog ‘eljof ey G1odman ‘opuopay ‘eotuoyy Bjueg ‘suing ‘nsnypy ‘auauanyy{z "(072 ‘18t ‘dd ‘eg961) Arawy wo1y eyep uokuRd-UONT (8) +9 (8) 8£°0 — (99) SIZ (8b) TE (0S) O° ,SuIseg a104sy¥O (9) v2 (9) L0°0 (9) 60°2 (9) LEZ (9) 6'T (9) 86 gsuokuey yueg (9tT) 8°0 _ — (991) 9g (v9T) £2 ($82) 042 sdoy, yueg (€Z) 92 (€Z) Sv'0 —_ (6£1) O'ZT (€IT) 8°€ (LIT) O'F gSUISEG I1OYSHO B3e1IPOY] (32) eC (82) +10 (82) SLT (92) €°2I (0Z) o°€ or(61) 29 pSuokue) puelsy (891) 9°0 _— — (95%) L2 (062) ZT (862) 092 Saajayg pues] (6£) £°9 (6£) L£°0 — (ZET) £01 (O81) L'¢ (9ZE) $°9 eSUISeg A104sIvIN] (€£T) 661 (£1) ITO (811) IVT (SET) 8°€ (€b1) v2 (tbl) $9 gsuoduey) puejureyy (€£Z) 6°0 — = (16S) 26 (+08) 9°T s(€LZT) O€t F12YS puelure yy (%) (%) (%) (%) (4881.1) (7) Ne (14yep]9!st) O s1ued19 008) WUIIIYIo) =“ BI._: UR Tpayy d1ULsIO uas0DIN BUNIOS pSLNAWNOWANY YWHLE GNV SNOANVZ) AINTYVWANS AO SLNAWIGES € WIaVL NO. 1 EMERY AND HULSEMANN: SUBMARINE CANYONS 61 SUMMARY AND CONCLUSIONS In many ways submarine canyons are intermediate between shelves and basin floors. Their axial slopes are intermediate in steepness; thus the canyons not only dissect the basin slopes but their heads extend landward of the shelf break. Where the heads of the canyons are very close to shore they may serve as local sites for upwelling in response to the action of wind in driving surface water toward the open sea. This upwelling, however, appears to be weak and probably discontinuous. It does not establish a very unique ecological environment, but the minor differences in the waters of canyons or basins which do exist may pos- sibly be significant for some animals. Canyons which cross much of the width of shelves and of basin slopes receive sediments in at least three different ways. Most important quantitatively is grain-by-grain deposition of silts and clays carried in suspension from the mouths of streams and from the turbulent shore zone. When deposited, this sediment forms a homogeneous blanket of green mud on the steep walls of the canyons as well as on the basin slopes and floors farther seaward. The steepness of the canyon walls, possibly aided by animal activities, allows the sediment to move down- slope to the canyon axes. This movement not only exposes rock outcrops on the sides of the canyons but also produces interbeds of the green mud with coarser sediment on the canyon floors. Whether the mud moves downslope slowly and continuously or rapidly and intermittently is unknown. The outer parts of the canyons, the channels on the basin floors, also receive the grain-by-grain deposits, but because of the gentle slopes of the sub-sea aprons there probably is little mass movement of this sediment. Second most important, but probably of greatest interest, is the depo- sition of sand and fine gravels which move down coast along beaches and atop the inner part of the shelves, under the influence of longshore currents. These currents are partly the inshore portions of the general southern California eddy but mostly they are produced by the diagonal approach to shore of the dominant waves from the northwest (Emery, 1960a). Where canyons extend close in to shore, they serve as traps for this moving sediment. The sediment may accumulate slowly until it finally moves out en mass, causing a sudden deepening of the water of the canyon head (Shepard, 1951a, and other papers). The moving mass may become transformed into a turbidity current which carries sand into deep water (Shepard, 1951b), building up sub-sea fans or aprons at the mouths of the canyons (Gorsline and Emery, 1959; Emery, 1960b). These sands have the same general grain size as the nearshore sediments 62 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 27 of the shelves and they contain shallow-water foraminifera and remains of other animals and plants, including bits of wood from land. Within the canyons the sands form narrow bands traversing the canyon axes between the steep walls covered by green mud. Movement of this mud downslope to the intermittently moving axial sand produces the observed bedded character of the sediment on the floors of the canyons. The sands in canyons near the mainland contain lower percentages of calcium car- bonate than do the muds, in agreement with the low content of calcium carbonate in sands atop the mainland shelves as compared with that of muds on the basin slopes and floors. In contrast, the sands in offshore canyons have more calcium carbonate than the muds, again in response to the shelly nature of sands of island shelves and bank tops. Third, and least important, are small quantities of sediment from the outer parts of the shelves which are moved into the canyons, probably by occasional storm waves. Their presence is attested by occasional grains of glauconite and phosphorite, authigenic sediments which are most com- mon on bank tops and on the outer parts of shelves. As shown by Menard (1955) and by Emery (1960a), the quantities of sediment in sub-sea fans and aprons far exceed the volume of rock which has been removed during erosion of the canyons. Since the fans consist mostly of sand, it is evident that the canyons act as conduits for movement of sand from near shore to deep water. As pointed out by others, this movement may act as a sort of giant chain saw cutting down- ward into the bedrock floors of the canyons. Deepening of the axes steepens the side walls and allows more sliding of muds from the canyon walls, possibly leading to lateral enlargement of the canyons. Future work from manned or televised deep-diving vehicles should go far toward investigating this interesting geological agent of erosion. Downcutting of canyon axes by moving axial sands should clear away a strip through the blanketing muds or prevent the muds from being deposited. Any aquifer which has been exposed through erosion by the same sand or by other possible canyon-forming agents is thereby exposed to the sea water. If the internal water pressure is greater than hydro- static pressure of sea water at the outcrop, fresh water should leak to the sea. If the reverse is true, owing to over-pumping or perhaps to natural causes, sea-water intrusion should occur. Because of widespread over-pumping in the intensely cultivated and highly populated coastal areas of southern California, sea-water intrusion is well known. It is generally made manifest by increasing salinity of water wells (Emery, 1960a). Deeper aquifers, largely untapped by water wells, may be expected to behave differently than the over-pumped shallow ones. No. 1 EMERY AND HULSEMANN: SUBMARINE CANYONS 63 Accordingly, it should occasion no great surprise to learn that the deep aquifers still discharge fresh water, as did the shallow ones during the nineteenth century. The quantity of discharge must be small compared with the volume of sea water within the canyons. Accordingly, one should not expect to detect it through water analyses, except perhaps of interstitial waters of axial sands or by visual inspection from deep- diving vehicles. The finding of fresh-water worms and the absence of marine animals in more than a score of axial sediment samples serves as a clear indication of seaward loss of water from deep aquifers. Prob- ably most of the loss of fresh water from these aquifers occurs through the canyons because they represent the points of outcrop of aquifers nearest land and thus are the focal points of the steepest pressure gradients. 64 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.27 LITERATURE CITED BENEST, H. 1899. Submarine gullies, river outlets, and fresh-water escapes beneath the sea-level. Geogr. Jour., 14:394-413. BuFFINGTON, E. C. 1951. Gullied submarine slopes off southern California (Abstr.). Geol. Soc. America, Bull., 62:1497. 1952. Submarine “natural levees.” Jour. Geol., 60 :473-479. in press. Geophysical evidence on the origin of gullied submarine slopes, San Clemente, California. Jour. Geol. CoHEE, G. V. 1938. Sediments of the submarine canyons off the California coast. Jour. Sedi- ment. Petrol., 8:19-33. Emery, K. O. 1954. Source of water in basins off southern California. Jour. Mar. Res., 1331-21. 1960a. The sea off southern California: a modern habitat of petroleum. 366p. Wiley, New York. 1960b. Basin plains and aprons off southern California. Jour. Geol., 68 :464- 479. Emery, K. O., AND F. P. SHEPARD 1945. Lithology of the sea floor off southern California. Geol. Soc. America, Bull., 56:431-477. Emery, K.O., anp R. D. TERRY 1956. A submarine slope of southern California. Jour. Geol., 64:271-280. GorsLinE, D. S., AND K. O. EMERY 1959. Turbidity-current deposits in San Pedro and Santa Monica basins off southern California. Geol. Soc. America, Bull., 70:270-290. HARTMAN, OLGA 1962. A new monstrillid copepod parasitic in capitellid polychaetes in south- ern California. Zool. Anz., 167 :325-334. Jounson, D. W. 1938-39. Origin of submarine canyons. Jour. Geomorphol., 1:111-129, 230-243, 324-340; 2:42-60, 133-158, 213-236. LuskIN, B., B. C. HEEZEN, M. Ew1nc, AND M. LANDISMAN 1954. Precision measurement of ocean depth. Deep-sea Res., 1:131-140. MeEnarp, H. W. 1955. Deep-sea channels, topography, and sedimentation. Amer. Assoc. Petrol. Geologists, Bull., 39:236-255. NorTHROP, JOHN 1953. A bathymetric profile across the Hudson Submarine Canyon and its tributaries. Jour. Mar. Res., 12 :223-232. RITTENBERG, S. C., K. O. Emery, AND W. L. Orr 1955. Regeneration of nutrients in sediments of marine basins. Deep-sea Res., 3 :23-45. SHEPARD, F. P. 1951a. Mass movements in submarine canyon heads. Amer. Geophys. Union, Trans., 32:405-418. 1951b. Transportation of sand into deep water. Soc. Econ. Paleontologists and Mineralogists, Spec. Pub., 2:53-64. SHEPARD, F. P., AND C. N. BEARD 1938. Submarine canyons: Distribution and longitudinal profiles. Geogr. Rev., 28 :439-451. SHEPARD, F. P., AND K. O. EMERY 1941. Submarine topography off the California coast: Canyons and tectonic interpretations. Geol. Soc. America, Spec. Pap. 31, 171p. SHEPARD, F. P., R. REVELLE, AND R. S. DiETz 1939. Ocean bottom currents off the California coast. Science, 89 :488-489. APPENDICES TO" VOL.2/ ALLAN HANCOCK PACIFIC EXPEDITIONS NX = % (14yeplal st) N 80° a st 0 LV oa tT c +9" $2 $°% 61 be" or VST c £8 £"€ 9° 12 0¢ oT st + ov 0c oc? el 9L° 0g 97 c2 vY Lt 9? 4 cl os L’s oC o'r @ Uy ce 82 % Laser] (3941p) 9%, yUWaToYya0o (My >) (1-29) OD wurdIQ*%DjeD Buns0og AkeIDQ% yig % tI cL pues /[aavis = 76/9¢y. 98 OTT" 0 86 06 vst" c 1c9 IT cc0" IT tly #oS/9E Sol 6 9Sb s) 810° 9 elt $9 $60° 6 SEE Sb 1s0° 91 Ile IT 610° 0 6fb 0 est 0 tLe | c£0'0 0 9LE L SLT 0 eLe 68 8cr" 02 Sor 6 T£0° 0 60£ [vau | [uw] [wu] ("79<) JajJaWeRIp sixeaAoqe yideq PUES Zo. MErpelN YSIIH u00,€T u00,ST u8C,b1 u8C,bl uSS,E1 ubt,tl ubt,£T ubb,vt u8t,£T wOl,vT wOT,bT uS TET uOT,bt u0C,£1 uSb,ETo6ET ‘SUOT u0£,80 «00,10 «90,£0 uSS,£0 «00,50 ut1,90 u8t,L0 uSS,£0 «00,80 uS€,50 u$C,S0 «00,80 u0£,S0 100,80 uST,LOové yey] $069 1069 0069 6689 8689 £689 9689 189 889S 9895 cess Tess STIS bits 9484 ‘ON ajduieg 66 NOANV‘) AWaINAN 67 EMERY AND HULSEMANN: SUBMARINE CANYONS NO. 1 0 0S8 wS7,6So8TT «w9T,LS TZSZ co $6'T aS at St £9 c 800° 0 c6L ubt,10 u0£,8S £169 +0’ bY’ 4 st 8 LS Sé 1S0° 0 1cZ u£Z,t0 u07,6S o£ c169 c0" te st oar 9 tf 19 cL0° 0 br9 uS&,S0 «00,10 1169 90° cs" $s’? Le 0c $9 ST $20 S€ 8bs «$0,$0 u£1,c0 0169 90° £8 ‘2 et 9¢ co L/S +10" Ofc cSt w0£,c0 u0S,10 6069 0 8T° tT st 0 T £6/9 Str’ 0 LOE ul,90 uch +0 £069 T0° L£9° 4 ot T v 68/9 89C° 0 SLb we1,$0 uSb,£0 +069 $0° be" a4 Lv 9¢ 6¢ St 620° 0 cst ucl,90 ucb,b0 £069 c0" 90° 6'T Ty 9 cl £5/62 986'T 0 6IT u&Z,S0 «02,0 c069 10° 3'T a € £ +6 OTT sot ST uSt,50 ut1,50 cS8t 80° £'¢ | 91 tb I c+0" SCE TLT uSS,S0.6TE wOl,f0.Ff IS8t % % [yses.1.] [wu] [uw] [ut] ‘Bu0T wT ‘ON (Tyeplafszy) (3991p) % yuarysos (p>) (My-z9) (NZ9<) JDJOWeIP sIxeaaoqe yidaq ajduies N = QouesiQ Hey Bunsog APD % ylS% purgy% uerpayw I3943PH NOANV7) Noa VOL. 27 ALLAN HANCOCK PACIFIC EXPEDITIONS 68 (1yeppfs) N L3'T (a011p) 0'r oy Ve 6'T 67 %, Ve 62 19 or Z10° O's lz z9 I £10" s" 44 6S 61 ZZ0" ge LI zl I +10" eT L +1 6L 780° [yseay | [uru | yuarayyaoa (p>) (I-79) (1279<) AajaWIeIp DouesiQ ORD Bunsg ArjQ% IIS % pues % ueipaw NOANVD JNNG [uw] stxe dAOge Ysa 08s ItZ TIZ OES 662 9S c$9 L0S ble 86£ [ur] wrdaq u9 £80 «8,05 100,64 uSb8b u0b,8b uS€,8P uS 1,60 uLT,8¥ uS1,8¥ uS E80 ulT VS o8TT ‘SUOT u8T,Ls uSE,9S uol LS uOE,8S uST,6S u0S,L uce,L$ ult 8S uS 1,68 uOT,6S ubE,VS of wT OcsZ 8169 L169 9169 S169 $689 9L9S bL9S $0ss 9+05 $962 ‘ON ajduies 69 EMERY AND HULSEMANN: SUBMARINE CANYONS No. l LV bs'T Or 90° $6° ve 80° 89° 8°C 80° 89° ve or 86° vt ce $8°C o8 or 97°E 6°8 8°Cl %N % (1yeppfy) (oe1p) =% 4 LI 8h S€ Tt0° 0 bSt «00,6 u8T,S$ £829 ob I ST OL/+t ££ 0 9TT ucS CE u8S,SS 1829 ce 9 <4 OL cor’ 0 £81 u07, EE uLb,SS 0829 4 6 8c £9 Scr 0 SLY uk BE u62,SS 6LL9 9? st tr Iv $r0° ST £8S a$$ ,1¥ u£S,€S 8LL9 Oe 8£ 19 I £00° 0 OT8 uO CF uSC,1S LLLY 8° 8€ 6S £ 900° 0 £28 u0C, 1b u0E,8h 9LL9 eT at EL tI cr" 061 £9v uST,6€ u80,CS 66£E 9? cl Ts LE £+0° 0 O£E uSS,SE u0E,SS O8TE aa 61 19 02 8£0° 0s c9€ 100,8 u6E,SS 6LTE Ve cz 89 OT O10 OL Tet u8t,6£ u8E 0S 8LTE ce Le L9 9 910° O£ crs u9€ Th u9T,ES LLYE ve 97 cL c 600° 0€ cg wLS,tb «8S 1S 9LTE cel 892 uO ,LE u1,SS 000E ve 8T 89 tI $£0° Sor tsb u00,0P.8TT «TT, ES o£ 6667 [aseay] [wu] [w] [uw] Buoy Wy] ON wUaTIys0I (Mh >) (Mt-7Z9) (1Z9<) Ad}aWILIP sIxeaaoqe yYydaq ajdures N O URSIQ ORD Bupsog ALI % IS % purg % uvipayy IYSIOH SSSSS70°0=wwOOSoj]]+ oqo SS 000 NOANVZ) VOINOJ{, VINVS ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.Z27 70 nies £8 u10,Cf u00,0% AAV uBy 8+8 ut0,08 «00,0% Octe Wi 808 u£0,9C 100,c0 61b2 We 9+8 100,82 u8S,1¥ S0bc Wey O18 100,82 u8S,1¥ b0re ues 1574 100,82 u80,tb £0b~ uefy b6L «90,0 uSS,1b £9EC 6'T 0c 09 4 TE0° uey cs9 uS VE 100,90 CIES 0° cl Ob 8b 090° adojs urseq Ore uL0,0€ u£0,LY T9ES aA LS u£0,9¢ 100,8F 6S EF £S8 u£0,9C u00,0¥ CCLC Sf ell 07 ,b7 18S 6% Z61Z L Cte u8T,SC ucv,6¥ T6lé Or bre u8£,9C ub T,60 0612 0 cob u0E,82 ubE 8b 6812 09 cbs u6£,0€ 190,80 TSt¢ Of SLS u9 FTE u9S LY OST? 0 6£¢ uLE,SE uv$ 60 6b1? 0 86¢ utS,SC uch 60 8tIZ Wee 108 u8F,E£o8EE w8C,Tbobf 6£12 %y % Cysear] [wun] [us] [uw] ‘BUT wT ‘ON (qyeppafsy) (49241p) % yuarsya0d (p>) (74-29) (Izg9<) JajaueIp sixeaaoqe yidaqt ajduirs N Q o1ue1Q 09k Bunsog ALIN % WIS % pues % ueipyw I3WsPH 3/22 92 ™O™09Sasvw_axnm_axrvwwjj\e = _ll””—wwww—oo— NOANV7) OGNOGd SUBMARINE CANYONS TA EMERY AND HULSEMANN No. l a SS 6% or Ee TT 8°Z 8 oc 82 Lb id 0'€ zz tb 8°2 81 Sb s‘T 8 a4 LI % % [yseay | (yePlafsy) (aeqp) —% =~ uatouya0o (p>) N = Qoruesdig *ON2D Sunsog Ar] % 0s 9S 9S OL cb $9 $s 8S tS Sv 6L Lv b [aAvid pue yo01 (I+-Z9 ) WIS % (z9<) qayaureIp pues % £+0° 620° 6£0° 900° 8£0° £20° L00° £20" $00° 850° 970° [usu] ueIpay Or S 0 LS uej scl adojs urseq uey adojs urseq adoyjs urseq urj Ofb OLE 00£ uvj uej ury uey uey ues [uw] stxe aaoge yjydaq ysPH 61S £9E Stl TIT 96L S9b 9S$ 69L bee Lot $8 ect oft LOT c09 bLL 008 STL 989 TsZ [wi] u8€,6C ubT,Le ult te uk ve 100,9€ «00,c£ u6$,£E u£0,9€ u00,9€ uS0,E u0S,SE u00,C£ «00,0 100,82 u00,0€ 16S ££ ut0,c£ 16S 62 u£0,c& u80,bE 8TT “Su0T uI T 8b uST,60 ucS 60 u&S 60 uc0,tb 100,8¢ u6S,LY 100,8¢ 18S ,6¥ u6S,6¥ u6S,S¥ 1 00,0 100,08 «00,08 100,9¢ uc0,vb uc0,cV u00,+¢ uc0,bb ul0,9bo8E Wey Ne eee (penurjuo7) NOANV7) OGNOdAY VOL. 27 ALLAN HANCOCK PACIFIC EXPEDITIONS 80° +6 os oC 91 6S SZ 9£0° 0 119 u8S 9 uS€,LE 06cL br eel ov ee 61 Lv ve 9£0° a a: u0S 0 uV1,8P 68¢L c0° 90° ore “LT T + $6 £s¢° 0 09s u0S ,0€ ut 18d 68cL $0° Ls" VC tT L At 9L 880° a i: uV1 60 u67,8d 882L 60° 86° Ve 6°C tr 9€ 0s 290° 0 £0 uvT 67 u62,80 88cL st Ts'T oe oe 02 Ts 62 620° ut u£S LO uS¥,8b L8cL cv Ort 8°¢ oe Lt Sv 8E 8£0° 0 lev u£$ Le uSt,80 L8cL 91° crt 0'r ss oT fv Tv £0° t uv5 9S uCC,6¥ 98CL tr Oc'T 6'€ ft st Sv OF +b0° Z i uv$ 9S ucC,60 98cL cl col fe a4 cl te £s$ c90° 0 BLE uv ,97 ucC,6¥ 98CL $c Ive sv Ove 1! 08 $ st0° 0 Ibe u8b SC uC 6 S8cL 6 68'T cv ve LT 99 LI T£0° 0 Let ul fe u£S 6 scl L0° BL LST ve fc 8$ 61 610° aie4s 9L ub 8C u9S LY L189 0c" 96'T os ST IT £S 9¢ Ts0° 8 SLE u¥0,LE u€1,6¥ 9189 60° amt Ls Ve 14 $$ <4 £20 98 c82 uv5 9S ud1,6¥ ST89 8o° IVS 69 ee St £9 c 600° UBy 98L uST,VE uct IV SLL9 st 89°T LY ve 82 £9 6 STO" uey 099 u0S,C£ uv0,LY vLL9 £0° “it vl S fe c9 cL0 00v al u0S,£E u8T,0S 096S 8°02 eT 8 SZ LI c+0° Oth Ocl u£C,CE 100,08 S8EE a4 ST 18 v £10° uy 90L ucv, EE ut £9 69TE XC cl £$ St £0" St bss uOL,CEo8TE =n OV,LHEE 89TE % %s [ysvaz] [wu] [w]) [wi] ‘Bu0T Wy “ON ({qepjefsy) (39e.11p) % yuatoysos (Wp>) (Mp-79) (1Z9<) AgjJoWIeIp sxe aaoqe y3daq ajdueg N = QotuediQ *ODR2D Sunsog ALI % HIS % purg% uerpay IwsrHy (panunuod) NOANW.) 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