Authors / CoAuthors
Vale, K.R. | Moss, F.J.
Abstract
Seismic reflection traverses were surveyed across the Perth Basin at Cookernup, W.A. These traverses were planned to find the thickness and dip of the Basin sediments adjacent to the Darling Scarp and to discover any faulting or folding within them; also to determine the applicability of the seismic method as a tool for both regional and detailed investigation in this area. Seismic refraction traverses were surveyed to help in the solution of problems encountered in the interpretation of the reflection cross-sections. The survey indicated a considerable thickness of sediments about 20,000 ft, at the eastern margin of the Basin near the Darling Scarp, and suggested tectonic structure that is not indicated in surface geology, The reflection traverses indicated that sediments (presumably Lower Palaeozoic or Precambrian) lying deep in the Perth Basin may continue underneath the Darling Scarp and abut the granitic gneisses etc. of the Western Australian Shield on an overthrust fault plane. The overthrust fault, if it exists, does not reach the surface, but is covered to a depth of possibly some few hundred feet by younger sediments and also by alluvium eroded from the Darling Scarp. Some reflection and refraction shooting was done in an attempt to test this and other hypotheses, but the results crc inconclusive. Gravity results strongly suggest a normal fault, and if normal faulting is the case, the reflections from beneath the outcropping basement are possibly derived from shear zones, Some probable 'reflected refractions' were also observed. There is scope for further seismic testing but it is considered that conclusive evidence could only be provided by drilling.
Product Type
dataset
eCat Id
76386
Contact for the resource
Custodian
Owner
Custodian
Cnr Jerrabomberra Ave and Hindmarsh Dr GPO Box 378
Canberra
ACT
2601
Australia
Keywords
- Australian and New Zealand Standard Research Classification (ANZSRC)
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- Seismology and Seismic Exploration
- ( {1} )
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- HVC_144637
- ( {1} )
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- Seismic Data seismic survey
- ( Theme )
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- seismic reflection
- ( Theme )
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- seismic refraction
- ( Theme )
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- petroleum exploration
- ( Theme )
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- geophysics
- ( Theme )
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- seismic velocity
- ( {1} )
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- AU-WA
- ( {1} )
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- Published_External
Publication Date
1962-01-01T00:00:00
Creation Date
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Purpose
Maintenance Information
asNeeded
Topic Category
geoscientificInformation
Series Information
Record
Lineage
The Cookernup area, about 75 miles miles south of Perth, lies in the Perth Basin which extends from Cape Leewin in the south to Geraldton in the north. Gravity work by the Bureau of Mineral Resources, Geology and Geophysics in the Perth Basin (Thyer & Everingham, 1956; and Neumann & Flavelle, in preparation) indicates a considerable thickness of sediments and shows steep Bouguer anomaly gradients in the vicinity of the Darling Scarp. During February and March 1955 a Bureau seismic party carried out surveys in the Gingin area, about 45 miles north of Perth, and in the Cookernup area, to verify conclusions drawn from the gravity results, and to continue the study of the Perth Basin l using the seismic reflection method. This was part of a proposal to use the seismic surveys to assist in determining the thickness of sediments and the structure of the Basin at several locations. The Bureau seismic party revisited the Perth Basin in 1956 to do surveys at Busselton and Rockingham; additional work was done at Cookernup in 1956.
Parent Information
Extents
[-33.25, -32.75, 115.5, 116.0]
Reference System
Spatial Resolution
Service Information
Associations
Source Information
Source data not available.