GEOLOGY OF OGDENSBURG 43 



12. 2' 5" Massive blue, granular dolomite, weathering brown. 



II. 11'' Thinner layer of gray, flinty dolomite. 



10. 2' 3" Massive gray, granular dolomite, to base of quarry. 



Views of this upper quarry are shown in plates 5 and 6. Directly 

 beneath it, and extending down nearly to the river level is another 

 quarry, carrying the section down. 



9. 13' Estimate of gap between last, and exposures beneath. 



c, , ^„ Heavy bed of gray, finely granular dolomite ; weathers 

 brown, with lined edges. 



7. i' 2" Thin-bedded dolomite and shale, poorly exposed. 



6 i' q" Massive bed of hard, iron-gray, finely granular dolo- 

 ^ mite, weathering thin bedded. 



Very solid, massive beds of dark-blue, granular dolo- 

 5. 7' 6'' mite, beds splitting when weathered; near base a lamin- 

 ated bed, and a shale parting at base. 



, „ A single massive layer like that above, also with a 

 ^' I inch shale parting at base. 



,, Thin layer of flinty, gray dolomite, fucoidal markings 

 on surface, and an irregular base with a shale parting. 



, „ Layer of blue, finely granular dolomite, with Ophi- 

 letas ; a thin shale parting beneath. 



I. 2' 6" Massive, blue, granular dolomite, to bottom of quarry. 



68' 6" total thickness. 



We are unable definitely to tie up this section with that 4 miles 

 to the southwest, and given on page 40. We miss here the 20 foot 

 thickness of the flinty, thin-bedded dolomites at the top of that 

 quarry. Beds 3 to 9 of this section may represent this thin-bedded 



