Borehole Seismic Data
Science operator: Texas A&M University
Hole: U1566A
Expedition: 396
Location: Kolga High (North Eastern Atlantic Ocean)
Latitude: 64° 57.8869' N
Longitude: 2° 43.7533' E
Logging date: August 20, 2021
Sea floor depth (driller's): 2110.3 m DRF
Sea floor depth (logger's): 2113 m WRF
Total penetration: 2292 m DRF (181.7 m DSF)
Total core recovered: 100.50 m (55.2 % of cored section)
Oldest sediment recovered: Quaternary
Lithology: Clay, silt and sand; aphyric basalts.
SEISMIC TOOL USED:VSI (Versatile Seismic Imager)
The logging data was recorded by Schlumberger in LDF/DLIS format. All processing, including first arrival picking and stacking, was performed by Schlumberger during Expedition 396. The data was then converted into SEGY format at LDEO, using code developed in house.
As per shipboard party's request, the stations were recorded at 10 m intervals from 2250 m WRF (137 m WSF) to the sea floor. The stations at 2170 (57 mWSF) and 2160 m WRF (47 m WSF) were skipped because they tool would be partially inside the drill pipe (located at ~ 46 m WSF) while anchored, which would result in caliper arm damage. Also, the last two stations inside the drillpipe were skipped as it was observed that the previous ones inside the pipe showed no signs of coupling between the pipe and the formation, which resulted in useless data. Overall, 11 stations were acquired.
Stacks are generally calculated with at least nine good traces.
All the data in the SEGY files are sorted shot by shot (i.e. chronologically).
Additional information about the drilling and logging operations can be found in the Operations and Downhole Measurements sections of the expedition report, Proceedings of the International Ocean Discovery Program, Expedition 396.
For any question about the data or about the LogDB database, please contact LogDB support: logdb@ldeo.columbia.edu.