U.S. GEOLOGICAL SURVEY BRANCH OF ATLANTIC MARINE GEOLOGY MEMORANDUM 30 March 1987 To: Distribution From: Jim Robb Subject: Administrative Cruise Report: Farnella 2-87 East Coast GLORIA Survey, Leg II 1. Ship: R. V. Farnella 2. Cruise: 87-2 (Leg 2 of East-Coast GLORIA Survey) 3. Parent Project: East Coast GLORIA Survey 4. Funding Agency: USGS SIR 5. Area of Operations: U.S. EEZ from shelf break to 200-mile limit, Cape Hatteras to Hudson Canyon (approx 33.5 deg N lat, to approx 39.5 deg N lat). 6. Cruise start and end dates, ports: 1 March 1987, Norfolk, VA - 26 March 1987, Woods Hole, MA. 7. Chief Scientist: James Robb USGS AMG Co-Chief Scientist: John Schlee USGS AMG 8. Cruise Data Curator: Nancy Soderberg USGS AMG 9. Scientific Party: IOS Coordinator Malcolm Harris IOS (UK) Geologist Steve Williams IOS (UK) GLORIA engr Chris Flewellen IDS (UK) ABC Computer Linton Wedlock RVS (UK) Mech. tech. Rob Bonner IOS (UK) Photographer Dave Gunn IOS (UK) MassComp tech Mike Boyle USGS PMG Watchkeeper Jim Neiheisel EPA Watchkeeper Millington Lockwood NOAA Emergency Relief Sci Chris Polloni USGS AMG 1-8 Mar 87 10. Ship's Captain: Mike Patterson 11. Purpose of Cruise: GLORIA (long-range sidescan-sonar) mapping of East- Coast U.S. Mid-Atlantic region via contract with IOS (Institute of Oceanographic Science, United Kingdom). This was Leg 2 of a 5-leg effort to map the East Coast U.S. Exclusive Economic Zone (EEZ). Part of the cruise time was spent recovering area designated for leg I but not surveyed due to weather. In turn, some of the leg 2 area was not covered. Unsurveyed parts will probably be covered during leg 4. 12. Navigation techniques: Primarily Loran-C, using an MNS 2000. Auxiliary and backup systems included 2 Loran-C units, a Northstar 7000 system which was also used to provide steering direction on line, and a Megapulse Accufix 500, used primarily for backup. Transit satellite fixes were acquired using an MNS 2000. MNS data, both Loran-C and satellite, were recorded on the IDS ABC data system as lat-lon. Loran-C time-differences from the Northstar 7000 were also recorded on the ABC system. The Megapulse Loran-C data, TD's and lat-lons calculated using a nominal ASF correction, were recorded on 5-1/4" floppy discs using a USGS Loran-C processing and recording program on an IBM PC. Scientific Equipment: IOS GLORIA system (Geologic LOng Range Inclined Asdic) near-surface towed (~50m deep) 6-kHz sidescan-sonar system, 6-11 n mile range (each side) depending on water column sound- velocity profile IOS 2-channel seismic-reflection profiling system using a 160 in3 airgun, Geomechanique streamer, signal digitized and displayed on a CRT in wigggly-trace profile using a MassComp computer (USGS), and recorded on 9-track tape. Towed proton-precession magnetometer (USGS Geometrics gradiometer used with one sensor) IOS 3.5 kHz high-resolution profiler (external fish) IOS 10 kHz precision echo-sounder (external fish) Seas III XBT system (provided by NOAA) 14. Tabulated Information: a. Days at Sea: 26 b. Data acquired: GLORIA images 3300 n. miles SRP profiles on line 3.5 kHz profiles (approx 6100 km) 10 kHz profiled soundings approx 20 xbt profiles, 0700 and 1900 daily Appended: Track Chart Report from Mac Harris, IOS Coordinator Distribution: BC Halley DL Soderberg Cs Polloni ABC Knebel ACS Schlee Sci Twichell GC Booth OCh O'Brien Admin Gail Folger AC Dillon Sci Popenoe OCo Aldrich Sci O'Leary CRUISE REPORT EAST COAST 2 F2/87/EC STATISTICS AND EQUIPMENT PERSONNEL: SCIENTIFIC CREW Chief scientist Jim Robb Captain Mike Patterson Assoc. Chief John Schlee Mate Albert Fuller I.O.S. Coordinator Malcolm Harris 2nd Mate Ian Newsome Geologist Steve Williams Chief eng. Ken Rudd GLORIA eng. Chris Flewellen 2nd eng. George McCann ABC Computer Linton Wedlock 3rd eng. Mark Burnett Mech tech. Rob Bonner Electrician Richard Clarke Photographer Dave Gunn Chief cook Gary Maccorison MassComp tech Mike Boyle 2nd cook Manuelle Merin Watchkeeper Jim Neiheisel Steward Rob Valiente Watchkeeper Millington Lockwood Bosun Alan Thompson Watchkeeper Nancy Soderberg Seaman Pete Appleyard Seaman Coleman Kenny Seaman Jim Springall SURVEY AREA: (Following data are only approximate) Survey area contained within: 39.5N, 7OW and 33.5N, 74W Area surveyed: 36,450 square miles. Length of track occupied during survey: 3,300 miles. Total time occupied by the cruise: 595 hours. Transit time: 58 hours. Time lost due to bad weather: 99 hours. Time lost due to equipment failure: 9 hours. SCIENTIFIC EQUIPMENT USED FOR SURVEY GLORIA, 2 Channel S.R.P. with MassComp, Magnetometer, 3.5 kHz High resolution Profiler, Precision echo sounder and XBT. NAVIGATION: The ship was navigated using the following systems: Transit satellite sampled by MNS 2000 Loran C sampled by NORTHSTAR 7000, MEGAPULSE Accufix 500, & MNS 2000 Omega sampled by MNS 2000 CRUISE LOG The R/V Farnella was due to sail from Norfolk at 0900LT (1300GMT J.D.060) on Saturday 1 March 87, but was delayed until 1230 to wait for the arrival of Chris Polloni who was standing in for Jim Robb until he was able to rejoin the ship. Started the survey at 0348GMT J.D.061. under moderate weather conditions. Weather improved during the following days and at 1026GMT J.D.067 the survey was stopped to return to Norfolk to collect Jim Robb. Started surveying again at 0148GMT J.D.068. Weather deteriorated until winds reached gale force and at 2056GMT J.D.069 it became necessary to leave the survey track and run downwind. Restarted survey at 2341GMT J.D.071 after changing the GLORIA vehicle cable. Survey stopped again at 1650GMT J.D.072 due to bad weather. Started surveying again at start of line 9A 2245GMT J.D.073. Moved off survey line 0132GMT J.D.082 to free fouled airgun and GLORIA vehicle lines and were unable to continue with the survey because of the bad weather. Survey resumed 0621GMT J.D.083 and finally finished 0104GMT J.D.084. Arrived Woods Hole 130OGMT J.D.085. PERFORMANCE OF SCIENTIFIC EQUIPMENT GLORIA System. The equipment performed correctly throughout the cruise. However the Laser Replay System produced slightly asymmetric photographic prints. This assymmetry was approximately 1%. Survey data were lost when: A/ Sea conditions made it impractical to occupy the survey track lines or reduced the quality of the data to an unacceptable level. B/ The Gulf Stream reduced the theoretical propagation range and/or the ship's ability to maintain the correct speed over the ground. C/ Biological targets obscured the data. D/ The vehicle tow cable had to be changed after being damaged by bad weather. SRP System. Airguns. One of the airguns (No 1) failed when the top flange of the of the shuttle cracked. Airgun No 2 failed to seat properly until a new bottom liner was fitted. This resulted in the loss of several hours SRP data. Compressors. Compressor No 2 operated without fault. No 1 failed on three occasions due to the lst and 2nd stages being damaged and the brushes arcing on the slip rings of the electric motor. 3.5kHz High Resolution Profiler. The record was frequently noisy in a following sea. LSR. The Raytheon LSR was prone to false triggering and needed servicing frequently, also the drive to the storage spool was inadequate, making it necessary to manually wind the record onto the storage spool. Towed transducer. In the early part of the cruise the towed transducer was recovered because the record had become very noisy. As the tow cable had been damaged by a waterborne object it was necessary to replace this transducer. Precision Echo Sounder. Performed without fault throughout the cruise. Magnetometer. No faults reported.