Comparison of sonobuoy and sonic probe measurements with drilling results

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doi: 10.2973/dsdp.proc.29.141.1975
Author(s): Houtz, R. E.
Author Affiliation(s): Primary:
Lamont-Doherty Geol. Obs., Palisades, N.Y., United States
Volume Title: Initial Reports of the Deep Sea Drilling Project
Source: Initial Reports of the Deep Sea Drilling Project, Vol.29, p.1123-1132. Publisher: Texas A & M University, Ocean Drilling Program, College Station, TX, United States. ISSN: 0080-8334 CODEN: IDSDA6
Note: In English. Lamont-Doherty Geol. Obs. Contr. No. 2026; illus. incl. table, sketch map
Summary: Regional velocity functions based on sonobuoy solutions were used to predict four layer thicknesses at three Leg 29 drill sites with an average error of 7%. A computer program (based on an improved RS-R1 technique) to determine velocity gradients from individual sonobuoy records was applied successfully to data from the New Zealand Plateau and central Tasmanian Sea. Direct comparisons with sonobuoy solutions at or very near drill sites indicated no significant difference between observed and computed data. Predicted velocity functions and observed mean velocities (based on well-identified reflectors) were compared with Leg 29 sonic probe data. It was observed that the coring process had very little effect on the sonic velocity of sediments taken from below an overburden of about 300 m thickness, but that sonic velocities measured in sediments with less overburden were much too low. The largest discrepancies occurred in material taken from zones with 200 m of overburden, where the measured values averaged 180 m/sec less than the predicted values.
Year of Publication: 1975
Research Program: DSDP Deep Sea Drilling Project
Key Words: 20 Geophysics, Applied; Acoustical methods; Comparison; Deep Dea Drilling Project; Deep Sea Drilling Project; Elastic waves; Geophysical methods; Geophysical surveys; Instruments; Laboratory studies; Leg 29; Marine; Marine geology; Pacific Ocean; Physical properties; Sediments; Sonic probes; Sonobuoys; South Pacific; Southwest; Southwest Pacific; Surveys; Tasman Sea; Velocity; West Pacific
Coordinates: S570000 S400000 E1770000 E1430000
Record ID: 1976016994
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data supplied by Institute of Geological and Nuclear Sciences Limited (GNS Science), Lower Hutt, New Zealand