UPPER RED BEDS OF THE BLACK HILLS 37 1 



Feet. Inches, 

 VII. ONE MILE NORTHWEST OF MINNEKAHTA. 



_ . ( Fissile s[reen-drab shale ------ 5o±: 



Jurassic \ ^ . .. . . , 



( Friable white sandstone ----- 25 



Contact covered. 



Chocolate-brown clayey sandstone with patches of green clay 10+ 



Concealed. 



Light red sandy shale with some small green specks and streaks 10+ 



Chocolate-brown mudstone ------- 4 



Brown-red clayey sandstone with 5 ' bed of gypsum and some 



green streaks ........ 20 



Red sandy shales with some green streaks - - - - 30 



Light brick- red clayey sandstone with network of thin gypsum 



veins -.---.-.-- 60 



Impure red-stained gypsum ....... 12 



Red sandy shale - - - - - - -- - .. 6 



Pure white gypsum - - - - - - - - -.. 2 



Red sandy shale ----.--.-.. i 



Green shale ------.---.. ^ 



Red sandy shale with network of gypsum veins - - - 50 



Massive white gypsum -------- 5 



Red sandy shale with network of gypsum veins - - - 15 



Massive white gypsum .---..-. 20 



Red sandy shale with gypsum veins - - . . _ 5 



Massive white gypsum ---.-..- 3 



Red sandy shale --------- 6 



Massive white gypsum -------- i 



Red sandy shale with gypsum veins - - - - - 10 



Mottled gypsum (admixture of red clay) - - - - - 20 



Brick-red sandy shale - - - - - - - - iio 



Purple limestone (Permian) ------- 50 



VIII. FOUR MILES WEST OF MINNEKAHTA, 



Massive, friable sandstone, red superficially; white within. 

 (Jurassic). 



Undulating contact — sharp change. 

 Hard chocolate-brown sandy clay. 



IX. ONK-HALF MILE NORTHEAST OF X. 



f Massive fine-grained sandstone ; superficially stained 



red — paler to white within - . - - 30-40 

 Jurassic -{ Shale and thin-bedded drab-green sandstone - 15-20 



Buff sandstone. 

 '-Massive white sandstone superficially red. 



