File:Geology (1907) (14776043512).jpg

Identifier: geology00cham (find matches)
Title: Geology
Year: 1907 (1900s)
Authors: Chamberlin, Thomas C. (Thomas Chrowder), 1843-1928 Salisbury, Rollin D., 1859- joint author
Subjects: Geology
Publisher: New York, H. Holt and co.
Contributing Library: Internet Archive
Digitizing Sponsor: Internet Archive

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
on oierosion and in the development of mesas. Kp (Pierre formation) and Ktd (Trini-dad formation), Montana series; Kl, Laramie series; Nb Neocene basalt. The sec-tion is along the line AB of the map. (Hills, Elmoro, Colo., folio, U. S. Geol. Surv.) fusion, and baking, resulting in lava-like slag and brick-red banks ofindurated clay. The former has had, and is still having a notableeffect on the details of the topography developed by wind and water,while the latter gives striking color to the landscape. Incipient meta-morphism accompanied the heat developed by the combustion. Transition beds between Mesozoic and Cenozoic.—In general, theLaramie is conformable with the Montana below, as the precedingstatements imply, and unconformable with the Eocene (Tertiary) THE CRETACEOUS PERIOD. 155 above. The break between the Laramie and Eocene is locally a greatone,—has even been regarded as one of the greatest breaks recordedin the strata of the continent.1 Locally, however, the association
Text Appearing After Image:
Fig. 398.—Map of a small area in Colorado, showing the outcrops of faulted Cre-taceous formations. Kd, Dakota; Kys (Graneros shale), Kgn (Greenhorn lime-stone), Kcr (Carlisle shale), Kt (Timpas shale), and Ka (Apishapa shale), Coloradoseries; Kp (Pierre shale), Montana series; Tri, igneous rocks of Tertiary age.(Hills, Walsenburg, Colo., folio, U. S. Geol. Surv.) of the Laramie and Eocene is so intimate that agreement concern-ing the reference of certain beds, and even thick formations, has notbeen reached. Within what has often been called the Laramie series,there are local unconformities. Where these are slight, they prob-ably have little significance in determining the classification of thebeds. Slight unconformities are common in the Pennsylvanian systemof the east, with which this series is most nearly allied in genesis. But 1 Emmons, Orographic movements of the Rocky Mountains. Bull. G. S. A.,Vol. I, p. 285. 150 GEOLOGY. there seems to be one unoonformity which is neither slig

Note About Images