LWD Standard Data Processing

 

ODP logging contractor: LDEO-BRG

Hole: 1188B

Leg: 193

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 Runs

 

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. 

 

Processing

 

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.

 

Quality Control

 

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:

 

Cristina Broglia
Phone: 845-365-8343
Fax: 845-365-3182
E-mail: Cristina Broglia