Sonic Waveform Data
Coring and logging operator: Texas A&M University
Hole: U1445A
Expedition: 353
Location: Mahanadi Basin (NW tropical Indian Ocean)
Latitude: 17° 44.7217' N
Longitude: 84° 47.2518' E
Logging date: January 6, 2015
Sea floor depth (driller's): 2513.1 m DRF
Sea floor depth (logger's): 2509 m WRF
Total penetration (APC coring): 3185.7 m DRF (672.6 m DSF)
Total core recovered: 664.4 m (99.1 % of cored section)
Oldest sediment recovered: Late Miocene (~6 Ma)
Lithologies: Biosilica-rich clay and sandy turbidites.
TOOL USED: DSI (Dipole Sonic Imager)
Recording mode: Monopole P&S and Cross-Dipole (inline and crossline).
Remarks about the recording: none.
MONOPOLE P&S MODE: measures compressional and hard-rock shear slowness. The monopole transmitter is excited by a high-frequency pulse, which reproduces conditions similar to previous sonic tools.
CROSS-DIPOLE MODE: uses alternate firings of upper and lower dipole transmitter, thus allowing acquisition of orthogonally polarized data for anisotropy studies.
Acoustic data are recorded in DLIS format. Each of the eight waveforms generally consists of 512 samples, each recorded every 10 (monopole P&S) and 40 microsec (dipolemodes), at depth intervals of 15.24 cm (6 inches).The original data in DLIS format is first loaded on a Sun system using GeoFrame software. The packed waveform data files are run through a GeoFrame module that applies a gain correction and then converted into ASCII and finally binary format.
Number of columns: 4097 (monopole)/1025 (cross dipole)
Number of rows (downlog): 2639 (monopole)/2640 (cross dipole)
Number of rows (main): 2416 (monopole)/2417 (cross dipole)
Number of rows (repeat):2125 (monopole)/2126 (cross dipole)
The following files have been loaded:
DSI from FMS/DSI/GPIT/EDTC-B/HNGS (Downlog, drill pipe at 84 m WSF)
353-U1445A_mono_d.bin: 83-485 m WSF
353-U1445A_cd_ldip_cl_d.bin: 83-485 m WSF
353-U1445A_cd_ldip_il_d.bin: 83-485 m WSF
353-U1445A_cd_udip_cl_d.bin: 83-485 m WSF
353-U1445A_cd_udip_il_d.bin: 83-485m WSF
DSI from FMS/DSI/GPIT/EDTC-B/HNGS(Main run, drill pipe at 84 m WSF)
353-U1445A_mono_main.bin: 83-451 m WSF
353-U1445A_cd_ldip_cl_main.bin:83-451 m WSF
353-U1445A_cd_ldip_il_main.bin: 83-451 m WSF
353-U1445A_cd_udip_cl_main.bin: 83-451 m WSF
353-U1445A_cd_udip_il_main.bin: 83-451 m WSF
DSI from FMS/DSI/GPIT/EDTC-B/HNGS (Repeat run, recorded open hole)
353-U1445A_mono_rep.bin: 127-450 m WSF
353-U1445A_cd_ldip_cl_rep.bin: 127-450 m WSF
353-U1445A_cd_ldip_il_rep.bin: 127-450 m WSF
353-U1445A_cd_udip_cl_rep.bin: 127-450 m WSF
353-U1445A_cd_udip_il_rep.bin: 127-450 m WSF
The sonic waveform files are depth-shifted to the seafloor ( m) but they are not depth-matched to the reference run. Please refer to the 'depth_matches' folder in the hole index page for the depth-matching values and to the "DEPTH SHIFT" section in the standard processing notes for further information.
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 353.