Dating of rocks fossils and geologic events lab Webcam chat instant random
A lot of things that happen during geologic processes, such as the cooling and crystallizing of a magma, the erosion of landmasses, the transport of sediment by rivers, the filling up of ocean basins, all these processes can be observed in action in nature or in laboratory analogues (melting and crystallizing of rock in the lab, crystallization of salt from solution, weathering of building stones, floods of rivers, erosion of river banks, the filling in of embayments on the Mississippi delta within some decades).
We learn from these observations what kind of current velocities are needed to produce cross-bedding in a given grain size, and we realize that cross-bedding can be used as an indicator of current flow direction.
For example, sediment supply to the oceans is not a constant flux of matter.
There is a considerable episodic component to sedimentation, e.g.
storms are major agents of sediment redistribution in shelf seas, floods and exceptionally strong rains are responsible for most of the erosion and sediment redistribution on the continents.
Undoubtedly, the physical and chemical principles (e.g.