Search results
Results from the WOW.Com Content Network
Oil shale formation takes place in a number of depositional settings and has considerable compositional variation. Oil shales can be classified by their composition (carbonate minerals such as calcite or detrital minerals such as quartz and clays) or by their depositional environment (large lakes, shallow marine, and lagoon/small lake settings).
The largest deposits are found in the remains of large lakes such as the deposits of the Green River Formation of Wyoming and Utah, USA. Large lake oil shale basins are typically found in areas of block faulting or crustal warping due to mountain building. Deposits such as the Green River may be as much as 2,000 feet (610 m) and yield up to 40 ...
As a result, shales are typically deposited in very slow moving water and are often found in lakes and lagoonal deposits, in river deltas, on floodplains and offshore below the wave base. [13] Thick deposits of shale are found near ancient continental margins [13] and foreland basins. [14]
Lacustrine deposits have gained more attention recently due to containing valuable source rocks of oil, coal, and uranium. Lacustrine deposits generally provide productive mining conditions but can prove challenging when underground mines are attempted due to the poor shear strength of clays and silts as well as the amount of moisture often locked in the layers due to a low permeability ...
The Messel lake bed was probably a center point for drainage from nearby rivers and creeks. A fossil of the primitive mammal Kopidodon, showing outline of fur. The pit deposits were formed during the Eocene Epoch of the Paleogene Period about 47 million years ago, based on dating of basalt fragments underlying fossilbearing strata. [7]
Oil shale is an organic-rich fine-grained sedimentary rock containing kerogen (a solid mixture of organic chemical compounds) from which liquid hydrocarbons can be produced. In addition to kerogen, general composition of oil shales constitutes inorganic substance and bitumens.
Glacial retreat began around 13,000 years ago and ended by around 11,000 years ago. However, ice-dammed lakes and isostatic rebound in the region played an important role in geomorphology for several more millennia. The Baltic Ice Lake gave way to the Yoldia Sea, Ancylus Lake and Littorina Sea, followed by the Limnea Sea.
A marl lake is a lake whose bottom sediments include large deposits of marl. [18] They are most often found in areas of recent glaciation [37] and are characterized by alkaline water, rich in dissolved calcium carbonate, from which carbonate minerals are deposited. [38]