IEDA: Marine Geoscience Data System Integrated Earth Data Applications homepage

BSR Nankai ew9907

Search By Project (Cruise)

Seismic Project Information RC2613

This 1985 R/V Robert D. Conrad survey was the second of three legs (see RC2612 and RC2614) of the 1985 China Margin Project, a marine geophysical investigation of the passive continental margin along the northern side of the South China Sea between Taiwan and Hai-Nan Tao. Leg 2613 was the second leg of two-ship SP/CDP seismic data acquisition. The first leg (RC2612)acquired two-ship seismic data along a transect across the margin at roughly 117.5 deg E. This leg acquired two-ship data along a similar transect across the margin at about 113 deg E. The cooperating ship during both legs was the R/V Ocean-4 (Haiyang-4), from the second Marine Geology Brigade, People's Republic of China, based in Guangzhou (Canton). The objectives were to conduct wide-angle CDP, deep penetration seismic measurements and to shoot ESP profiles along two transects across the northern continental margin of the South China Sea basin.

CDP 624, 626, 628, 630, 632, 634, 636, 637
ESP 625, 627, 629, 631, 633, 635
CC: Conrad recorded Conrad shots
OO: Ocean 4 recorded Ocean 4 shots.
For ESP lines Conrad recorded the ESP shot by Ocean 4 and the Ocean 4 recorded their own shots as a reflection line.
All esp line OO stacks have a one min shot interval.
All cdp line CC stacks have a 20 sec shot interval.

For OO stacks:
There are no cdpnav files for the OO stacks, we have no navigation from the Ocean 4. The quality of the OO stacks was poor. They were processed because they provided the only cdp data along the ESP lines.

CDP gathering was done assuming a constant shot distance of 150 meters. All OO stacks are of the Ocean 4 recording their shots during ESPs with the Conrad recording the ESP. For all ESPs except line 622 the two ships start ~ 100 km apart and sailed toward each other, passed each other as close as was safe and continued on again for another ~100 km. The assumption is that the Ocean 4 track was roughly the inverse of the Conrad track.

John B. Diebold
Stephen Lewis
Chief Scientists:
Dennis Hayes (NSF 8415973)
John W. Ladd (NSF 8415973)
Stephen Lewis (NSF 8415973)
John B. Diebold (NSF 8415973)
Principal Investigators:
Lamont-Doherty Earth Observatory
Ministry of Geology, People's Republic of China
Data Originating Institutions:
People's Republic of China
Funding Agencies:
Unrestricted access.
Seismic Data Types Acquired:
Seismic Data Classes at UTIG:
Seismic Data Types at UTIG:
Other related data for this program at LDEO:

Click on arrows below to show details.