National Geographic : 1894 May 23
66 Hayes and Campbell-Appalachian Geomorphology. appearance of the first two papers above cited. He has carried his observations somewhat further toward the interior and de scribes two well marked baselevel peneplains in eastern Penn sylvania, New Jersey and portions of New England, the formation of which, he ascribes to long continued erosion in Cretaceous and Tertiary time. A general seaward tilting of the peneplain is described, but no attempt is made to locate the axes of their deformations. In 1890 Davis published a more comprehensive paper,t bringing in review all previous publications on the base levels of the Atlantic slope and discussing the probable continua tion of the peneplains, found in the northern portion southwest ward over the whole of the Appalachian province. Thus the broad outlines and to some extent the details of post Paleozoic history of the Atlantic slope and Mississippi embay ment have been determined, but for most of the interior the details are still wanting. The present paper is an attempt to supply in some measure this deficiency. THE PROVINCE DEFINED. For present purposes the southern Appalachian province is regarded as embracing the region south of the Ohio and Potomac rivers and limited toward the east, south, and west by the Cre taceous and the later formations of the coastal plain and Missis sippi embayment. One or both of the present writers are per sonally familiar with the greater part of this region, and many observations made in connection with the work of the Appa lachian division of the United States Geological Survey are here for the first time brought together. The location of the region is exceptionally favorable for the study of its geomorphology. Surrounded on three sides by Mesozoic and later deposits, the relations of land and water which prevailed during post-Paleozoic time are fairly well determined. The character of the sediments serves to establish correlations between them and their corre sponding erosion features. The intersection of erosion planes with deposits of known age serves to fix the date of each erosion period within narrow limits. Finally, the absence of glaciation and glacial deposits renders the interpretation of topographic forms and of drainage systems much easier than in regions tThe geologic Dates of Origin of certain topographic Forms on the Atlantic Slope of the United States, by W. M. Davis: Bull. Geol. Soc. Am., vol. ii,. 1890, pp. 545-581.
1894 Jun 22
1894 Apr 25