GEOLOGY OF THE LAKE PLACID QUADRANGLE I5 



In the Grenville area about lyi miles a little east of north of 

 Keene, well-bedded quartzites and hornblende gneisses are prom- 

 inently developed. 



The area between 2 and 3 miles north of Keene shows a number 

 of large exposures of typical hornblende-feldspar gneiss with one 

 small limestone outcrop in the southeast. 



On Styles brook, just above the falls, well-stratified Grenville 

 hornblende gneiss and hornblende-garnet gneiss with some inter- 

 bedded green pyroxene gneiss form the walls of a small gorge. 



The Red Rock area shows very fine big exposures of variable 

 well-stratified quartzite, some sharply defined beds being rich in 

 green pyroxene, others in red garnets, and still others in phlogo- 

 pite. Most of the rock contains flakes of graphite. 



The small area lyi miles northwest of Keene shows light-gray 

 feldspar-mica-graphite gneiss. According to Kemp's 1898 map, 

 limestone occurs here, but this was not seen by the writer. 



The small Grenville areas east of Keene show green pyroxene 

 gneiss and quartzite. 



Area near Upper Jay, In this area, southwest of the village, 

 the main body of Grenville appears to be dark hornblende-feldspar 

 gneiss with quartzite or green pyroxene gneiss sometimes locally 

 developed. Crystalline limestone and gneiss outcrop in the eastern 

 corner of this area. 



Wilmington mountain areas. In the area at the southern end 

 of Wilmington mountain there are many fine big outcrops of well- 

 stratified Grenville. The rocks are mostly green pyroxene-feldspar 

 gneisses, biotite-feldspar gneisses, and some hornblende gneisses 

 interbedded. In and about the graphite mines in the central-eastern 

 part of the area there is considerable crystalline limestone associated 

 with some pyroxene-garnet rocks. 



The large West Kilns-Middle Kilns area shows a considerable 

 number of good outcrops. On the side of Wilmington mountain 

 the principal rocks are hornblende-feldspar gneisses and green 

 pyroxene gneisses, both of these at times carrying garnets. Ouartz- 

 feldspar-mica gneiss and almost pure quartzite are there more 

 locally developed. Within one-half of, a mile east of West Kilns 

 there are several ledges of clearly bedded quartz- feldspar-phlogo- 

 pite-graphite gneisses, considerably weathered and rusty looking. 

 Near the road three-fourths of a mile east of West Kilns, Gren- 

 ville limestone and quartzite are poorly exposed, and one-fourth of 

 a mile east of this, by the road, pyroxene-feldspar-quartz gneiss 



