These notes deal with a brief experimental seismic survey undertaken by the Bureau of Mineral Resources for the Victoria Railways. The object of the survey was to determine whether the seismic refraction method was suitable for subsurface exploration in the area between Dynon and Footscray Roads, West Melbourne. The information desired by the Railways was concerned with the existence or otherwise of a "foundation" rock capable of supporting constructions associated with railway sidings and marshalling yards. Records of seismic refractions were obtained along three traverses.

Reflection and refraction seismic work was done in 1960 to complete a reconnaissance survey which was commenced in 1959 across the northern part of the Surat Basin. A reconnaissance line now extends in an easterly direction from 30 miles west of Surat to Jondaryan, and this line is also tied to the geologically well-known Roma area. Two good marker horizons have been established in the seismic work - one a strong reflector and the other a refractor in which the velocity averages 19,000 ft/sec and which may represent basement. A deep trough of sediments, possibly 20,000 ft thick at Meandarra, exists between Surat and Tara, and there is a large uplift west of Tara. The eastern margin of this large trough is 12 miles east of Tara, but sediments about 4000 ft thick probably continue to the east, at least as far as Jondaryan.

Near surface information can be obtained from regional seismic data showing the weathering and layering properties, as well as dipping bedrock structures. Hard limestone layers in the near surface overlying soft sediments make complex refracted arrivals and refraction statics are difficult to define and in some cases it is best not to apply refraction statics to the reflection data. For some of the data in this survey surface sand dunes over 10 m high caused significant time delays for reflected data and refraction statics were essential prior to further reflection processing. Numerous refraction models were produced and tested along the data. Refraction models provided useful information about layering in the near surface, and helped with the seismic processing. The refractor models also indicated the possible presence of ground water. In some places the refracted arrivals changed polarity indicating either change in thickness or hardness of the limestone at the near surface overlying slower unconsolidated sediments. These regions sometimes correlated with diminished reflections. Dip moveout (DMO) correction was essential to improve near surface steep dipping structures.

The Geoscience Australia Onshore Seismic GIS layer is layer showing the locations of Onshore Seismic Survyes carried out by Geoscience Australia and it's predecessors, Australian Geological Survey Organisation (AGSO) and the Bureau of Mineral Resources (BMR). The layer contains URL link to free downloadable data. The data includes processed data in SEGY format. The metadata includes acquisition reports, processing reports, processed images and so on. The data acquisition was carried out in Australia from 1949 to present by Geoscience Australia and various partners such as State and Geologcial Survey Organisations. The set of reflection and refraction data comprises over 12,000 km of coverage, and provides an insight into the variations in crustal architecture in the varied geological domains.

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.

A seismic reflection survey was made to the south-west, south and east of the Poole Range Structure, Kimberley Division, W.A. as an extension of a previous seismic survey. The results obtained confirm the surface information and show the existence of an anticlinal structure l the axis of which plunges to the east and whose axial plane probably dips to the south. A total thickness of sediments of the order of 20,000 feet is shown. Some slight evidence of deep faulting down to 10,000 feet was recorded, but is not conclusive. Insufficient evidence was obtained to select a site for a test bore, but further seismic work is not recommended at present.

The Bureau of Mineral Resources seismic party carried out a seismic survey in the Bonaparte Gulf area of north-western Australia between 16th June and 13th October, 1956. The initial objects of the survey were to obtain regional information on the thickness of the sedimentary rocks and on the tectonics of the Bonaparte Gulf Basin, and to establish the applicability of the seismic method in the area. During the course of the survey the party was directed to transfer its attentions to obtaining some detailed information on the Spirit Hill Anticline. This latter work was carried out in response to an application by Westralian Oil Pty. Ltd., which was anxious to select sites for a test boring programme. The seismic results indicate a maximum thickness of sediments of about 20,000 feet in the Carlton Basin and 14,000 feet in the Burt Range Basin. The rocks in both these basins have been folded to a considerable extent and the reflections suggest unconformities within both basins. The seismic reflection method proved successful in indicating geological structure at depth in most of the areas tested.

A seismic survey extending over the Poole Range and Price's Creek areas and the Pinnacle Fault, near the north-eastern boundary of the Fitzroy Basin was corducted during the winter of 1953. The Poole Range Dome has been mapped in outcropping rocks of Permian age, but its western closure is not certain. It is at the south-eastern end of a line of anticlinal folding which includes the St. George Range Dome and Nerrima Dome. The target beds for an oil test bore would be the Devonian and/or Ordovician rocks, which crop out on the north-eastern side of the Pinracle Fault, and over which the Permian rocks of the Poole Range are believed to lie unconformably. The seismic results indicate a thick section of sediments on the south-western side of the Pinnacle Fault and show a fair degree of conformity between shallow and deep reflections on the northern flank of the dome. Further investigatioll was made in 1954 around the flanks of the dome to determine whether or not the domal structure persists at depth, but the interpretation of the results of the 1954 survey is not yet complete. The Ordovician rocks on tbe north-eastern side of the Pinnacle fault are shown to have a probable unexposed thickness of about 900 feet.

<p>This is a Joint Research Project of a seismic test survey using dynamite as a seismic source in the Gippsland Basin between South Australian Gas Company (SAGASCO) and Geoscience Australia. This survey wad conducted by using the GA Sercel SN368 seismic 120 channel data acquisition system, two drilling rigs and seismic crew. The primary objective of the seismic test survey was to test whether by using dynamite as the seismic energy source, seismic reflection events could be recorded from geological horizons below the base of the Latrobe Valley Group. Processing of the seismic data revealed that using explosives as a seismic source also had difficulty in resolving seismic reflection events below the Labtrobe Valley Group sediments. In places multiple reflection events due to the coal beds within the Latrobe Valley Group are intermixed with primary reflections making interpretation of deeper reflection events difficult or impossible. However long offsets recordings highlighted a significant first break refraction event at far offset distances, which from preliminary interpretations is related to the base of the Latrobe Valley Group or top of Strzelecki Group. To resolve the thickness of Strzelecki Group sediments, the recording of first break refraction events using long offset walkaway spreads (offsets in the 6 to 8 km range) maybe a technique to test in future seismic surveys.<p><b>Raw data for this survey are available on request from clientservices@ga.gov.au - Quote eCat# 74946</b>

A seismic survey was made in the.Ooraminna area of the Amadus Basin 9 Northern Territory 9 by a seismic party of the Bureau of Mineral Resources 9 Geology and Geophysics 9 between 6th July and ,29th August 1962. Reflection traverses were recorded between Deep Well and Alice Springs and across the culmination of the Ooraminna Anticline l and a refraction depth probe was recorded on the crest of the Ooraminna Anticline. The purpose of the survey was to obtain information on the structure of the Basin in the eastern part of the Missionary Plain, and on the structure of the Ooraminna. The Basin was shown to be generally synclinal between Deep Well and Alice Springs with a maximum sediment thickness Of 20,000 feet north of the Ooraminna Anticline. Seismic evidence suggested that the uplift at Deep Well and the Ooraminna Anticline have resulted from thickening in a deep formation, which has been tentatively identified as the Bitter Springs Formation. The survey was unsuccessful in relating reflectors in the crosssections with outcropping formations in the MacDonnell Ranges and on the Ooraminna Anticline.