The Origin of Continents and Oceans

· Courier Corporation
5,0
4 recensioner
E-bok
246
Sidor
Betyg och recensioner verifieras inte  Läs mer

Om den här e-boken

Since its inception modern geology has been faced with an important group of problems: explaining parallel formations that are separated by great distances of sea; accounting for isolated life forms in widely separated areas (such as lemurs in Madagascar and India); explaining pre-pleistocene glaciations, and similar problems. The usual explanation has been to assume the one-time existence of land bridges (such as the hypothetical Lemuria) or parallelisms or diffusion with lost intermediary steps.
In 1915, however, one of the most influential and most controversial books in the history of science provided a new solution. This was Alfred Wegener's Entstehung der Kontinente, which dispensed with land bridges and parallel evolutions and offered a more economical concept. Wegener proposed that in the remote past the earth's continents were not separate (as now), but formed one supercontinent which later split apart, the fragments gradually drifting away from one another. Wegener created his supercontinent with attractive simplicity by tucking the point of South America into the Gulf of Guinea, coalescing North America, Greenland, and Europe, rotating Australia and Antarctica up through the Indian Ocean, and closing the remaining gaps. Wegener then explained various phenomena in historical geology, geomorphy, paleontology, paleoclimatology, and similar areas of science in terms of this continental drift. To back up his revolutionary theory he drew upon a seemingly inexhaustible find of data. Later editions of his book added new data to refute his opponents or to strengthen his own views in the violent scientific quarrel that arose.
Even today this important question remains undecided, and geologists are divided into strongly opposed groups about the Wegener hypothesis. At the moment it seems to be gaining steadily in acceptance. It is one of the two basic theories of earth history, and since it has often been misrepresented in summary, every earth scientist owes it to himself to examine its theories and data.

Betyg och recensioner

5,0
4 recensioner

Betygsätt e-boken

Berätta vad du tycker.

Läsinformation

Smartphones och surfplattor
Installera appen Google Play Böcker för Android och iPad/iPhone. Appen synkroniseras automatiskt med ditt konto så att du kan läsa online eller offline var du än befinner dig.
Laptops och stationära datorer
Du kan lyssna på ljudböcker som du har köpt på Google Play via webbläsaren på datorn.
Läsplattor och andra enheter
Om du vill läsa boken på enheter med e-bläck, till exempel Kobo-läsplattor, måste du ladda ned en fil och överföra den till enheten. Följ anvisningarna i hjälpcentret om du vill överföra filerna till en kompatibel läsplatta.