|
muds and mudstones
Book article from: The Oxford Companion to the Earth
muds and mudstones Mud and its indurated...hardened) equivalent mudstone are the most common...and ‘mudstone’ are...those of sands than mudstones. Very fine-grained...Bedded siltstone Mudstone Claystone Laminae...called carbonate mudstones . Mixtures of siliciclastic...
|
|
|
badlands
Book article from: The Oxford Companion to the Earth
...badlands. Relatively impermeable sedimentary rocks, such as mudstones and clay-cemented sandstones, are particularly susceptible...form of tunnels can also occur. Sedimentary rocks such as mudstones often contain a variety of clay minerals, including swelling...
|
|
|
deep-water sediments
Book article from: The Oxford Companion to the Earth
...active margins. Thick sequences of interbedded sandstones and mudstones/shales which contain sands with graded bedding and displaced...faunas, with planktonic and nektonic faunas in the interbedded mudstones, are common features in the geological column. In addition...
|
|
|
limestones
Book article from: The Oxford Companion to the Earth
...mineral calcite, but also as aragonite, which has the same chemical composition but a different crystal structure. After mudstones and sandstones, limestones are the next most abundant type of sedimentary rock. They extend over huge areas of the continents...
|
|
|
tropical landforms
Book article from: The Oxford Companion to the Earth
...short distances. Much of the island of Borneo is made up of cuestas of Tertiary sandstones with intervening areas of weak mudstones within shallow weathering profiles, but in the west of the island the igneous rocks of the Thai–Malay Peninsula...
|
|
|
sand and sandstone
Book article from: The Oxford Companion to the Earth
...by chemically precipitated cement or a recrystallized matrix of finer sediment. Sand and sandstone are second to muds and mudstones in abundance, and form approximately 10–15 per cent of the total sediments of the Earth's crust. The size...
|
|
|
chalk
Book article from: The Oxford Companion to the Earth
...fact gypsum, calcium sulphate.) Chalk in the first of these senses is a very pure, white, fine-grained silty carbonate mudstone. It is a rock-type that is particularly well developed in the upper Cretaceous of north- western Europe and the western...
|
|
|
cleavage and other tectonic foliations in rocks
Book article from: The Oxford Companion to the Earth
...transition from cleavage to gneiss represents a progression in metamorphic intensity during deformation. If an unmetamorphosed mudstone is progressively metamorphosed and deformed, the grain size and mineral segregation in the evolving foliated rock increase...
|
|
|
gravel and conglomerate
Book article from: The Oxford Companion to the Earth
...not deposited by traction currents but by sedimentary gravity flows and other processes. The terms diamictite or pebbly-mudstone have also been used for this type of deposit. Glacial tills (boulder clays) and their ancient equivalents tillites are of...
|
|
Metamorphic Grade
Encyclopedia entry from: The Gale Encyclopedia of Science
...metamorphism. In the order of increasing pressure and temperature, the metamorphic rocks formed from the sedimentary rocks shale or mudstones are slate, phyllite, schist and gneiss; from volcanic tuff (ash turned to rock), various types of schist and amphibolite...
|
