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The following is a list of rock types recognized by geologists. There is no agreed number of specific types of rock. There is no agreed number of specific types of rock. Any unique combination of chemical composition, mineralogy, grain size, texture, or other distinguishing characteristics can describe a rock type.
In ecology, an oasis (/ oʊ ˈ eɪ s ɪ s /; pl.: oases / oʊ ˈ eɪ s iː z /) is a fertile area of a desert or semi-desert environment [1] that sustains plant life and provides habitat for animals. Surface water may be present, or water may only be accessible from wells or underground channels created by humans.
Weald Clay or the Weald Clay Formation is a Lower Cretaceous sedimentary rock unit underlying areas of South East England, between the North and South Downs, in an area called the Weald Basin. It is the uppermost unit of the Wealden Group of rocks within the Weald Basin, and the upper portion of the unit is equivalent in age to the exposed ...
The Table Rocks were not protected until the 1970s. The rocks are home to over 70 species of animals and 340 species of plants, which includes over 200 species of wildflowers. Vernal pools atop the plateaus fill during the rainy season in winter and spring because the andesite is impermeable.
Thermal stress weathering is most effective when the heated portion of the rock is buttressed by surrounding rock, so that it is free to expand in only one direction. [13] Thermal stress weathering comprises two main types, thermal shock and thermal fatigue. Thermal shock takes place when the stresses are so great that the rock cracks ...
A craton is an ancient part of the Earth's continental crust which has been more or less stable since Precambrian times. Cratons whose ancient rocks are widely exposed at the surface, often with relatively subdued relief, are known as shields.
Badlands arise from a combination of an impermeable but easily eroded ground surface, sparse vegetation, and infrequent but heavy rainfall. [6] The surface bedrock is typically mudrock, sometimes with evaporites, with only occasional beds of more resistant sandstone. [5] Infrequent heavy rains lead to heavy erosional dissection.
An unconfined aquifer has no impermeable barrier immediately above it, such that the water level can rise in response to recharge. A confined aquifer has an overlying impermeable barrier that prevents the water level in the aquifer from rising any higher. An aquifer in the same geologic unit may be confined in one area and unconfined in another.