Energy-resources map of the Circum-Pacific region, Pacific Basin sheet

Abstract

to the index maps and tables in these notes. Other principal investigators and sources of data are indicated in the references section on the map sheet and in the bilbliographic references that follow. Affiliations represent time of compilation. The Energy-Resources Map of the Circum-Pacific Region, Southwest Quadrant was compiled under the direction of Panel Chairman, R. W. Johnson and by W. David Palfreyman, both of the Australian Geological Survey Organisation (AGSO). Energy-resources data were compiled from a number of geoscience maps of various scales produced by AGSO, Australian State and Territorial government geoscience organizations, similar organizations in the southwest Pacific region, and various private companies and universities. BACKGROUND INFORMATION LAND AREAS The background data on land are generalized from the l:10,000,000-scale geologic maps of the four Quadrants. Significant tectonic and lithologic units have been combined into only seven divisions. The classification is designed to show the significance of host-rock units or terranes to the occurrence of energy resources. The background units are depicted in pale colors so as not to detract from the resource SOUTHWEST QUADRANT The geological background has been generalized from the Geologic Map of the Circum-Pacific Region, Southwest Quadrant (Palfreyman, 1988). Significant tectonic and lithological units have been combined to form seven major groups: Major sedimentary basins, platform deposits, and surficial deposits. These are generally thick deposits of sediment that show little to no deformation. They range in age from Proterozoic to Cenozoic. This area contains the vast majority of the coal, oil, gas, and oil shale deposits in the Southwest Quadrant region. Volcanic rocks. These range in age from Proterozoic to Cenozoic and are found throughout the Australian continent. They are especially concentrated along the convergent plate boundaries to the north and east of Australia. Areas of undivided igneous rocks, mixed volcanic and intrusive igneous rocks, confined to the Indonesian island of Sumatra are included in this category. Phanerozoic fold belts and deformed basinal deposits. These consist of belts of deformed and metamorphosed sedimentary and igneous-rocks and are concentrated in the east and south of the Australian continent, in the eastern part of the Papua New Guinea mainland, and in the South Island of New Zealand. Precambrian mobile zones and deformed platform cover deposits. These consist of belts of rocks similar to those of Phanerozoic age. They are found in the western and central parts of the Australian continent. Metamorphic complexes. Mostly Precambrian. These are areas of moderate-to high-grade metamorphic rocks that are located in central and western Australia. Intrusive igneous rocks. These range in age from Precambrian to Cenozoic and in composition from felsic to ultramafic. They are distributed widely throughout the map sheet area. TECTONIC SETTING The plate-tectonic framework of the Pacific basin is shown in figur...