Borehole Seismic Data

ODP logging contractor: LDEO-BRG

Hole: 1251H

Leg: 204

Location: Hydrate Ridge - Cascadia Margin (NE Pacific)

Latitude: 44° 34.2089' N

Longitude: 125° 4.4514' W

Logging date: August 17-18, 2002

Water depth (as seen on logs): 1219.5 mbrf

Total penetration: 445 mbsf

Total core recovered: no cores taken in this hole

TOOL USED: WST3 (3-Component Well Seismic Tool.

The logging data was recorded by Schlumberger in DLIS format. Zero-offset VSP stations were taken with the WST-3 at 7.5 m intervals, about half of which yielded reasonable quality results. Walk-away VSP surveys along E-W and N-S lines were made with a station at 100 mbsf.

All processing, including first arrival picking and stacking, was performed by Schlumberger during Leg 204. The data was then converted into SEGY format at the Borehole Research Group of the Lamont-Doherty Earth Observatory, using the SEGY Save module in GeoFrame.

Stacks are generally calculated with at least seven good traces.

All the data in the SEGY files are sorted shot by shot (i.e. chronologically).

Gilles Guerin

Phone: 845-365-8671

Fax: 845-365-3182

E-mail: Gilles Guerin

Cristina Broglia

Phone: 845-365-8343

Fax: 845-365-3182

E-mail: Cristina Broglia