The Wianamatta Group is a geological feature of the Sydney Basin, New South Wales, Australia. [1] The Wianamatta Group directly overlies the older (but still Triassic in age) Hawkesbury sandstone. The shale formations generally comprise fine grained sedimentary rocks such as shales and laminites as well as less common sandstone units.
The Wianamatta Group is made up of the following units (listed in stratigraphic order):
The Wianamatta Group is the youngest geological layer member of the Sydney Basin, and therefore lies at the highest point as the highest layer member. It was deposited in connection with a large river delta, which shifted over time from west to east. This is evidenced by the sequence of strata, which clearly show the transition from marine deposits in front of the delta to deposits on land: Ashfield shale was formed from clayey marine sediments. The subsequent Minchinbury Sandstone emerged from beach - Nehrungs Islands. The Bringelly shale became alluvial in a marshy plain deposited on the delta, meandered through the rivers, and deposited sand at various locations, each of which was narrowly defined, which later solidified into sandstone. [2]
Today's weathering of the surface of the existing claystone produces abundant clay, which leads to the formation of clay soils with low water permeability, as they occur, for example, on the Cumberland Plain widespread. Here are Podsol floors widespread that swell when supplying water and shrink during drying.
Over the pitches of the Wianamatta Group, water-bearing layers can form. Deep and large clay deposits of this formation are able to collect groundwater; however, if they are at or near the surface, salted dry land may form as the water evaporates. The quality of the groundwater over the pitches can be good, so that drinkable water occurs, or it can be very saline and thus not potable. The lower groundwater resources in the Wianamatta Group rocks are generally less saline than the near-surface occurrences. [3]
Wianamatta is spelled according to the way it sounded when spoken by the original Aboriginal people when questioned by the Rev. William Branwhite Clarke. Any reference to any other spelling sourced in the "trove" article in the Sydney Morning Herald is a typographical error.
The Wianamatta Group has been inferred to represent a cycle of basin infilling associated with the migration of a large delta front from west to east. The Ashfield Shale was deposited in a low energy marine environment and preserves laminated silty sediments. The Minchinbury Sandstone comprises a set of sandy barrier islands at the former shoreline. The Bringelly Shale was deposited in a swampy alluvial plain with meandering streams flowing from the west forming discontinuous beds of sandstone. [2]
Weathering of the shale units produces a rich clayey soil, often with poor drainage, such as that in the Cumberland Plain. [3] These clay soils are recognised as being reactive with appreciable Shrink-swell capacity.
Low-lying areas where groundwater is close to the surface are also susceptible to dryland salinity. Groundwater quality can range from fresh to highly saline, with the deeper groundwater generally less saline.
Other rock types found in the Sydney Basin include the Narrabeen shale, Mittagong formation, Illawarra Coal Measures, Newcastle Coal Measures, and Shoalhaven Group.
An aquifer is an underground layer of water-bearing permeable rock, rock fractures or unconsolidated materials.
The Sydney Basin is an interim Australian bioregion and is both a structural entity and a depositional area, now preserved on the east coast of New South Wales, Australia and with some of its eastern side now subsided beneath the Tasman Sea. The basin is named for the city of Sydney, on which it is centred.
The geography of Sydney is characterised by its coastal location on a basin bordered by the Pacific Ocean to the east, the Blue Mountains to the west, the Hawkesbury River to the north and the Woronora Plateau to the south. Sydney lies on a submergent coastline on the east coast of New South Wales, where the ocean level has risen to flood deep river valleys (rias) carved in the Sydney sandstone. Port Jackson, better known as Sydney Harbour, is one such ria.
The Cumberland Plain, an IBRA biogeographic region, is a relatively flat region lying to the west of Sydney CBD in New South Wales, Australia. Cumberland Basin is the preferred physiographic and geological term for the low-lying plain of the Permian-Triassic Sydney Basin found between Sydney and the Blue Mountains, and it is a structural sub-basin of the Sydney Basin.
The Nubian Sandstone is a variety of sedimentary rock deposited on the Precambrian basement in the eastern Sahara, north-east Africa and Arabian Peninsula. It consists of continental sandstone with thin beds of marine limestones, and marls. The Nubian Sandstone was deposited between the Lower Paleozoic and Upper Cretaceous, with marine beds dating from the Carboniferous to Lower Cretaceous.
The Geology of Yorkshire in northern England shows a very close relationship between the major topographical areas and the geological period in which their rocks were formed. The rocks of the Pennine chain of hills in the west are of Carboniferous origin whilst those of the central vale are Permo-Triassic. The North York Moors in the north-east of the county are Jurassic in age while the Yorkshire Wolds to the south east are Cretaceous chalk uplands. The plain of Holderness and the Humberhead levels both owe their present form to the Quaternary ice ages. The strata become gradually younger from west to east.
The Triassic Lockatong Formation is a mapped bedrock unit in Pennsylvania, New Jersey, and New York. It is named after the Lockatong Creek in Hunterdon County, New Jersey.
Geologically the Australian state of New South Wales consists of seven main regions: Lachlan Fold Belt, the Hunter-Bowen Orogeny or New England Orogen (NEO), the Delamerian Orogeny, the Clarence Moreton Basin, the Great Artesian Basin, the Sydney Basin, and the Murray Basin.
Ashfield Shale is part of the Wiannamatta group of sedimentary rocks in the Sydney Basin. It lies directly on contemporaneously eroded Hawkesbury sandstone or the Mittagong formation. These rock types were formed in the Triassic Period. It is named after the Sydney suburb of Ashfield. Some of the early research was performed at the old Ashfield Brickworks Quarry. This rock type is often associated with the Inner West and North Shore of the city. However, it has also been recorded at Penrith, Revesby, Bilpin and Mount Irvine.
Bringelly Shale is a component of the Wianamatta group of sedimentary rocks in the Sydney Basin of eastern Australia. Formed in the Triassic Period, it has an extensive outcrop in the western parts of Sydney. The shale has its greatest geographical extent at Bringelly, near the suburb of Liverpool.
Minchinbury Sandstone is a component of the Wianammatta Group of sedimentary rocks in the Sydney Basin of eastern Australia.
The Mississippi Alluvial Plain is a Level III ecoregion designated by the Environmental Protection Agency (EPA) in seven U.S. states, though predominantly in Arkansas, Louisiana, and Mississippi. It parallels the Mississippi River from the Midwestern United States to the Gulf of Mexico.
The geology of Surrey is dominated by sedimentary strata from the Cretaceous, overlaid by clay and superficial deposits from the Cenozoic.
The geology of Ivory Coast is almost entirely extremely ancient metamorphic and igneous crystalline basement rock between 2.1 and more than 3.5 billion years old, comprising part of the stable continental crust of the West African Craton. Near the surface, these ancient rocks have weathered into sediments and soils 20 to 45 meters thick on average, which holds much of Ivory Coast's groundwater. More recent sedimentary rocks are found along the coast. The country has extensive mineral resources such as gold, diamonds, nickel and bauxite as well as offshore oil and gas.
The geology of Tanzania began to form in the Precambrian, in the Archean and Proterozoic eons, in some cases more than 2.5 billion years ago. Igneous and metamorphic crystalline basement rock forms the Archean Tanzania Craton, which is surrounded by the Proterozoic Ubendian belt, Mozambique Belt and Karagwe-Ankole Belt. The region experienced downwarping of the crust during the Paleozoic and Mesozoic, as the massive Karoo Supergroup deposited. Within the past 100 million years, Tanzania has experienced marine sedimentary rock deposition along the coast and rift formation inland, which has produced large rift lakes. Tanzania has extensive, but poorly explored and exploited natural resources, including coal, gold, diamonds, graphite and clays.
The geology of Nigeria formed beginning in the Archean and Proterozoic eons of the Precambrian. The country forms the Nigerian Province and more than half of its surface is igneous and metamorphic crystalline basement rock from the Precambrian. Between 2.9 billion and 500 million years ago, Nigeria was affected by three major orogeny mountain-building events and related igneous intrusions. Following the Pan-African orogeny, in the Cambrian at the time that multi-cellular life proliferated, Nigeria began to experience regional sedimentation and witnessed new igneous intrusions. By the Cretaceous period of the late Mesozoic, massive sedimentation was underway in different basins, due to a large marine transgression. By the Eocene, in the Cenozoic, the region returned to terrestrial conditions.
The geology of South Dakota began to form more than 2.5 billion years ago in the Archean eon of the Precambrian. Igneous crystalline basement rock continued to emplace through the Proterozoic, interspersed with sediments and volcanic materials. Large limestone and shale deposits formed during the Paleozoic, during prevalent shallow marine conditions, followed by red beds during terrestrial conditions in the Triassic. The Western Interior Seaway flooded the region, creating vast shale, chalk and coal beds in the Cretaceous as the Laramide orogeny began to form the Rocky Mountains. The Black Hills were uplifted in the early Cenozoic, followed by long-running periods of erosion, sediment deposition and volcanic ash fall, forming the Badlands and storing marine and mammal fossils. Much of the state's landscape was reworked during several phases of glaciation in the Pleistocene. South Dakota has extensive mineral resources in the Black Hills and some oil and gas extraction in the Williston Basin. The Homestake Mine, active until 2002, was a major gold mine that reached up to 8000 feet underground and is now used for dark matter and neutrino research.
The geology of Mississippi includes some deep igneous and metamorphic crystalline basement rocks from the Precambrian known only from boreholes in the north, as well as sedimentary sequences from the Paleozoic. The region long experienced shallow marine conditions during the tectonic evolutions of the Mesozoic and Cenozoic, as coastal plain sediments accumulated up to 45,000 feet thick, including limestone, dolomite, marl, anhydrite and sandstone layers, with some oil and gas occurrences and the remnants of Cretaceous volcanic activity in some locations.
Groundwater in Nigeria is widely used for domestic, agricultural, and industrial supplies. The Joint Monitoring Programme for Water Supply and Sanitation estimate that in 2018 60% of the total population were dependent on groundwater point sources for their main drinking water source: 73% in rural areas and 45% in urban areas. The cities of Calabar and Port Harcourt are totally dependent on groundwater for their water supply.
The Ciechocinek Formation, formerly known in Germany as the Green Series is a Jurassic geologic formation that extends across the Baltic coast, from Grimmen, Germany, to Nida, Lithuania, with its major sequence on Poland and a few boreholes on Kaliningrad. It's mostly know by its incredible entomofauna, composed of more than 150 species of different groups of insects, as well it's marine vertebrate fossils, including remains of sharks, actinopterygians and marine reptiles, along terrestrial remains of Dinosaurs, including the early thyreophoran Emausaurus and others not yet assigned to a concrete genus. It's exposures are mostly derived from active clay minning of a dislocated glacial raft with exposed Upper Pliensbachian to late Toarcian shallow-marine sediments. Starting with coarse and fine sand deposits with concretions, the pure clay of the Ciechocinek Formation, after the falciferum zone, was deposited in a restricted basin south of the Fennoscandian mainland. It hosts a layer full of carbonate concretions, where a great entomofauna is recovered. The Ciechocinek Formation is the sister unit of the Sorthat Formation of Bornholm, being it's frontal brackish system, and the Lava Formation of Lithuania, a foreshore setting of the deltaic/lagoonar depositions of the Sorthat, located at the south of this last one, and sharing material between both due to the presence of a measured deltaic system that developed between the two units. The Ciechocinek Formation was, in the lower-late Toarcian a depositional area located north-eastern margin of the North German Basin, where the Sorthat Formation and the northern part of the island of Rügen, both at the north, provided the terrestrial elements of the Ciechocinek Formation taphocoenosis. The Posidonia Shale, deposited mostly on nearby deeper parts of this basin interfinger with the Ciechocinek Fm in the western parts of the states of Mecklenburg-Western Pomerania and Brandenburg. Its main equivalents are the Posidonia Shale, upper part of the Rydeback Member, Rya Formation, the Fjerritslev Formation, the Sorthat Formation (Bornholm) or the Lava Formation (Lithuania). There are also coeval abandoned informal units in Poland: Gryfice Beds, Lower Łysiec beds, or the "Estheria series".