![\"\"](\"http:\/\/trilobite.solutions\/map\/wp-content\/uploads\/2018\/09\/drylakeriver-300x300.png\")
<\/p>\nThe following screenshots illustrate the main features of the map.<\/p>\n
<\/p>\n
A lake or river that is dry most of the time<\/em>.\u00a0 The blue striping indicates that the lake or river is usually dry, and will generally only have water after significant rain.<\/p>\n All Cenozoic and Quaternary sediments.<\/em>\u00a0 Australia is a very eroded continent, thus a large part of its surface is covered with sediment.\u00a0 For example, 42% of South Australia is covered by sand plains and dunes.\u00a0 This category includes a large number of other sediment types including river, lake and estuarine deposits, soft limestones, colluvium (deposits that have slid down a slope), black soil plains, bauxite, silcrete, laterite, peat and glacial deposits.\u00a0 Sand dunes are common in dry country and distinguished by the patterning shown below.<\/p>\n Cenozoic and quaternary volcanics, mainly basalts<\/em> are indicated with a rusty colour.\u00a0 These are only found in Eastern Australia and are recent enough that you can often make out the shape of the original volcano.\u00a0 The screenshot above shows the remains of an old volcano and the caldera.\u00a0 The basalt soils formed from these rocks include prime agricultural land – eg. Don and Sassafras in Tasmania, the Darling Downs in Queensland, and the Liverpool Plains of NSW.<\/p>\n Pink colouring is used to indicate granite<\/em>.\u00a0 This is a rock composed mainly of light coloured quartz and feldspar crystals and forms distinctive rounded outcrops.\u00a0 The screenshot above is of the Karlu Karlu\u00a0 (Devils Marbles) Conservation Reserve<\/a>.<\/p>\n The grey colouring indicates paleozoic and mesozoic<\/em> sedimentary rocks, volcanics and metamorphic rocks.\u00a0 Fossils can be found in the sedimentary rocks, in the right places.\u00a0 Usually it is best to look in shales and siltstones, rather than sandstones or conglomerates.<\/p>\n The brown colouring indicates ancient archean and proterozoic<\/em>\u00a0sedimentary rocks, volcanics and metamorphic rocks.\u00a0 Because of their extreme age, it is very rare to find fossils, but there are a very small number of exceptions, for example the famous Ediacaran fossils of South Australia.<\/p>\n Note that the geology boundaries are not absolutely accurate. With pre-GPS data, the boundaries can be out by as much as a kilometre, although boundaries are generally accurate to 100 metres or better.<\/p>\n","protected":false},"excerpt":{"rendered":" The following screenshots illustrate the main features of the map. A lake or river that is dry most of the time.\u00a0 The blue striping indicates that the lake or river is usually dry, and will generally only have water after significant rain. All Cenozoic and Quaternary sediments.\u00a0 Australia is a very eroded continent, thus a … <\/p>\n![\"\"](\"http:\/\/trilobite.solutions\/map\/wp-content\/uploads\/2018\/09\/sediments-300x300.png\")
<\/p>\n![\"\"](\"http:\/\/trilobite.solutions\/map\/wp-content\/uploads\/2018\/09\/sanddunes-300x300.png\")
<\/p>\n![\"\"](\"http:\/\/trilobite.solutions\/map\/wp-content\/uploads\/2018\/09\/volcanics-300x300.png\")
<\/p>\n![\"\"](\"http:\/\/trilobite.solutions\/map\/wp-content\/uploads\/2018\/09\/granite-300x300.png\")
<\/p>\n![\"\"](\"http:\/\/trilobite.solutions\/map\/wp-content\/uploads\/2018\/09\/oldrocks-300x300.png\")
<\/p>\n