United States or Mali ? Vote for the TOP Country of the Week !
Professor Ramsay has remarked that there is a stratigraphical break; for in Kent, Surrey, and Sussex, at those few points where there are exposures of junctions of the Gault and Neocomian, the surface of the latter has been much eroded or denuded, while to the westward of the great chalk escarpment the unconformability of the two groups is equally striking.
What is termed stratigraphical geology is neither more nor less than the anatomy of the earth; and the history of the succession of the formations is the history of a succession of such anatomies, or corresponds with development, as distinct from generation.
The characters of the Upper and Lower Silurian rocks were established so fully, both on stratigraphical and palaeontological data, by Sir Roderick Murchison after five years' labour, in 1839, when his "Silurian System" was published, that these formations could from that period be recognised and identified in all other parts of Europe and in North America, even in countries where most of the fossils differed specifically from those of the classical region in Britain, where they were first studied.
Thomson and Dr. And I agree with Dr. If the word "chalk" is to be used as a stratigraphical term and restricted to Globigerina mud deposited during the Cretaceous epoch, of course it is improper to call the precisely similar mud of more recent date, chalk.
But hardly more than two centuries have elapsed since this fundamental problem was first exhaustively treated; it was only in the last century that the archaeological value of fossils their importance, I mean, as records of the history of the earth was fully recognised; the first adequate investigation of the fossil remains of any large group of vertebrated animals is to be found in Cuvier's "Recherches sur les Ossemens Fossiles," completed in 1822; and, so modern is stratigraphical palaeontology, that its founder, William Smith, lived to receive the just recognition of his services by the award of the first Wollaston Medal in 1831.
Luckily, in the old days fashions tended to be rigid; so that for the pre-historian two flints with slightly different chipping may stand for separate ages of culture as clearly as do a Greek vase and a German beer-mug for the student of more recent times. Enough concerning the stratigraphical method. A word, in the next place, about the pre-historian's main sources of information.
Samuel Richardson, at Bath, Smith astonished his friend by suddenly disarranging his classification, and re- arranging the fossils in their stratigraphical order, saying "These came from the blue lias, these from the over-lying sand and freestone, these from the fuller's earth, and these from the Bath building stone." A new light flashed upon Mr.
Such is the method of pre-history. It is called the stratigraphical method, because it is based on the description of strata, or layers. Let me give a simple example of how strata tell their own tale. It is no very remarkable instance, but happens to be one that I have examined for myself. They were digging out a place for a gas-holder in a meadow in the town of St.
Having regard to this general scheme of geological knowledge and thought, it is obvious that geological speculation may be, so to speak, anatomical and developmental speculation, so far as it relates to points of stratigraphical arrangement which are out of reach of direct observation; or, it may be physiological speculation, so far as it relates to undetermined problems relative to the activities of the earth; or, it may be distributional speculation, if it deals with modifications of the earth's place in space; or, finally, it will be ætiological speculation, if it attempts to deduce the history of the world, as a whole, from the known properties of the matter of the earth, in the conditions in which the earth has been placed.
What is termed stratigraphical geology is neither more nor less than the anatomy of the earth; and the history of the succession of the formations is the history of a succession of such anatomies, or corresponds with development, as distinct from generation.
Word Of The Day