The climate in late geologic time was very different from that which prevails to-day.
This principle has been demonstrated recently among Tertiary rhinoceroses and titanotheres, in which remains of four or five genetic series in the same geologic deposits have been discovered.
in the order of decreasing geologic age and maturity.
This is not due to environmental conditions solely, because senescent branches of normal progressive groups are found in all geologic horizons, beginning, for gastropods, in the Lower Cambrian.
Abich (Sur la structure et la geologic du Daghestan, 1862), the successive folds of Jurassic limestones and slates, all nearly parallel to the Caucasus, which form lofty, narrow plateaus.
Such a drying up has been in progress during long geologic ages, but doubt exists as to its practical importance at the present time.
These were successive stages in the geologic process which has created, and is still actively modifying, the state.
The geologic record is, as perhaps is to be expected, exceedingly poor, except as regards the calcareous Siphonales, which are well represented at various horizons, from the Silurian to the Tertiary; even the Diatomaceae, which are found in great quantities in the Tertiary deposits, do not occur at all earlier than the chalk.
Igneous intrusions consist only of unimportant dikes of trap. The most striking and uniformly characteristic geologic feature of the mountains is their internal structure, consisting of innumerable parallel, long and narrow folds, always closely appressed in the eastern part of any crosssection (Piedmont Plateau to Great Valley), less so along a central zone (Great Valley and Valley Ridges), and increasingly open on the west (Allegheny and Cumberland Plateaus).
The mountain chains, which from their peculiar geologic character are known as of the "Basin Range type" (not exactly conterminous in distribution with the Basin), are echeloned in short ranges running from N.
For Geology see Tchihatcheff, Asie Mineure, Geologic (Paris, 1867-1869); Schaffer, Cilicia, Peterm.
Salisbur Geologic Processes (New York) and Earth History (2 vols., New York J.
Its upheaval above the great sea which submerged all the north-west of the Indian peninsula long after the Himalaya had massed itself as a formidable mountain chain, belongs to a comparatively recent geologic period, and the same thrust upwards of vast masses of cretaceous limestone has disturbed the overlying recent beds of shale and clays with very similar results to those which have left so marked an impress on the Baluch frontier.
For its significance as a former (geologic) connexion between the Sea of Azov and the Caspian Sea, see Caspian Sea.
19 a nuances, or grades of difference, which are the more gradual the more finely we dissect the geologic column, while the terms species, sub-species and variety are generally based upon a sum of changes in several characters.
There is ample proof throughout the country of alterations of level within recent geologic periods; and there have even been compressions, resulting in a relative rise of the ground, over the crests of anticlinal folds, within historic record.
The theory of past migrations from continent to continent, suggested by Cuvier to explain the replacement of the animal life which had become extinct through sudden geologic changes, was prophetic of one of the chief features of modern method - namely, the tracing of migrations.
Were the geologic record complete he would be able to trace the ancestry of man and of all other animals back to their very beginnings in the' primordial protoplasm.
See the separate articles on the states, and also the following references: - Topographic maps and Geologic Folios of the United States Geological Survey; Bailey Willis, "The Northern Appalachians," and C. W.
These horses are of the same geologic age (Upper Miocene) and 'were found in the same geographic region (South Dakota, U.S.A.).
Geologically the anthracite and bituminous coals mainly belong to the same formation, the Carboniferous, and this is especially true of the better qualities; though it is stated by the United States Geological Survey that the geQlogic age of the coal beds ranges from Carboniferous in the Appalachian and Mississippi Valley provinces to Miocene (Tertiary) on the Pacific coast, and that the quality of the coal varies only to a very uncertain degree with the geologic age.
geologic mapping in an accessible setting.
geologic formations, the sensors have not been gathering reliable data.
geologic map accompany each plate.
geologic history of the Earth's surface.
surficial rocks and soils, thus aiding geologic mapping of the basin fill.
This page includes a conventional geologic map of the region and a map that characterizes the assemblage of stratigraphic units as distinct terranes.
Taking the carbon exhumed by industrial combustion from the geologic past and stacking it into overripe living woodpiles is an approach of questionable wisdom.
Brown; folios 26, 28, 32, 34, 44, 69, 7 2, 77 and 160 of the Geologic Atlas of the United States; M.
The remark may conveniently find its place here that plants which have reached a high degree of adaptive specialization have come to the end of their tether: a too complicated adjustment has deprived them of the elasticity which would enable them to adapt themselves to any further change in their surroundings, and they would pass away with conditions with which they are too inextricably bound up. Vast floras have doubtless thus found their grave in geologic change.
Waagen's law of mutation, or the appearance of new parts or organs so gradually that they can be perceived only by following them through successive geologic time stages, appears to be directly contradictory to the saltation principle; it is certainly one of the most firmly established principles of palaeontology, and it constitutes the contribution par excellence of this branch of zoology to the law of evolution, since it is obvious that it could not possibly have been deduced from comparison of living animals but only through the long perspective gained by comparison of animals succeeding each other in time.
In general we find an analogy between the development of groups and of organs; we discover that each phyletic branch of certain organisms traverses a geologic career comparable to the life of an individual, that we may often distinguish, especially among invertebrates, a phase of youth, a phase of maturity, a phase of senility or degeneration foreshadowing the extinction of a type.
Radiometric data were also collected to map surficial rocks and soils, thus aiding geologic mapping of the basin fill.
Kehl Spring Campground is located in a picturesque stand of ponderosa pines right at the brink of one of Arizona's most amazing geologic features, the Mogollon Rim.
Geologic surveys were undertaken, construction plans began, and the Citadel was established in 1850 with the fortress manned with long range cannons and guns capable of taking out hostile ships entering the bay.
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