Crossword clues for mudstone
mudstone
Wiktionary
n. (context petrology English) A fine-grained sedimentary rock whose original constituents were clays or muds.
Wikipedia
Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Grain size is up to 0.0625 mm (0.0025 in) with individual grains too small to be distinguished without a microscope. With increased pressure over time, the platey clay minerals may become aligned, with the appearance of fissility or parallel layering. This finely bedded material that splits readily into thin layers is called shale, as distinct from mudstone. The lack of fissility or layering in mudstone may be due to either original texture or the disruption of layering by burrowing organisms in the sediment prior to lithification. Mud rocks such as mudstone and shale comprise some 65% of all sedimentary rocks. Mudstone looks like hardened clay and, depending upon the circumstances under which it was formed, it may show cracks or fissures, like a sun-baked clay deposit.
Mudstone can be separated into these categories:
- Siltstone – more than half of the composition is silt-sized particles.
- Claystone – more than half of the composition is clay-sized particles.
- Mudstone – hardened mud; a mix of silt and clay sized particles. Mudstone can include:
- Shale – exhibits lamination or fissility.
- Argillite – has undergone low-grade metamorphism.
Usage examples of "mudstone".
First, since the particle size of the grains in a mudstone is very small, the depositional environment in which the mudstone was formed had to have been still water, otherwise the tiny particles would have kept right on going.
And then it would turn into mudstone, and then interbedded sand and mud.
Henry knew that the mudstones had been dumped from icebergs, floating on the surface of the polar ocean that had once covered this land, an ocean four hundred million years gone.
It sweeps away any fine-grained material, including, in time, the solid rock of sandstones and mudstones, but it can’t move the bigger material, like chunks of bone.
Here and there he saw sandbars strewn with black or brown boulders mudstones and shales, said McCann, laid down in ancient swamps.
The land itself had been remolded, laid down as layer upon layer of volcanic ash, interspersed with broad beds of shale and mudstone.