Wireline Standard Data Processing

ODP logging contractor: LDEO-BRG

Hole: 1069A

Leg: 173

Location: Iberian Abyssal Plain (NE Atlantic)

Latitude: 40° 43.621' N

Longitude: 11° 46.632' W

Logging date: June, 1997

Bottom felt: 5086 mbrf

Total penetration: 959.3 mbsf

Total core recovered: 95.9 m (39.9 %)

Logging Runs

Logging string 1: DIT/ASP/HLDS/HNGS

Wireline heave compensator was used to counter ship heave.

Bottom-hole Assembly

The following bottom-hole assembly depths are as they appear on the logs after differential depth shift (see "Depth shift" section) and 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, use of wireline heave compensator, and drill string and/or wireline stretch.

DIT/APS/HLDS/HNGS: Bottom-hole assembly at ~101 mbsf.

Processing

Depth shift: Because only one logging pass was recorded, no differential depth shift was necessary. The original logs have been depth shifted to the sea floor (- 5087 m). This valued differs 1 meter from the "bottom felt" depth given by the drillers (see above).

Gamma-ray processing: HNGS data from the DIT/APS/HLDT/HNGS tool string were corrected in real-time during the recording.

High-resolution data: No high resolution data was recorded in Hole 1065A.

Quality Control

During the processing, quality control of the data is mainly performed by cross-correlation of all logging data. Large (>12") and/or irregular borehole affects most recordings, particularly those that require eccentralization (APS/HLDS) and a good contact with the borehole wall. The data of Hole 1069A is generally of good quality.

Data recorded through bottom-hole assembly, such as the HNGS data above 101 mbsf, should be used qualitatively only because of the attenuation on the incoming signal.

Hole diameter was recorded by the hydraulic caliper on the HLDS tool (LCAL).

Additional information about the logs can be found in the "Explanatory Notes" and Site Chapter, ODP IR volume 173. For further questions about the logs, please contact:

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