IxXXVi GEOLOGICAL AXD PALEONTOLOGICAL RELATIONS 



hilis, Panopea goldfussi, Callocardia sayana, Yenus campechiensis var. 

 mortoni, Isocardia frcderna, Pliacoides anodonta, Pecten madisonius, P. 

 jeffersonius, etc. 



Local Sections. 



The formations and zones described above are based on a large nnm- 

 ber of local sections found scattered throngliout the Miocene area of 

 Maryland. The most continuous and complete series of sections is found 

 along Chesapeake Bay from Fairhaven southward to Drum Point, liut 

 other instructive and important sections are found in the valleys of the 

 Potomac and Patuxent rivers and along many of the rivers of the 

 Eastern Shore. 



CHESAPEAKE BAY SECTIONS. 



The most complete section of the Miocene deposits along the Atlantic 

 Coast occurs in the famous Calvert Cliffs from Chesapeake Beach south- 

 ward to Drum Point. Throughout this distance the bluffs yield a com- 

 plete sequence of the various beds of the formations, and the fossils are 

 numerous and usually very well preserved. The entire Chesapeake Bay 

 section is given in detailed columnar sections in Plate Y, and the rela- 

 tions of zone to zone indicated. The detailed description of each of these 

 sections will now be given. 



I. Section on a southern branch of Lyons Creek. 



Feet. 



r White diatomaceous clay (Zone 3) 5 



White sandstone containing following fossils: Ecphora 



■^ .2 I tricostata, Panopea whitfieldi, P. americana, Corbula 



■^ rt -i elevata, Phacoides contractus. Venericarclia granu- 



Miocene. ^ g j ^^^^^ Astarte cuneiformis, A. thomasi, Thracia con- 



O o radi. Pecten madisonius, P. humphreysii, Chione 



^ I latilirata, Cytherea staminea (Zone 2) 1 



I Brown sand containing Phaciodes contractus (Zone 1) 6 

 Eocene Greenish gray sandy clay 35 



Total 47 



II. Section at Fairhaven. one-half mile south of icharf. 



Feet. 



Pleistocene. Gravel, sand and clay 10 



{ Diatomaceous sandy clay bleached to a whitish color, 

 ^ I jointed so as to have a rough columnar appearance 



carrying Phacoides contractus (Zone 3, in part) .... 24 

 Diatomaceous greenish sandy clay breaking with con- 

 coidal fracture, carrying Phacoides contractus and 

 O o bearing rolled and reworked fossils from Eocene in 

 fe I lower 2 Vo feet (Zone 3, in part) 36 



Total 70 



Miocene, oj "Je 



^ a 



