U. S. Geological Survey Open-File Report 01-154

Cruise Report - R/V Gosnold 13

PURPOSE: 

Bottom sampling and photography. Fill in bottom sampling stations in gaps in Georges Bank - Browns Shoal area.

DESTINATION:

Georges Bank - Southwest part

DATES:

TIME ZONE:

9-14 May, 1963

EDT

SCIENTIFIC PARTY:

Jobst Hulsemann
Russell Paul
Donald Casey
James Trumbull
John Hathaway
Elazar Uchupi

TOOLS:

• Campbell grab with built-in camera (Robot) and Strobe 

• flashlight

• Velero shaker table rigged

STATIONS:

1053 - 1084

CRUISE NARRATION:

Departure Woods Hole 10:00 on 9 May. First station at Southwest entrance to Vineyard Sound.

The routine shipboard processing of a bottom sample consists of:

1) measure volume of total sample recovered

2) procure sample from what seems to be surface material and add to it Rose Bengal solution Foram. sample, quantity 200-400g;

3) procure representation samples in a.) one pint b.) one half pint containers = Sediment sample;

4) Wash remainder of recovered sediment through screen(s) using 1mm opening as the finest. Discard material finer than 1mm, collect material coarser than 1mm in appropriate container(s), add to it 57o Formalin solution = Biological sample.

5) If free from sessil organisms, rocks or representative cuts of the rocks can be collected in bags or other adequate containers.

6) Take a picture of a piece of paper bearing the number of the station just completed.

Such routine bottom sampling continued for the rest of the day in the area south of the islands of Martha's Vineyard and Nantucket. Dominantly the material consists of green to brown silt or sand and shell debris. In 5 out of 6 lowerings of the grab the recovery was between. 4 and 12 liters, in one case it was 35 liters. Two readings were made with the Secchi disk. Weather was partially cloudy with wind from S force 3-5. Overnight steaming brought the ship to the Southwest part: of Georges Bank where routine sampling continued on the 10th of May beginning at 07.00 with 7 stations gaps in sample pattern were filled between Oceanographer Canyon and Hydrographer Canyon. The maximum depth was limited to near 500 m because of camera equipment. Maximum recovery of a single grab was 10 liters. The sediment consists chiefly of greenish grey silt and sand with the exception that also greenish blue sand and a piece of rather fresh diabase were obtained on the deepest station (503 m).

During the day the weather turned bad and the report at 18.20 predicted it to become worse, i.e. NE 25 knot wind is said to shift to NW 35 knots. However, at this time the wind blew already with 35 to 40 knots reaching 45 knots in gusts in the working area.

Station 1063 first lowering hit bottom - winch engine quit while grab 3 m below surface, repair time (dirty fuel) 20 min., recovery from this sample: one starfish and about \ pint sand. 2nd lowering made - drift was less than 1 mile: recovery about 1 liter of sand-most of it was washed out of tub by a wave.

Station 1064 handling of grab increasingly difficult. All hands but one on deck - as usual on station - and needed - as unusual, recovery: bucket tripped, no sediment - water haul. No second attempt to grab a sample was made-rather proceed to new station some 11 mi to the north. Waves that wash over the deck become more frequent and bigger. Ship's speed very much reduced (4-5 knots?).

About 19.45 it becomes obvious that next station can not be occupied during daylight. The captain calls for discussion of plans and program. Chief scientist recognizes the hazard of staying in the area during the next 24 hours and deems sampling conditions 1/2f+ unsafe and inadequate, - agrees to captain's proposal to change course to West to Northwest and try to reach the shelter of the Islands of Nantucket and Martha's Vineyard about next morning. Sampling planned in Rhode Island Sound on Saturday. Captain's strong recommendation for changing working area and transfer to South of Rhode Island was based on bad weather "for the ship", and danger for personnel. Forward door of van is not watertight. Any walking about the open deck is dangerous -so up to the wheel house - because of heavy seas that run over the ship. Heavy breakers coming over forecastle. Hazard is seen in handling the heavy bucket, failure of sampling is seen in fast up and down motion of the ship which may trip the bucket before it touches the bottom, and securing the sample is not warranted on shelterless main deck.

11 May. 0800 - Plans still call for getting in lee of the Island of Martha's Vineyard-if enough daytime is left it shall be tried to occupy stations in Rhode Island Sound. If wind calms during night from 11 to 12 May course can be taken towards a series of desired stations South of Great South Channel west of Hydrographer Canyon. Overnight steering would facilitate the taking of some more samples in Southwest part of Georges Bank. If weather stays bad we can try to occupy some more stations in R.I. Sound.

10:15 captain informs chief scientist about weather getting worse, wind is up to 45 mi. from Northwest. Ship remains headed for south of Martha's Vineyard. Anticipated arrival time about 14.00. If possible it will be tried to occupy a station in R.I. Sound of 41^o20'N 71^o15'W, water depth - 20 fms.

16:45 arrived 1 mi. south of Martha's Vineyard and anchored in some 15 m water depth. Weather: strong gale, wind force early afternoon 45 m.p.h. steady gusts up to 55 m.p.h., middle afternoon 40 to 45 m.p.h." Beaufort 9; sea state 6, wave heights 4-5 m = high seas, barometer at 15.00 29.99" hg. outside temper. 42 F; 99% overcast.

Gyro-failure shortly before ship anchored about 16.30 - 17.15, warm up time for gyro needed about 2 hours. Travel time for some 130 mi. from 19.45 on 10 May to 16.45 on 11 May - 21 hours, wind chiefly from abeam, average speed 6.2 knots.

22:30 wind 20 m.p.h. from NE, barometer 30.18"Hg. rising (fast for past 4 hours) outside air temp. 40; 80% overcast. First sampling station planned for next morning 06.00 in Rhode Island Bay.

On 12 May. at 0400 weigh anchor South of Martha's Vineyard and sail south southwest to a place some 45 mi. south of Block Island to occupy the first station. Since midnight the wind was 15 to 20 knots from N, the barometer holds steady at 30.19"Hg. 60% overcast (low Cu), sea state 1-2. The first station of the day, no. 1069, was occupied at 10.30. Here and on 5 more stations routine bottom sampling was observed. The stations are some 10 miles apart and extend from the starting point south and southwest to the continental slope. The material recovered chiefly exists of green fine to medium sand and silt, in cases rich in foram. tests and shell debris. The recovered volumes are between 5 and 70 liters.

Overnight steaming brought the ship to a position some 20 mi. north of the Hudson Canyon, where routine bottom sampling started at 0600 on 13 May, 1963. Nine more stations were occupied during the day between Hudson Canyon, the shelf break and the line of stations south of Block Island worked on the previous day. Again, dominant is green silty sand, partly rich in foraminiferous and shell debris. Bottom life appears to be rather scarce in comparison with Gulf of Maine area, and echinoderms seem to be much fewer than on the shelf off southern California. 70% of the samples had a volume of less than 20 liters, and 3 samples contained between 60 and 95 liters. Geologically the most interesting station, also very different from the others is No. 1078 on the north wall of Hudson Canyon. 95 I of green silt and sand, grey clay and green sandstone were recovered from a depth of 370 m by echo-sounding (uncorrected), or 417 m by wire (no wire angle), the first layer most likely representing the top and 65% of the total volume and the last being the bottom and contributing less than 1%. The penetration of the grab into the seafloor at this station is estimated to not have exceeded 30cm. In addition to routine bottom sampling, several Secchi disk readings were done as on the previous days. Weatherwise, working conditions were good on this day. The wind varied between force 3 and 4 from SW; a swell of about 1 m height was still running from NE.

Sampling was terminated with station No. 1084 and the iof hour run started to Woods Hole. Improvements for operating the grab and the shaker table were listed to be taken care of by the shops after return.

The performance of the Westrex PDR Mark XA was not satisfactory. Bottom trace often too faint or not identifiable at all. Mr. R. Paul, electronic technician improved the situation on the last day. Various reasons given for malfunction.

Performance of the RCA Loran A was very good until the 12th of May, when it became hard to attain the signal of the "slave" station at "function 3". Late that day the instrument was absolutely out of order. The D-X Loran A did not function on the 13th of May.

Sleeping and eating accommodations and sanitary installations can not make an extended cruise attractive to scientists. They must be considered to be below present day expectations and an emergency approach to the need for shipboard facilities. For it is still believed "that good work is not promoted by discomfort."

R/V GOSNOLD berthed at the home deck at 06:20 on 14 May, 1963.