Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: May 25, 2025
The waters which deposit vein stones and ores are commonly hot, and in many cases they have derived their heat from intrusions of igneous rock still uncooled within the crust. The solvent power of the water is thus greatly increased, and it takes up into solution various substances from the igneous and sedimentary rocks which it traverses.
We must have a waterfall for power, a good place to hide our ship from observation, and I'd like to have a little seam of coal. We can use wood if we have to, but I think we can find some coal. This is all sedimentary rock it looks a lot like the country along the North Fork of the Flathead, in Montana. There are a lot of coal outcrops, usually, in such topography as this is."
It is an established geological doctrine, that sedimentary strata are liable to be changed, more or less profoundly, by igneous action.
It may naturally be asked how it comes that although no extensive fossiliferous deposits of the recent period, nor of any period intermediate between it and the ancient tertiary epoch, have been preserved on either side of the continent, yet that at this ancient tertiary epoch, sedimentary matter containing fossil remains should have been deposited and preserved at different points in north and south lines, over a space of 1100 miles on the shores of the Pacific, and of at least 1350 miles on the shores of the Atlantic, and in an east and west line of 700 miles across the widest part of the continent?
For the sedimentary formations are most readily distinguished by the different species of fossil animals and plants which they inclose, and of which one assemblage after another has flourished and then disappeared from the earth in succession.
Sedimentary strata have been carried down, by movements of the earth's crust, far below the surface, covered by other deposits, and subjected to great heat, which, aided by the water contained in the rocks and various chemical reactions, has effected a re-arrangement of the mineral contents of the strata, so that by molecular movements, the metamorphic crystalline rocks, including interstratified granites and greenstones, have been formed.
These angular fragments were probably thrown out from volcanic vents, and fell upon sedimentary matter then in the course of deposition. The recent investigations of Mr.
They include sedimentary deposits, showing the action of water, and even probable traces of organic remains, but they are, especially in their deeper and older sections, predominantly volcanic. They evince what we may call a volcanic age in the early story of the planet. But before we pursue this part of the story further we must interpolate a remarkable event in the record the birth of the moon.
There are, however, some that are of undoubted sedimentary origin, but highly metamorphosed. The general direction of foliation is a few degrees south of east, subject, of course, to many local changes.
Hence each of the sedimentary strata has its characteristic fossils, the remains of the animals and plants that lived during that particular period of the earth's history. When we make a comparative study of these strata, we can survey the whole series of such periods.
Word Of The Day
Others Looking