Auswahl der wissenschaftlichen Literatur zum Thema „Petroleum Australia Spectra“

A new exploration method has been developed using surface and aerial gamma‐ray spectral measurements in prospecting for petroleum in stratigraphic and structural traps. Formerly troublesome lithologic and environmental variables are suppressed by correcting potassium and uranium readings using a new process of thorium normalization. Normalized potassium shows characteristic low concentrations above petroleum deposits. Normalized uranium shows higher values than normalized potassium over petroleum and generally lower values elsewhere. We attribute these anomalies to effects of microbial consumption of microseeping light hydrocarbons. Studies of National Uranium Resource Evaluation (NURE) Program aerial, gamma‐ray, spectral data covering portions of six states have shown characteristic normalized potassium and uranium anomalies above 72.7 percent of 706 oil and gas fields. Additionally, an average of 27 similar untested anomalies were found for each 1000 square mi (2600 square km) covered. Similar aerial gamma‐ray spectral data are available over large portions of potential petroleum areas of the U.S. including Alaska and Australia. Preliminary tests in two basins in Australia showed positive correlation between radiometrically favorable areas and known oil and gas regions. Ground‐based, gamma‐ray, spectral measurements found the same types of potassium and uranium anomalies over all twelve fields evaluated. Since 1988, our research of surface radiometric data coupled with soil gas hydrocarbon and soil magnetic susceptibility surveys has resulted in discovery of four oil and gas fields in Concho County, Texas.

The use of wireline and core spectral gamma data as a tool for defining clay types and mineral assemblages in the subsurface environment has been widely used for many years within the petroleum industry. However, the qualitative use of radiometric data for interpreting rock types as used with airborne surveys in the mineral industry has not undergone detailed assessment as a well correlation tool.Applying the principles of qualitative airborne radiometric interpretation to the assessment of wireline spectral gamma ray data has proved extremely useful as a well correlation tool in the Carnarvon Basin of Western Australia. Data is presented from the Stag Field detailing the application of the technique as an effective fieldwide correlation tool. The sandstone reservoirs exhibit mineralogical variation and individual sand packages can be discontinuous. However, the major shale packages are laterally continuous and individual shales show remarkable character consistency over several kilometres. Such character continuity has proved a valuable correlation tool for confirming and refining the stratigraphic packages observed in the Cretaceous section of Stag.Success on the Stag Field led to application of the technique for regional correlations on the Enderby Terrace. The results of regional work show that correlations still hold when the technique is applied to correlations of over 70 km even though some lateral variation due to provenance and depositional environment impact on clay types was evident. Hence this qualitative approach of wireline log evaluation has proved an effective and valuable correlation tool.

The vast and mostly onshore Canning Basin—with an area of approximately 595,000 m2—is the least explored onshore sedimentary basin in Australia. As part of the petroleum system assessment carried out by WA DMP, more than 160 samples were investigated from eight wells in the onshore Canning Basin—they are: Acacia-1 Dodonea-1 Dodonea-2 Lake Hevern-1 Looma-1 White Hill-1 Wilson Cliffs-1 Yulleroo-1. Fluid inclusion and quantitative fluorescence techniques developed by CSIRO were used, including: The grains containing oil inclusions (GOITM) technique; The quantitative grain fluorescence (QGF) technique; QGF on extracts (QGF-E); and, the total scanning fluorescence (TSF) technique. The results reveal a widespread occurrence of hydrocarbon shows in the reservoir intervals investigated—7–8 wells showed evidence of oil migration and/or accumulations often occurring at multiple depth intervals. In White Hill-1, elevated QGF and QGF-E responses were recorded in the sandy units in a depth interval of more than 500 m in the Fairfield Group. A residual or palaeo oil column of >20 m gross height at 1,655 m was apparent from the QGF and QGF-E depth profiles—and GOI and TSF data. Oil inclusions from the Fairfield Group in White Hill-1 show spectral signature typical of thermally mature and light-medium API gravity. The TSF results also indicate the presence of some condensate species, as well as relatively heavy and possibly bio-degraded oils. The new fluid inclusion and fluorescence data provide direct evidence of an active petroleum system in the Canning Basin at multiple reservoir intervals, which may be of local significant quantity.

The Ceduna Sub-basin in Australia’s southern margin offers an untapped opportunity for significant petroleum resource as part of the global exploration portfolio. Analogous to the prolific Niger delta in both size and structural style, this highly-extensional province contains up to 15 km of largely untested post-rift sediments including two widespread Late Cretaceous deltas linked to world-class oil-prone marine Cretaceous source rocks. Regional interpretation of legacy 2D seismic across the Bight Basin brings the sheer scale and structural complexity of this giant Cretaceous depocentre into perspective, but it is only through the detailed analysis of 8001 km2 of dual-sensor towed streamer 3D seismic that its true potential can be quantified. Rigorous phase and amplitude AVO QC of the pre-stack information, coupled with optimised velocity models fed into the depth migration sequence, have ensured amplitude fidelity and phase stability across all offset ranges. This has enabled a systematic and robust exploration workflow of AVO analysis and pre-stack inversion despite limited well data. Numerous dual-sensor case studies have nevertheless demonstrated these Relative Acoustic Impedance and Vp/Vs volumes to be reliably robust for prospect de-risking because of the extended low frequency bandwidth. Frontier screening supported by a partially-automated high-resolution stratigraphic framework has led to the identification of numerous prospects at multiple stratigraphic levels across the survey area. This includes isolation of laterally extensive and vertically amalgamated fan-like structures within the shallow Hammerhead delta using horizon-constrained high-definition spectral decomposition, and the extraction of potential AVO anomalies within the deeper structurally-controlled White Pointer sands draped across large gravity-driven listric growth faults.

Cekungan Akimeugah terletak pada paparan Laut Arafura yang merupakan bagian dari passive margin yang berasosiasi dengan cekungan di kontinen Australia yang sudah memproduksi hidrokarbon seperti cekungan Bonaparte, Carnavon dan cekungan Canning. Secara tektonik cekungan ini berkembang akibat pertemuan lempeng Australia dengan Pasifik sehingga menyebabkan munculnya struktur lipatan, tinggian, rendahan dan patahan. Salah satu metoda geofisika yang dapat digunakan untuk mengetahui struktur geologi bawah permukaan adalah metoda gayaberat. Tujuan dari penelitian ini adalah untuk mengidentifikasi struktur geologi bawah permukaan, mendelineasi sub-cekungan sedimen serta memperkirakan ketebalan sedimen di Cekungan Akimeugah bagian selatan. Analisis data yang digunakan yaitu analisis spektrum, filter optimum upward continuation serta pemodelan inversi 3D. Hasil analisis spektral menunjukkan bahwa tebal batuan sedimen rata rata di daerah penelitian adalah sekitar 3.6 Km. Ketinggian optimum yang digunakan pada filter optimum upward continuation yaitu pada ketinggian 6000 m dan menghasilkan anomali regional serta residual. Sub-cekungan yang didelineasi dari analisis data gayaberat adalah sebanyak 7 sub-cekungan sedimen, dimana pola struktur yang teridentifikasi yaitu berupa tinggian, graben dan patahan. Hasil pemodelan 3D menunjukkan bahwa batuan dasar cekungan berupa batuan metamorfik dengan nilai rapat massa 2.7 gr/cc. Kemudian secara berurutan dari bawah ke atas diendapkan batuan sedimen dari kelompok Aifam yang berumur Paleozoikum dengan nilai densitas 2.6 gr/cc, kemudian di atasnya lagi adalah batuan sedimen kelompok Kemblengan yang berumur Mesozoikum dengan nilai rapat massa 2.5 gr/cc, dan yang paling atas adalah batuan sedimen tersier kelompok batugamping Nugini dengan nilai rapat massa 2.4 gr/cc dan Formasi Buru dengan nilai rapat massa 2.2 gr/cc.. Hasil analisis model bawah permukaan menunjukkan bahwa berdasarkan pola graben dan tinggian, Cekungan Akimeugah bagian selatan cukup potensial untuk berkembangnya petroleum system seperti cekungan di Australia yang sudah berproduksi hidrokarbon.Kata Kunci : Gayaberat, spektral analisis, filter optimum upward continuation, pemodelan 3D inversi, Cekungan Akimeugah selatan, Papua.The Akimeugah Basin is located on the Arafura Shelf which is part of the passive margin associated with basins of Australian continent that have produced hydrocarbons such as the Bonaparte basin, Carnarvon and the Canning basins. Tectonically this basin develops due to the collision between the Australian and the Pacific plates, resulting folds, highs, lows and faults. One of the geophysical methods that can be used to determine the subsurface geological structure is the gravity method. The purposes of this study are to identify subsurface geological structures, delineating sediment sub-basin and to estimate sediment thickness in the southern Akimeugah basin. Data analysis used are spectrum analysis, optimum upward continuation filters and 3D inversion modeling.. The spectral analysis results show that the average thickness of the sedimentary rock in the study area is about 3.6 Km. Optimum height that used at the optimum upward contiuation filter was at an altitude 6000 m and resulting regional and residual anomaly. The delineated sub-basin obtained from gravity data analysis is as many as 7 sediment sub-basins, where the identified structural pattern is in the form of high, graben and fault. The 3D modeling results show that the basement of the basin is of a metamorphic rock with a mass density value of 2.7 gr/cc. Then sequentially from the lowest, sedimentary rocks from the Aifam group of Paleozoic were deposited with a density value of 2.6 gr/cc, hereafter is sediment group of Kemblengan of Mesozoic with mass density values of 2.5 gr/cc, and at the top is a Tertiary sedimentary rock, limestone Nugini group with a mass density value of 2.4 gr/cc and Buru Formation with density value 2.2 gr/cc. The results of the subsurface model analysis show that based on a graben and high pattern, the southern Akimeugah basin is potential for the development of petroleum systems such as the basins those already produce hydrocarbons in Australia.Keywords: gravity, spectral analysis, optimum upward continuation filter, modeling 3D inversion, southern Akimeugah Basin, Papua.

"September 2002" Includes bibliographical references (leaves 200-209) Outlines an evaluation procedure for stratigraphic trap exploration by employing sequence stratigraphy, 3D seismic data visualisation and quantitative risk analysis with case studies in an actual exploration basin.

"September 2002"
Includes bibliographical references (leaves 200-209)
xi, 209, [51] leaves : ill. (chiefly col.), maps, plates (chiefly col.) ; 30 cm.
Outlines an evaluation procedure for stratigraphic trap exploration by employing sequence stratigraphy, 3D seismic data visualisation and quantitative risk analysis with case studies in an actual exploration basin.
Thesis (Ph.D.)--University of Adelaide, National Centre for Petroleum Geology and Geophysics, 2002