20 NEW YORK STATE MUSEUM 



shales, such characteristic graptoHtes as Didymograptus 

 n i t i d u s and Goniograptus thureaui having been 

 found in railroad cuts below Stuyvesant. 



In southeastern New York the complex problems involved in 

 the Tarrytozvn quadrangle have received attention from Dr 

 Charles P. Berkey who has been aided in his interpretations by 

 his extensive knowledge of the underground rock structure in 

 the course of the Catskill aqueduct. 



The Clove quadrangle involving an area of Precambric and 

 highly altered Paleozoic rocks east of Poughkeepsie has been 

 studied by Prof. C. E. Gordon and for the most part mapped. 

 The gneisses of the Highlands extend northward as a huge spur 

 in the southeastern part of the quadrangle, and on the west and 

 northwest are overlain by and faulted with the lower Camljric 

 quartzite which in turn is faulted with the Fishkill limestone. 

 Both quartzite and limestone continue northeastward from the 

 Poughkeepsie quadrangle and all three associated formations 

 present essentially the same relations in both areas. 



At Poughquag, in the town of Beekman, is the type locality 

 of the basal quartzite of southeastern New^ York and while fos- 

 sils have not yet been found in it, the structural relations clearly 

 demonstrate its identity w'ith the rock yielding Olenellus at 

 Johnsville in the town of East Fishkill. The basal quartzite 

 ends against the schist of West Pawling mountain about two 

 miles northeast of Poughquag. Between Poughquag and this 

 point, what appears to be the northern margin of the quartzite 

 forms " Garden Hollow." The drift is A^ery heavy along the 

 northern margin of the Highland spur, forming an exceptionally 

 fine drumlin topography near Storm ville, Green Haven and 

 Poughquag. Northeast of the last village, it greatly obscures the 

 relationships of quartzite, limestone and schist. 



The northern boundary of the Fishkill limestone followed east 

 from the Poughkeepsie area for a short distance presents the 

 same serrated character, a short toothlike spur appearing just 

 north of Sylvan lake. It then continues as a long narrow tongue- 

 like spur eight or ten miles north of Poughquag in the valley of 

 Fishkill creek and forms what is known as the " Clove." In 

 tracing the eastern boundary of the limestone with the schist, 

 a fine example of coarse fault brecciation was noted a mile and 

 a half north of the hamlet of Clo^e mdicating the character of 

 the contact. 



