VOL. IX. NO. 4 JUNE 1963

EDITOR: JAN HAHN

Published quarterly and distributed to the Associates,
to Marine libraries and universities around the world,
to other educational institutions, to major city public
libraries and to other organizations and publications.

HENRY B. BIGELOW

Founder Chairman

NOEL B. MCLEAN

Chairman, Board of Trustee}

PAUL M. FYE

President and Director

COLUMBUS O'D ISELIN

H. B. Bige/oiv Oceanographer

BOSTWICK H. KETCHUM

Associate Director of Biolo&\ and Chemistry

Library of Congress Catalogue Card Number: 59-34518

X

The Woods Hole Oceanographic Institution • Woods Hole, Massachusetts

E

VOL. IX, No. 4, June 1963

Buoy

Retrieved

VEN in a calm sea quiet a bit of stretching and muscle exercise are
involved in retrieving the current meters which are suspended below the
buoys of our anchored stations.

A successful program of moored buoys was carried out as part of our
work for "Operation Equalant I".

Editorial

VOL. IX, No. 4, June 1963

.FREQUENTLY, one reads questions about international co-operation in
science, particularly in the case of space research. The answers given
usually are vague and tied closely to politics. It is not sufficiently well
known that in oceanography there is thriving agreement among many
nations, including the USSR.

In the International Indian Ocean Expedition some 40 ships of 25
nations are taking part. The example of the IGY only is a few years
behind us. This spring, two of our ships, the R/V 'Chain' and the R/V
'Crawford' took part in "Operation Equalant I", an intensive investigation
of the Atlantic Equatorial region. Thirteen ships from seven nations were
involved in this study. Four came from the U.S., three from the USSR,
two from Brazil, one from Argentina and one each from Nigeria, the
Republic of the Ivory Coast, and the Republic of Congo-Brazaville. In
addition people from various nations mingled on other ships. Texans,
Floridians and Californians were on the South American ships, while the
'Chain' also had scientists on board from Great Britain, Venezuela, Brazil,
West Germany and visitors from four other U.S. laboratories.

Not the least interesting part of the work done by the 'Chain' was a
landing on St. Peter and St. Paul Rocks (see page 2). These desolate bits
of rock pinnacle just above the sea surface in the middle of the deep ocean
and must have struck terror in the hearts of those sailing ships who may
have suddenly come upon this boiling cauldron in the middle of the night.
The rocks are so uninviting that a second landing a month later was not
possible although the weather was only moderately rough. The landing
was made partly as a reconnaissance survey to determine if the U.S.
MOHOLE project could land supplies to drill through the outer crust of
the earth, an attempt which previously has been tried from a drilling
barge in the Pacific.

The articles in this issue provide only a glimpse of the work done on
board our ships: we cannot duplicate the heat in our quarters, the fragrant
and not so fragrant smells of some of the ports visited, nor the admiration
we felt for the two Brazilian divers who, for five days, worked in unbeliev-
ably murky water at 86°F., to repair the damaged propeller blades of the
'Chain' with a small hacksaw. (No docking facilities were available.)

We also wish to thank our (unpaid) contributors who were hounded by
the editor to sit down in the 110° temperatures on board ship to write
their articles before the}' scattered home. A rather large number of paper
towels were used under their wrists to prevent the writing paper from
disintegrating. Thanks also are due to the officers and crews, and particu-
larly to the stewards and cooks who provided excellent and frequent meals.

A Visit

to

St. Peter and St. Paul Rocks

by P. L. SACHS

Would these desolate rocks in the middle of the ocean
provide a stable platform for Mohole drilling?

o

'N March 18, 1963, a party of four
geologists from the research vessel
'Chain' landed on the largest islet of
St. Peter and St. Paul Rocks. The
desolate appearance of this jagged
group of pinnacles belies their popu-
larity with inquisitive minds, and the
four were following in the footsteps
of distinguished visitors, including
Darwin, who had arrived here in
such famous ships as the Beagle, the
Challenger, the Meteor and the
Albatross.

The rocks were discovered some-
time in the first half of the sixteenth
century and first appear on Mercator's
Chart of 1538. They are located nearly
on the equator at 00° 56' N, 20°22' W,
about 500 miles from the South
American coast and roughly twice that
distance from the African coast. The
group consists of five islets, the larg-
est measuring less than 400 by 200
feet, four small rocks and a few
pinnacles barely above the surface.
Two of the islets reach a height of

MM*

"-

The Rochedos Sao Pedro e Sao Paulo, commonly known as St. Paul Rocks, belong to
Brazil. They are a parf of the Mid-Atlantic Ridge sticking above the sea surface.
Boiling surf obscures the shore line configuration of these desolate islets in the

middle of the ocean.

about 40 feet. A swell nearly always
surges around the rocks and rips
indicate the westerly flow of the
Equatorial Current. An untended
lighthouse was erected on the largest
of the islets by the Brazilian govern-
ment in 1930-31. It was operative for
only a few months however, and now
only a skeletal ruin remains. Nearly
tame sea birds, a great number of

land crabs and numerous species of
fish and porpoises constitute the
dominant fauna of the group, but
sharks which figured more or less
prominently in most of the earlier
reports were observed only well off-
shore.

To the geologist, St. Peter and St.
Paul Rocks are a fascinating and
exciting feature, of considerable

St. Paul Rocks

scientific interest for a number of
reasons. Not only are they one of the
few places where the great mid-
Atlantic Ridge rises above the surface,
but they are nearly unique among
oceanic island in composition. Prac-
tically all other islands consist of
extrusive volcanic material often
covered by calcareous sedimentary
rock. St. Paul Rocks, on the other
hand, are composed largely of perido-
tite, an ultra-basic igneous rock, rich
in olivine, generally formed only at
considerable depths below the
earth's surface. This material is be-
lieved by many to constitute the
mantle below the Mohorovicic dis-
continuity, and its appearance at the
surface in relatively fresh, unaltered
condition, leads to some interesting
speculation. The rocks may have
been carried up from great depths
through the crust by rising convec-
tion currents in the mantle. This
mechanism has been postulated by
some for the formation of the Mid-
Atlantic Ridge. The very considerable
seismic activity of the area, the
topographic expression of the Ridge
in this region and the nature of the
alteration and deformation of some
of the rocks, all suggest faulting on
a grand scale, which may have
squeezed abyssal material to the sur-
face. These hypotheses for the origin
of St. Paul Rocks are not mutually
exclusive, and it seems plausible that
both processes may have been opera-
tive.

Extensive analyses of rock samples
from this location should yield much
new information concerning the islets,

BASALTIC LAVAS
AND PYROCLASTICS

SEA LEVEL

60 KM

GABBROIC
INTRUSION

\ CRUST
PERIOOTITEX
MOHOROVICIC

RISING
MAGMA

Mr. SACHS is a geologist in our
Department of Chemistry and Geology,
with Dr. V. T. Bowen.

but previous landing parties had
never collected sufficient material for
some of this work. It was primarily
for this reason that a landing here,
as part of the 'Chain's' Equalant Pro-
gram was considered most desirable.

Objectives

More specifically the landing party
had four objectives: 1. A large
amount of as many igneous rock
varieties as could be found was to be
collected for various chemical and
petrological analyses, and subsequent
correlation and comparison with off-
shore samples. 2. Sedimentary de-
posits formed by the reaction of
guano with weathered igneous ma-
terial and carbonates present, were
to be sampled preferably in all stages
of the process. 3. Oriented rock speci-
mens for petrofabric analyses which
might yield clues about the directions
of forces which have deformed the
rocks were to be obtained. 4. A
reconnaissance survey was to be
made to determine the feasibility of
putting a drill rig ashore later this
year.

As 'Chain' approached the area, the
group of jagged stark pinnacles ap-
peared out of the morning mist low
on the horizon to fire the imagination
of those who stood lining the rail.
The ship approached to within 1000
yards and launched a boat and a
raft containing the landing party
with their gear. The launch took the
raft in tow and circled the rocks so
that a landing site might be chosen.

'RISING CONVECTION
CURRENTS

Sf. Paul Rocks may have been carried up
through the crust of the earth by rising con-
vection currents in the earth's mantle.

(After Hess, 1954. Courtesy: U.S. Naval Oceano-
graphic Office)

The famed 'Challenger' tied
to the St. Paul Rocks on
August 27, 1873, not an easy
task for a square rigged ship.
The 'Chain', on March 18,
1963 stayed 1,000 yards off-
shore. In both cases the actual
landings were made by
small boats.

This composite view of the
ships was made at the sug-
gestion of our Port Captain
J. Pike. The original engrav-
ing is from: Sir C. Wyville
Thompson: "Voyage of the
Challenger", Harper Bros.,
1878.

H.M.S. Challenger, 1873

R.V. Chain, 1963

Difficult landing

The charts state: "difficult landing",
and indeed on this occasion there was
no question of actually landing any
craft. The swell surging through a
cove which had been the site of most
previous landings made any attempt
at entering appear hazardous. There
seemed to be only two small areas
where boiling surf did not continu-
ously surround the rocks. A small
ledge above one of these, on the
western side of the Southwest Islet
looked most promising and the raft
was maneuvered close to this spot.
One by one, the members of the land-
ing party chose what seemed the
propitious instant, and each in turn
leaped for the ledge when the raft
was carried upward and close to the
rocks by the surging swell. Gear and
food were thrown ashore by those
remaining in the raft and launch,
after which they returned to the
'Chain' to proceed with her assign-
ments of bathymetry and rock dredg-
ing while the landing party went to
work on the islet.

Once ashore there was little to
modify the original impression of
desolation. The sun was by then
directly overhead and no place on
the Rocks afforded any shelter. There
was a pervading odor of guano and
the birds, some with young or
brooding, screamed at the intruders.
Not a trace of vegetation graced the
rocks, and the only refreshing aspects
were the clarity of the surrounding
waters, and some small salt water
pools which sheltered a number of
colorful reef fish and were frequently
replenished by spray and surge.

Rocks collected

After a brief reconnaissance which
included the derelict lighthouse and
divulged some letters and photos left
in a sealed jug by previous visitors,*
the party began to chip, sledge and
blast off rock samples, until the
launch returned for them in the after-
noon. The collection of hundreds of
pounds of samples from the South-
west Islet, as well as rewarding
dredge hauls from surrounding
waters, successfully concluded the
field work for the investigations, and
should, when analyses are completed,
substantially increase present knowl-
edge about the geology of St. Peter
and St. Paul Rocks.

*The 'Chain' left a canvas flag on which had
been painted the date of the visit and the
names of all those on board ship.

?%£?.

' <** -te^^^^a."

21 *» & ?C - 3B » « 7t

«> " =• ^ 2 ^S <fc \" - /

^j^r%^

y.'"1-1 **«'",

' - &TX:

is !7/! - ;9 itVU XM

« 6i IZ ,

17 13 l5

\rima

\

Mt Tamanstxij;!,

/009M:

^12 13

VA '6

T\ °'

ftl <-« >A.e

\ 9 ' 12 '<•

CUlfOF PAR/A S>^TRI,N,DAK

12 14 I6

frj^^ afeSJf"

"*% '2 <w^Fi-?2&' >l ^J&-FemA^°
J?«/TX>-li-(< ) %

--6J 8 \ I A JO. •*»>, -*>,

9 B ^-V 3 %

\

' \«

i \ V* 9 w.

&&&

* \» , «\.''4" « Ji-^'1

V ^ J. % JO «0. <?_ . 21 I >— A

2i 2

l( ^

'Vy0*'^
X>

\

'Pt

,^

^Siparia

\<5«^

53€^-

3j

21

l4

J 2

I Redo

--¥: '--?->^
b-,,-'2V~-13^

23 2C
I5\ 18 17

35 \ 2I 29

„ Pta Bombeador — 'm>.\ 31

I Pte PescBdorV"^^^ °\35 29

-4,n ,5. 22

ID

'<*»

<?

/

8 \I2

<•

Subsurface

Echosounding

by Tj. H. van ANDEL

(ARLY in 1951, in the Gulf of
Paria, the author was introduced
simultaneously to the beauties of
marine geology and the frustrations
and difficulties of work at sea. The
excitement of this double experience
was such that an interesting phe-
nomenon remained undiscovered until
the cruise was almost finished. This
was the occurrence of reflections on
the echo-sounding records below the
bottom of the Gulf. Such subsurface
reflections had been reported and
speculated upon earlier by a few
American and German investigators,
but had never yet been used system-
atically, although they were known
to be due to the existence of buried
layers of varying hardness. Although
our equipment was embryonic and
the measure of our naivete great, we
succeeded in piecing together many
disrupted occurrences of these sub-
surface reflections, and surmised,
from a variety of circumstantial evi-
dence, that they belonged to a single
surface forming the base of the soft
modern muds and sands of the Gulf.
This resulted in the publication of a
chart of the topography of this pre-
Recent surface and of the thickness
of the modern sediments. Some
knowledge of the geology of the
surrounding land, and of the stages
of slow rise of sea level while it

recovered from a low stand during
the last period of glaciation ( at ap-
proximately 65 fathoms, some 17,000
to 19,000 years ago), indicated that
the buried reflectors might represent
the weathered and hard surface of the
Pleistocene land prior to its flooding
by the sea. The topography of the old
surface was much more complex than
that of the present Gulf floor; mod-
ern sedimentation apparently having
smoothed out many of the irregulari-
ties. It clearly gave evidence for the
existence of a drainage system in the
west connected with some minor
streams that still exist today, and for
a similar one in the east related to
rivers on Trinidad. However, there
was no trace of any valleys that
might represent the Pleistocene
equivalent of the two large Orinoco
river tributaries that nowadays enter
the Gulf, and we were forced to
conclude that the entire northwestern
portion of the Orinoco delta is a very
young feature.

Elegant hypothesis

Although all this was published
with the appropriate amount of
courage and decisiveness, the mem-
ory of the poor and fragmentary
records and of the exceedingly cir-
cumstantial nature of the evidence
remained vivid, and was by no means
alleviated by the beautiful work

6

done on subsurface echosounding in
recent years with more advanced
equipment. When, therefore, in 1960
Dr. V. T. Bowen offered me the oppor-
tunity to return to the Gulf and do
some work of my choosing on the
return of 'Chain's' Equalant I cruise,
I accepted with this problem prim-
arily in mind. It might have been
wise to leave well enough alone and
not run the risk of having to retract
fully an early and elegant hypoth-
esis, but scientists are forever opti-
mistic and the temptation of modern
equipment and facilities was great.

Many reflectors

It is too early at the moment to
assess fully the results of this study,
which at the moment of writing is
still continuing, but the presence of
subsurface echos was beautifully con-
firmed. In fact, we found so many
subsurface reflectors that it will be
difficult to ascertain with confidence
which one it was, if it was a single
one, that we charted in 1951. The
general picture that has emerged so
far appears to confirm in general the
earlier conclusions, including that of
the absence, until very recently, of
Orinoco drainage into the Gulf
proper.

Dr. van ANDEL is Associate Research
Geologist at Scripps Institution of
Oceanography. He will be at Woods
Hole this summer as a Post Doctoral
Fellow.

Moreover, as is so often the case,
the more sophisticated capabilities of
the Precision Graphic Recorder have
introduced considerable complexity
in places where the situation orig-
inally appeared simple. A good
example is shown in the accompany-
ing photograph of a record obtained
in the Serpent's Mouth, the south-
eastern entrance to the Gulf between
Trinidad and the Orinoco delta. The
record, clearly shows a protruding,
relatively steep-sided mass of hard
bottom, covered on both flanks with
well-bedded modern sediment. This
ridge, probably Tertiary in age,
appears to connect the Peninsula of
southwestern Trinidad with the
Orinoco delta, where its presence in
the subsurface is known in an oil
field at the edge of the large estuary
opening into the Gulf. On the Trini-
dad side several oil fields both on
land and in the shallow Gulf have
been developed in the ridge. The
position of the top of the ridge is
such that it may well have barred
the Serpent's Mouth until some seven
or eight thousand years ago.

Echosounder record of partially buried,
pinnacled Tertiary ridge (right) adjacent to
well-bedded modern sediments in a trough
of complex structure (left). The total height
of the record represents the interval of
0-40 fathoms, the width a distance of
approximately 2 nautical miles.

1

R. V. CRAWFORD'S

WORK

by W. G. METCALF

A:

.S an aftermath of the 1961 Equa-
torial Cruise of the 'Chain' to the
Romanche Trench during which
measurements were made of the
Atlantic Undercurrent,* a somewhat
more elaborate plan was devised for
further equatorial current studies
using both 'Crawford' and 'Chain' in
1963.** This plan mushroomed into
an extensive international effort
known as Equalant I. (Note: Equa-
lant II, a continuation of the interna-
tional effort will take place during
July and August 1963, but our Insti-
tution is not participating.) The U.S.
Bureau of Commercial Fisheries has
taken on the task of coordinating the
efforts of the various co-operating
agencies.

The present article concerns 'Craw-
ford's' work in Equalant I between
mid-January and the end of April,
1963. With a scientific party of eight
we left Woods Hole on 18 January
and headed for the Cape Verde
Islands via Bermuda. Except for a

8

The 'Crawford' also had
a foreign visitor on board.

50

bathythermograph profile on the
Bermuda-Cape Verde Islands passage
and a few plankton tows, the scien-
tific program did not start until after
the ship left Sao Vicente and headed
south along the 25th W. meridian.

Hydrographic stations, augmented
in most cases in the upper 375 meters
by in situ salinometer lowerings,
were occupied every full degree of
latitude (60 miles) from 15° N. to
10° S. Between 5° North and South,
the interval was reduced to 30 miles.
This general pattern was followed
on all the sections. North-south sec-
tion were run at 25°, 27V20, 30°,
32y2°, 35°, and 40° West, and addi-
tional sections were run connecting
the southern ends of the 25° and
321/2° sections with the Brazilian
shelf. A total of 174 stations were
occupied.

On three Equator crossings, para-
chute drogues were placed in the
Undercurrent at about 55 meters, and
in all cases the subsurface drift was
at a speed of about IVa knots to the
East. In general, the surface current
flowed to the West if the Trade
winds were blowing. On some occa-
sions when the air was calm the
surface current was either lacking or
was running to the East.

Unfortunately the in situ salino-
meter only functioned on two of the
crossings but the information it gave

*See "Chain Cruise #17", Oceanus, VIII, 1,
Sept. 61

**See: "Equatorial Studies", Oceanus, IX, 2,
Dec. 1962

40

30

20

10

W

10

• Buoys — Chain

o Buoys — Lomonosov

10

N

10

Tentative cruise plan for the Equatorial
region shows where our ships and those of
other nations operated. The dots indicate

where our R.V. 'Chain' and the Russian

'Lomonosov' set out Richardson current

meters on buoy stations.

was of immense value in delineating
the salinity maximum which is such
an important feature of the Under-
current.

Electronitis

A current meter designed to be
lowered from the ship refused to
work properly. After years of exper-
iences of this sort, I have reached the
inescapable conclusion that electronic
devices are very apt to malfunction
on any ship I am aboard. I used to
think that vacuum tubes found my
presence incompatible, but have
recently come to realise to my sorrow
that transistors feel the same way.
The new transistorized PGR put up
with me for a total of 18 hours before
quitting for the rest of the trip.

Fortunately, Nansen bottles and
reversing thermometers are less tem-
peramental in my presence, and the
hydrographic data appear to be very
good. In conjunction with the current
records from the 'Chain' part of the
cruise, these results should give us
new and interesting information
about the Undercurrent which must
play a major role in the distribution
of biological and chemical products
in the equatorial region.

On all the Equator crossings, the
core of the Undercurrent showed a
salinity of about 36.5 o/oo. Along the

coast of Brazil, a narrow but well
defined subsurface core of water
with a salinity of greater than
37.0 o/oo was found between 50 and
100 meters in depth, which appears to
be the source of the saline core of the
Equatorial Undercurrent.

In general, the temperature picture
gave little evidence of either a north-
westerly current along the coast nor
of the Equatorial Undercurrent. A
slight spreading of the isotherms in
the main thermocline could be seen
at the Equator but it was not very
pronounced in most of the crossings.

Navigation

Although much interesting work
remains to be done on the current
system close to the Equator, much of
it must wait until some of the newer
navigational techniques become
available to us. In an area such as
this, where variable and unknown
surface currents are at work and
cloudy skies are often present for
prolonged periods of time, celestial
navigation is uncertain enough to be
a seriously limiting factor in the
accuracy of current observations. It
is hoped that good Loran coverage or
the use of an inertial navigation
system will solve some of these
problems.

10

I

Equa/anf

Buoy

Program

A most successful moored buoy program was carried out during the 'Chain-35'

participation in the Equalant Program.

B

'UOY work along the Woods Hole-
Bermuda line* was discontinued in
the autumn of 1962, in order that the
equipment would be ready for the
Equalant I Program. Twelve buoys
crowded the afterdeck of the 'Chain',
while the associated instruments and
anchoring equipment took up con-
siderable space in other parts of the
ship.

Seven of the stations were estab-
lished on a long term basis of ap-
proximately two months on and near
the Equator. The buoys were pro-
grammed to record current speeds
and directions three times per hour.
Of these seven, three were recovered
on station, two were picked up adrift,
and two were lost.

The remaining five buoys were
used for short term measurements,
of approximately one week each,
with the instruments set to record
continuously. Each buoy was set out
four times and was recovered each
time without loss of instruments. We
were most pleased with the results
of this successful experiment.

The current meters suspended at
various depths, constituted the bulk
of the instrumentation but some
thermographs were also installed. In
addition, several recordings were
made of mooring tension, in line with
our continuing efforts to improve the
design of the mooring.

by PAUL B. STIMSON

Modern electronic aids to naviga-
tion do not extend to the Equatorial
Atlantic so that the positioning prob-
lem proved to be a crucial element
in the buoy program. Celestial fixes
were obtained whenever possible but
there were extended periods of dense
cloud cover which left us dependent
upon dead reckoning.** Fortunately,
each buoy was fitted with a small
beacon transmitter fitted with a
newly designed keyer which caused
it to emit an identification signal
once every few seconds, instead of
once an hour as was formerly the
case. The 'Chain' carries a good radio
direction finder. Invariably the detec-
tion of a radio signal led to the
speedy recovery of the buoy.

Mr. STIMSON is in our Department
of Applied Oceanography with Dr.
W. S. Richardson.

*See: "Current measurements from moored
buoys", Vol. VIII, No. 2, Dec. '61.

**Deduced from courses sailed, ship's speed
and known or estimated drift.

11

Some Statistics

Major Purpose: Two of our research vessels took part in
"Operation Equalant I", from January through May, 1963,
to study the Atlantic Equatorial region.

Total miles sailed: 'Chain' (Captain C. A. Davis)
15,878 miles. 'Crawford' (Captain D. F. Casiles)
15,054 miles.

Ports of call: 'Chain': Bermuda, St. Thomas, V. I.,
Recife, Paramaribo, Port of Spain, St. Thomas,
V. I.

'Crawford': Bermuda, St. Vincent, Cape Verde
Islands, Recife, St. Thomas, V. I.

Personnel: 'Chain': 43 scientists (not at any given time).
Chief scientists: Dr. W. S. Richardson (legs 1 and 2),
Dr. V. T. Bowen (legs 3 and 4).
'Crawford': 12 scientists under Mr. W. G. Metcalf.

Data: 'Chain': 6 Hydrographic stations, 94 plankton tows,
12 piston cores, 22 gravity cores, 57 dredges (rock, pipe,
shell and quantitative) , 6 large volume stations, 33 mid-
water trawls, 27 moored buoys set out (25 recovered)
utilizing some 25 miles of braided nylon and polypropy-
lene mooring lines, 2 scattering layer stations, 9 shallow
salinity and pH stations (upriver in Venezuela by small
boat), 61 chlorophyll stations. Continuous or repeated
observations: bottom profiles with PGR, CO2 measure-

fc.tu.fej ,

ments, bioluminescence counts, Bathythermographs, verti-
cal profiles of salinity and oxygen, visible counts of marine
life and birds, nightfishing.

'Crawford': 174 Hydrographic stations, 5,067 temperature
observations, and 5,067 salinity determinations, oxygen
titrations, total phosphate, in situ inorganic phosphate, 64
in situ salinity lowerings, 6 large volume stations providing
46 water samples, 1226 Bathythermograph observations,
14 plankton tows, 12 sea surface radiation measurements,
5 parachute drogues, 4 surface drogues, 3 anchored buoy
stations, 2 Swallow floats, 2000 drift cards set out, continu-
ous sea surface temperature records, 75 cloud photographs.

Working visitors on board the 'Chain': Leg 1; Dr.

N. B. Marshall, British Museum; Dr. P. Koske, Kiel
Univ. (W. Germany) ; Mr. R. W. Mosher, U. S.
Weather Bureau. Leg 2: Dr. G. D. Nicholls and
Mr. G. Thompson of the University of Manchester
(Gr. Britain); Dr. Maurice Rinkel, Miami Univ.;
Mr. E. Eckstein, Univ. of Sao Paulo (Brazil) ; Dr.
I. Macgregor, Princeton Univ. Leg 3: Dr. Tj. van
Andel, Mr. R. Gibbs, both of Scripps Inst. of Ocean-
ography; Dr. R. Cifelli and Dr. D. Squires, U. S.
National Museum; Dr. N. Sachs, U. S. Geological
Survey; and Lt. R. Salas, observer for the Ven-
ezuelan Navy. (See also page: 20). Naval Evalua-
toin Group for the GEON: Warren A. Stickney,
Naval Applied Science Laboratory; Ralph H.
Thrasher, Bureau of Ships; Louis Larsen, Naval
Applied Science Laboratory; Bruce Sammitt,
I.T.T. — Federal Laboratories.

Varied!

'xpenence

By R. GIBBS

By various methods of travel, from floating in dug-out canoes and eating monkey
meat, to sailing in the 'Chain' and dining on filet-mignon, the suspended materials in

and from the Amazon river were sampled.

iVERYONE who has seen tropical
or subtropical waters has been in-
trigued by the brilliantly blue hues
and the clarity of the sea. Yet, clear
as this water appears it contains a
lot of suspended materials as well as
dissolved salts. The vast majority of
these materials are supplied by rivers
to the ocean, yet very few studies
have been made of this incoming
flow.

There are many intriguing ques-
tions that need to be answered. What
are the types of material arriving
from different rock areas? What
changes occur in the material en-
route to the ocean? Where does the
material go in the sea? To try to
answer these questions we selected
the Amazon river system, since it is
one of the few rivers left in the world
which are not seriously disturbed by
man through dams, sewage, agricul-
tural activities, etc. Also, the Amazon
system has the widest range of
climatic conditions, from the Arctic
type of region in the Peruvian Andes
to the tropical rain forests.

The plan for the river work was
to sample periodically the tributary
rivers which bring materials from
various climatic and geological areas
and to visit each region in the dry
and rainy seasons to make other
measurements such as temperature,
pH, eH, etc. The inaccessibility of the
areas and the very difficult travel
conditions obviously make it impos-
sible to visit the areas regularly. In
two months of difficult field work we
managed to establish ten sampling
stations where doctors, missionar-
ies and scientists living along the
rivers will sample the water every
two to four weeks. This also permits
a survey of the conditions during the
wet season which lasts from Decem-
ber to May and during which time
travelling becomes even more diffi-
cult.

Monkey meat

The river work entailed travelling
from the mouth of the Amazon up
into the foothills of the Andes, a dis-
tance of approximately 3500 miles,

14

using every possible means of trans-
portation, from airplanes (when
available) to small dug-out canoes.
The conditions of "lodging" were far
from desirable. Many a night was
spent in my U.S. Marine surplus
jungle hammock hanging from a
couple of trees along the river bank.
Usually, however, I managed to be
in some village at night, for they
were my chief source of food. Need-
less to say there were no Duncan
Hines recommendations, the food in-
cluded such delicacies as monkey,
boa constrictor (anaconda) and a
multitude of exotic fruits and vege-
tables. Arranging for a canoe was a
matter of finding some Indian who
had one and bargain for a price. The
usual rental for a good dug-out and
a strong man to paddle from dawn
to dusk was from 50 cents to one
dollar.

Later on, in the estuary of the
Amazon a brief survey was made of
the conditions of the materials and
what happens when they first come
into contact with salt water. This
entailed the use of an in-situ trans-
parency and salinometer, current
meters and sampling devices. The
work was easier since I. C. O.M.I., a
division of Bethlehem Steel at Sant-
ana, Amapa, kindly made one of their
barges and tugs available.

The outflow of the turbid Amazon
waters are carried northward along
the Atlantic coast by the North Equa-
torial current. This discharge can be
seen from the air as a zone of brown-
ish turbid water extending ten to
twenty kilometers out to sea. It can
be traced easily for more than 1600
kilometers as far as the Gulf of Paria.
To obtain information on this out-
flow, I joined the R.V. 'Chain' and

worked also from the M/V 'Oregon'
of the U.S. Bureau of Commercial
Fisheries and the destroyer 'Bertioga'
of the Brazilian Navy. All these ships
took part in 'Operation Equalant'. I
received the kindest co-operation
from the officers and scientists on
board these vessels.

Shark supper

The cruise on board the 'Bertioga'
was made possible through the kind
efforts of the Oceanographic Institute
at Sao Paulo. About halfway through
the cruise the "Langosta guerria"
with the French lobsterman started.
Being a naval vessel we merrily went
along the waves carrying on gunnery
practice after the French boats.
Another sidelight was the fondness
of the crew for catching sharks while
we were hove-to on hydrographic
stations. And guess what we had for
supper on those nights?

To obtain sufficient material for
analysis each water sample from the
rivers had to be from 20 to 40 liters
and in the ocean from 40 to 100 liters.
Each sample was then filtered using
special pressure apparatus and micro-
filters. A pressure head was obtained
by hoisting plastic bags high up on
the mast of the 'Chain'. Extracting
suspended materials from such large
volumes of water proved to be a
difficult problem. So, for laboratory
analysis onshore, all the suspended
material from each sample and be-
tween one and two liters of the
filtered water was stored. We are
now anxiously awaiting the results of
our chemical and mineralogic an-
alyses for only then can we distin-
guish between the various suspended
materials which, like cats in the
dark, all look about the same on the
filters.

Ed. note: Unfortunately no photographs were available to illustrate
Dr. Gibbs' fascinating cruise up the Amazon River.

M

.ORE and more articles which have appeared in Oceanus are reprinted
by permission in various other periodicals and newspapers.

The article: "Whale music" by Wm. E. Schevill in the December 1962
issue was reprinted in Vol. XVI, No. 4 of Naval Research Reviews. The
article: "Education" by G. E. Stokes, published in the March 1963 issue,
will be reprinted in Science and Mathematics, a High School publication
published by the Weslyan Press.

15

The intensity of the search made for the Thresher by the 'Atlantis II' is shown on this
chart superimposed on the bottom contour chart resulting from the extensive search.

Depths in fathoms

16

Thresher Search

JL HE search for the lost submarine
'Thresher' has been so widely
reported in the newspapers and other
periodicals that we cannot hope to
compete in the reporting of this
dramatic undertaking. Instead we
shall give a brief account here,
especially brief since everyone at
Woods Hole has been busy. We hope
to be able to provide an adequate
background story in the near future.

By chance, the 'Atlantis II' was
within 100 miles of the area where
the 'Thresher' disappeared on April
10th. Our ship was on her second
scientific cruise, making biological
and chemical observation in the Gulf
of Maine. Upon hearing of the
disaster, our Director, Dr. Fye, offered
the services of the 'Atlantis II' and
the facilities of the Institution to the
U.S. Navy. Consequently, our new
ship arrived in the search area in the
morning of April llth. From that
date, until May 28th when the
'Atlantis II' was released by the Navy
to resume her interrupted scientific
schedule, she played an important
part in the search operations, princi-
pally because of our ability to dis-
tinguish small protuberances on the
ocean bottom with our Precision
Graphic Recorder, and due to the
"know-how" of our ship's officers,
crew and scientists in the study of
the ocean bottom. A large number of
our people took part under the
leadership of Dr. J. B. Hersey, Chair-
man of our Geophysics Department.

S. T. Knott anxiously scanning the
PGR on board the 'Atlantis II'.

The Woods Hole work at sea on
'Atlantis II' consisted of four separate
cruises led in turn by N. Corwin,
S. T. Knott, J. B. Hersey, E. E. Hays,
W. Dow, and S. T. Knott again. The
effort, in the search area, roughly
220 miles east of Cape Cod, consisted
mainly of locating bottom irregulari-
ties which might be the 'Thresher's'
hull, using echo-sounding techniques*
and then to examine these protuber-
ances more closely with other
instruments, chiefly underwater
cameras.

Debris shown

The difficulty of positioning a cam-
era at the end of \l/2 miles of cable
over a precise spot only a few
hundred feet in size hardly can be
overstated. When we went to press
no photographs identifying the
'Thresher's' hull had been taken.
Quite a few photographs, however,
showed debris which might or might
not have come from the submarine.**
These photos, together with other
information were deemed sufficient
to concentrate the search in one
particular area.

Meanwhile, Navy and civilian
scientist analyzed the evidence ob-
tained and tried to narrow the search
area.

*See: Oceanus, Vol. V, nos. 1 and 2. 1957
**See: Life. June 7, 1963

Commendation

The following message was received from Vice Admiral A. Grenfell,
Commander Submarine Fleet Atlantic. "1. Through all phases of 'Thresher'
search and survey to date, performance, by the 'Atlantis II' has been marked
by the highest standards of seamanship and scientific performance.

2. Please express my appreciation to your dedicated team of scientists and
seamen for their assistance in a difficult task. Their efforts have con-
tributed significantly to oceanographic knowledge and to our capabilities
at deep ocean depths."

17

I

18

THROUGH this night the ship moves as on a sea of watered silk; softly
lighted by the past-full moon which keeps easy pace at the end of a
slowly writhing path of light. The ship is unnaturally still as she pushes
a circle of awareness through the vacant tropical sea. Beyond the hard
line underscoring the moon's place in the night, there is no end of sea;
no beginning of sky. The ship is without support; balanced precariously
on the very tip of a finger of light. The soft wash of the bow wave hints
that the ocean may still be real and may still be sliding past her sides.

On deck all are silent. The coming sounds of those who burst
from the lighted spaces below are at once subdued; then cease.
Thoughts carry across the night in contemplation of the sea; then
onward over the curve of earth to those beloved, dimly remembered
in voice and feature, but at this moment a presence vividly recalled.

The mate and lookout stand apart, watching the sea and the
ship as duty requires. What words they need are few and passed in
lowered tones. The helmsman gives his traditional repetition of orders,
but softly, for even inside the wheelhouse this night has special qualities.

At length a figure by the rail owns quietly 'this is what we
come to sea for,' and the silence of the others is clear acknowledgment
that he put it well enough.

Anon.

19

Pinnacles

on tlie

Continental Shelf

_45 FMS

_ 55 FMS

60 FATHOMS

ONE NAUTICAL MILE

by D. F. SQUIRES

A wall of cemented materials was discovered off the Orinoco River. The dredging of
such material from small pinnacles proved a difficult task.

.LONG the margins of the con-
tinental shelf where the land gives
way to the deep sea, one often finds
masses of calcium carbonate and
limestone which form spectacular
topography. These masses of cal-
careous rocks can be grouped to-
gether as shelf edge prominences but
are of diverse origins. The most
conspicuous ones are the tropical
coral reefs. Structures such as the
Great Barrier Reef of Australia
stretch for a thousand miles in a
tremendous accumulation of carbon-
ate rock derived from the skeletons
of the animals living on the reef.

Deep coral

Less well known are the deep
water coral banks such as those
recently discovered by the 'Atlantis'
on the Blake Plateau off the Caro-
linas. Along the edge of the shelf in
the eastern Atlantic, coral banks
form a conspicuous topography.

A third type of prominence is that
formed by an accumulation of shell
material of some antiquity which has
become cemented to form a hard
resistant rock. How the shells accu-
mulate in such mounds varies from
place to place, but the general pro-
cedure is linked to the lower sea
levels which existed during the Pleis-
tocene glaciation. In the Gulf of
Mexico pinnacles have been left
behind as eroded remnants of such
former deposits.

Early studies of the Orinoco Shelf
region disclosed the presence of
masses of calcareous rock on the outer
portion of the shelf. Preliminary re-
ports indicated that these might be the
remains of old coral reefs drowned
during the post-glacial sea level rise.
Echo-sounder records also suggested
that some of these erosional stacks
were small enough to qualify as
pinnacles.

20

With this knowledge, it was plan-
ned, as part of the other shelf sedi-
ment studies to be carried out on
'Chain 35', to study the topography
of the prominences by means of the
Precision Graphic Recorder and to
determine their composition by sam-
pling with the pipe dredge and the
rock dredge. The project was a great
success.

Wall discovered

Among the more notable discover-
ies concerning the shelf edge promi-
nences was that west of a position
roughly corresponding to the mouth
of the Orinoco River, the discrete
pinnacles found to the east gave way
to a continuous wall for which the
name Orinoco Wall has been sug-
gested. This structure extends along
the shelf in depths of from 45 to 65
fathoms as an unbroken' wall about
five fathoms in height and varying
from several hundred feet to nearly
half a mile in width, and possibly
extending for one hundred miles. To
the east of the Orinoco River mouth,
the wall has been broached and
eroded. PGR tracings from some
crossings of the shelf edge showed
the prominence to be completely
missing, others indicated that only
narrow remnants were still present.
Nevertheless, this more or less con-
tinuous structure is of great signifi-
cance both to the interpretation of
the physical environment of the shelf
and to the biology of the region.

Sampling the structure of the wall
was relatively easy, but dredging the
pinnacles was another matter, for
many of them were less than 200 feet
in diameter and were about 30 feet
high. This small target had to be hit
from a ship hove-to in an area sub-
jected to a current of from two to
four knots. The technique for study-
ing these pinnacles was based upon
the ship maneuver, the Williamson
Turn, which is used, in the event of a
man overboard, to bring the ship
back on its original track, but pro-
ceeding in the opposite direction.
When 'Chain' approached the shelf
edge, a marker buoy was readied on
the fantail. If a pinnacle was crossed,
the bridge was asked for a William-
son turn, and as 'Chain' passed over

Dr. SQUIRES is Associate Curator,
Division of Marine Invertebrates, at
the Smithsonian Institution.

the pinnacle for the second time, the
buoy anchor was kicked over the
side. It is a tribute to the ship's
officers that in one instance, four
crossings were made at full cruising
speed of a single pinnacle (two at
right angles to the preceding two)
the pinnacles being only two ship's
lengths in total diameter.

Dredging of the pinnacles and of
the shelf in their vicinity yielded
much information concerning the
setting and composition of ,the rock.
However, it was not until after the
Orinoco Wall was discovered that an
attempt at knocking off rock was
successful. There, where pinpointing
the structure was not necessary,
greater attention could be given to
the placement of the gear. The wall
is composed of masses of shell ma-
terial, pebbles and sand cemented
together by a means not yet known,
all of which is grown over by a liv-
ing mat of calcareous algae. A fauna
of solitary corals, molluscs, sponges,
and many other organisms were
associated with this calcareous algae.
There is no evidence that the wall or
the pinnacles are a coral reef, or that
they represent the remains of one.
This information will have to wait
complete study of all the samples
collected.

Bottom photo of living coral (white) and dead debris
(black) on deep coral bank on the Blake Plateau.

Ye monstrous of the briny deep, your masters

praises shout. Up from the waves ye cuddlings

peep, and wag your tails about.

(Bay State Hymn Book)

"O ye Whales and all that move in the waters. . . ."
(the Book of Common Prayer)

and little sharksey doyster, —A squiddly

doyster too "

(Mairsey dotes)

.LnOM the pious Pilgrim hymn to
the solemn prayerbook and the child-
ish prattle of a once-popular song,
man frequently refers to the crea-
tures of the sea. Denizens of the
deep, particularly the big ones, have
fascinated man ever since he decided
to venture forth on the surface of the
oceans. Fleeting glimpses of large
sharks and whales have stirred the
imagination and provided material
for many a long sea story. However
these are vertebrates and have a
fairly commonplace and familiar
body form in spite of their enormous
size. Monstrous invertebrates, on the
other hand, really can be startling,
not only because of size but parti-
cularly because of a grotesque ap-
pearance.

Giant

By H. J. TURNER

In general the invertebrates are
small. The average landsman seldom
sees one any larger than an earth-
worm, spider or grasshopper, while
a two inch tarantula or a six inch
centipede may inspire terror. Some
people have marvelled at a two-foot
lobster in an aquarium, or admired
the three-foot shell of a giant reef clam
serving as a bird bath on a concrete
pedestal, but these are not common,
and not startlingly big. In fact the
structural and functional biology of
invertebrates is such that great size
is almost impossible to attain. Never-
theless, one exceptional group of
marine molluscs, the cephalopods,
have managed to develop species of
considerable size.

Strange creatures

The cephalopods, a group which in-
cludes the squids, octopuses, cuttle
fishes and nautili, are molluscs like
clams, oysters and snails. The cepha-
lopods are quite advanced in a num-
ber of ways. They swim by means of
jet propulsion and may be among the
swiftest of marine organisms when
they dart for short distances. They
have extraordinarily well developed
eyes which are similiar in many
respects to the eyes of vertebrates.
They capture their prey with sinu-
ous arms provided with adhesive

22

suckers and bite with beaks very
much like those of birds of prey.
When startled or frightened they
release clouds of an ink-like sub-
stance which may either act as a
smoke screen, or otherwise distract
an adversary and permit a successful
retreat. On the whole they are quite
extraordinary creatures.

Largest invertebrates

One group of cephalopods, the
squids, contains species that are the
largest invertebrates in existence.
While most of the squids are about a
foot long or less, there are a few
kinds that attain relatively great
size. The giant squid, Architeuthis,
may have a body as long as twelve
feet and when the dimensions of the
two tentacular arms are added, the
total length may reach 50 feet. An-
other kind, Sthenoteuthis, is some-
what smaller but still may reach
quite impressive dimensions.

Specimens of these big squid are
rarely found since they are all in-
habitants of the deep oceans. Those
that have been seen have usually
been stranded on beaches, or found
in the stomach of sperm whales and
almost always have been more or
less decomposed before coming to
the attention of the biologist. Conse-
quently, the finding of a specimen,
or even a portion of one, in good
condition is an exciting event.

Mr. TURNER is a Marine Biologist on
our staff and lecturer in Zoology at the
University of New Hampshire. He has
been with the Institution since 1944
when he came to work on the wave and
surf project and subsequently on the
anti-fouling program.

On the 'Chain-35' cruise, a portion
of a squid tentacle of considerable
size was caught between the top of
a Nansen bottle and the hydro-
graphic wire at one of the stations
south of Bermuda. When the news
first reached the laboratory, it had
passed through several persons and
had grown considerably with the
telling. The tentacle was reported to
be as big as a man's leg with sucker
discs like dinner plates. More reliably
informed sources indicated that it
was quite a bit smaller, and when the
ship docked the tentacle was found
to be preserved in a pint mason jar
although packed in very tightly.
There is no way of knowing at what
depth the tentacle was caught. The
Nansen bottle had been tripped at
3100 meters but probably encountered
the squid on the way up and
wrenched off a portion of the ten-
tacle as the wire was reeled in
rapidly. The tip was still writhing
when it hit the deck.

Part of the tentacle of an
8 to 10 foot long squid,
found by the 'Chain', as com-
pared to the equivalent tip
of a one foot squid. The two
tentacular arms deflected to
the side are not much longer
than the other eight arms of
the small species. In the body
of the giant squids these arms
are about one third longer
than the body of the animal.
The size of the suction cups is
indicated by a five cent coin.

JWf'i'

a:
ui
z
o
o
a.

U)

23

The specimen proved to be the
club-shaped, sucker-equipped, end-
portion, or manus, of the long arm of
a squid, probably of the genus
Sthenoteuthis. The biggest sucker
was about as large as a nickel. By
comparison with the published
dimensions of intact specimens of
this genus, it was possible to recon-
struct the size of the original animal.
The body was at least three feet long
and possibly nearly four feet. The
two long arms were from four to six
feet long so that the total length of
the squid was nearly ten feet. This
is by no means a record but would
have been quite impressive if the
entire animal had landed on the deck
with writhing arms, and jetting ink.

Our interest in these big squid is
somewhat more than academic. We
suspect them of biting the mooring
ropes of deep sea installations and
setting the buoys adrift. The mooring

ropes of at least two drifting buoys
have been recovered which give
some indication that this may be the
case. Two of the three strands of
polypropylene rope were cut off
cleanly and the third was frayed out
as if from simple stress failure. A
siphonophore, a long, stringy jelly-
fish-like organism, was wound around
the rope near the cut ends.

We believe that the siphonophore
may have been one of the lumines-
cent variety and may have flashed
its lights when it became entangled
with the rope. The squid, seeing the
flashes, may have then seized the
rope with its tentacles and attacked
the siphonophore with its beak. When
it cut through two of the strands of
rope, the third parted with a quick
snap which must have surprised the
squid considerably. Some day we hope
to catch one of these large squid alive
and perhaps determine whether or
not this hypothesis could be correct.

. * •

New Aircraft

J. HE Institution's new four-engined airplane (Capt. Wm. Ewing), and
which has what almost amounts to a novel written on her tail, left Woods
Hole on June 3d for her first scientific flight in co-operation with the U.S.
Weather Bureau. Meteorological observations will be made over the Indian
Ocean, using Bombay as the home port.

Mr. Andrew F. Bunker, who has logged many thousands of hours on
our planes, is chief scientist, assisted by Messrs. F. C. Ronne, C. P. Brown
and R. B. Bachelder.

24

MBL WHOI LIBRARY

WH 17ZD J

Associates' News

JL HE Associates' dinners held in May were well attended by Associates,
their guests and prospective Associates. 216 people attended the meeting
in Wilmington, Delaware, 212 were present in New York and 215 dined in
Boston. Our Director, Dr. Paul M. Fye, was the principal speaker and
provided a review of our new ships, and other facilities. He also discussed
the Thresher search and the two international programs, in the Indian
Ocean and along the Atlantic Equatorial region.

Yacht Club Visit

J_ HE Commodore of the New York Yacht Club, Mr. H. Irving Pratt, has
accepted the Institution's invitation for an open house visit when the fleet
of yachts dock in Woods Hole this summer during their annual cruise.
This will be the second affair, the yachtsmen visited also about ten years
ago. Last summer several hundred members of the Cruising Club of
America received a welcome and listened with pleasure to a series of
informal talks by staff members

.HE ASSOCIATES of the Woods Hole Oceanographic Institution are a group
of individuals, corporations and other organizations who, because of their love
for the sea and interest in science and education, support and encourage the
research and related activities of the Institution.

Membership dues in the Associates are as follows:

Member $50

Contributing Member $100

Patron $500

Life Member $1,000

Corporate Member $1,000

Sustaining Corporate Member $5,000 or more.

All contributions and dues are tax deductible to the extent provided by law.

HOMER H. EWING, President

RONALD A. VEEDER, Executive Assistant

EXECUTIVE COMMITTEE

CHARLES F. ADAMS PAUL HAMMOND

W1NSLOW CARLTON NOEL B. McLEAN

RACHEL L. CARSON HENRY S. MORGAN

W. VAN ALAN CLARK MALCOLM S. PARK

PRINCE S. CROWELL GERARD SWOPE, JR.

F. HAROLD DANIELS THOMAS J. WATSON. JR.

JOHN A. GIFFORD JAMES H. WICKERSHAM