LWD Standard Data Processing
ODP logging contractor: LDEO-BRG
Location: Manus Basin (Bismarck Sea)
Latitude: 3°43.698' S
Longitude: 151°40.200' E
Logging date: November 25, 2000
Bottom felt: 1653 mbrf (by LWD gamma ray)
Total penetration: 72 mbsf
Total core recovered: n/a (LWD hole)
Logging string: RAB LWD (resistivity image, resistivity, gamma ray).
The plan was to run LWD to 75 mbsf. LWD was stopped just short of this depth when the penetration rate slowed considerably.
Depth shift: The logs were shifted to the sea floor (-1653 m). The sea floor depth was determined by the step in gamma ray and resistivity values at the sediment-water interface.
null value=-999.25. This value generally replaces recorded log values or results that are considered invalid.
The LWD tool used had a smaller diameter than the bit. This resulted in the shallow penetration resistivity measurement being lower than the medium and deep penetration measurements. The deep penetration measurement should be preferred.
Additional information about the logs can be found in the "Explanatory Notes" and Site Chapter, ODP Leg 193 IR volume. For further questions about the logs, please contact:
E-mail: Cristina Broglia