Physical Characteristics of The Drainages of The Yilgarn Block, South Western Australia

[摘要] The Yilgarn Block of Western Australia is composed principally ofArchaean intrusive granitoid rocks with metamorphosed igneous andsedimentary assemblages, or greenstone belts, which are north or northwest trending. To the north and east the granitic terrain is deeplyweathered to produce large subdued areas of flat sandplain usuallyoverlying kaolinized •pallid zones•, whereas to the south and west reliefis more marked, bedrock is closer to the surface and thinner •pallidzones• frequently occur with a ferricrete or laterite capping near thepresent land surface. Whilst the underlying geology over the extent ofthe Yilgarn Block is very similar, these subtle but distinguishabledifferences in the weathering patterns from north-east to south-west havebeen influenced by, and in turn have had a marked effect on the hydrogeology and hydrogeochemistry of the widespread, generally saline, shallow aquifers....

[发布机构] CSIRO

[学科分类] 地球科学(综合)