MARYLAND GEOLOGICAL SURVEY 95 



Stratigraphic Eelations. — The Wicomico formation is built as a 

 terrace lying irregularly and unconformably on older rocks which extend 

 from pre-Cambrian and Paleozoic down to the latest members of the 

 Miocene period. It is believed to lap up about the borders of the Sun- 

 derland formation and to lie unconformably on its basal portions. It 

 lies at a distinctly lower level from that of the Sunderland and is sepa- 

 rated from it by a scarp which forms a prominent feature of the topog- 

 raphy (Plate VIII). The surface of the Wicomico formation forms the 

 surface of the country on which it is developed with the exception of its- 

 margins, which are doubtless overlaid unconformably in their lower por- 

 tions by the next younger formation, the Talbot. 



The Talbot Formation. 



The name Talbot, suggested by Talbot county, where the formation is 

 well developed, was first proposed by the author in May, 1901. It is 

 equivalent to the younger portions of Darton's Later Columbia as de- 

 scribed and mapped by him in the Washington folio, U. S. Geological 

 Survey, 1901. In New Jersey there is no one formation described which 

 is equivalent to it, but it contains parts of the Cape May and Pensauken 

 formations of Salisbury. 



Areal Distribution. — The Talbot formation extends from South 

 Amboy across southern New Jersey, Pennsylvania, Delaware, and Mary- 

 land into Virginia, from which point it is evidently continued south- 

 ward to an unknown distance. In Maryland it occupies the area between 

 the margin of the older surficial deposits and the seashore (Plate I). 

 It wraps about the Wicomico and other terrace deposits as a border and 

 extends up reentrant valleys as a veneer. Erosion has attacked this 

 terrace to such a slight extent that it may be considered as continuous, 

 although here and there small areas have been separated from the other- 

 wise unbroken surface. It finds its greatest development on the Eastern 

 Shore and particularly in the southern portions of this area, where it 

 forms broad flats which decline lower and lower until they pass into 

 marches and blend imperceptibly with the beach. On the Western 

 Shore it also has an extensive development, particularly toward the head 



