Wireline Standard Data Processing
ODP logging contractor: LDEO-BRG
Well name: 852D
Leg:
138
Location:
East Pacific Rise (tropical NE Pacific)
Latitude:
5° 17.550' N
Longitude: 110° 4.537' W
Logging date: June, 1991
Bottom felt: 3871.5 mbrf (used for depth shift to sea floor)
Total penetration: 116 mbsf
Total core recovered: 230.6 m (105.8 %)
Logging Runs
Logging string 1: ACT/GST/NGT
Wireline
heave compensator was not used to counter ship heave.
Bottom-hole Assembly
The
following bottom-hole assembly depth is as it appears on the logs after depth
shift to the sea floor. As such, there might be a discrepancy with the original
depths given by the drillers onboard. Possible reasons for depth discrepancies
are ship heave and drill string and/or wireline stretch.
ACT/GST/NGT:
Bottom-hole assembly at ~ 49.5 mbsf.
Processing
Depth
shift: As only one logging run was
recorded no depth match between runs was necessary. The original logs have been
depth shifted 2.1 m downward to match a carbonate peak from core measurements
at 107 mbsf and then to the sea floor (- 3871.5 m).
Gamma-ray
processing: NGT data have been
processed to correct for borehole size and type of drilling fluid.
Quality Control
null
value=-999.25. This value generally appears in discrete core measurement files
and also it may replace recorded log values or results which are considered
invalid.
Data
recorded through bottom-hole assembly should be used qualitatively only because
of the attenuation on the incoming signal.
Additional
information about the logs can be found in the "Explanatory Notes" and Site
Chapter, ODP IR volume 138. For further questions about the logs, please
contact:
Cristina Broglia
Phone: 845-365-8343
Fax: 845-365-3182
E-mail: Cristina Broglia