ELECTEIC PEAK SECTION". 



51 





Num 

 ber. 





21 



1 ' 

 I 



20 

 19 



,18 





17 





16 



o 



A 



n 



1 10 

 9 



q 



r 6 



I 5 



•-5 



§J 



Q 



% i 



-a 1 « 



IS I 



Section of beds exposed on southeast spur of Electric Peal- — Continued. 



Feet. 



Calcareous sandstones, changing to pure sandstones at the bottom 175 



Sandstone, mottled and carbonaceous 60 



Sandstone, indurated and argillaceous 20 



Sandstones, speckled . 10 



Andesite-porphyry, much decomposed 15 



Calcareous sandstone 30 



Sandstone, indurated, argillaceous 50 



Andesite-porphyry 30 



Interval, no exposure 100 



Limestone, very impure, argillaceous and arenaceous 10 



Interval, no exposure 100 



Indurated sandstone 10 



Shales, very dark slate-colored, argillaceous rocks which are poorly exposed 300 



Sandstone, indurated to granular quartzite 5 



Interval, no exposure 75 



Indurated sandstone 10 



90 



Sandstones and arenaceous limestones, with two intruded sheets of andesite-por- 

 phyry aggregating 15 feet in thickness 160 



Interval, no exposure, but showing debris of dark-colored carbonaceous shales 



belonging to bed below 300 



Andesite-porphyry, much decomposed 15 



Carbonaceous, argillaceous shale 100 



Sandstone 20 



Interval, no exposure 50 



Limestone 5 



Interval, no exposure 50 



Conglomerate and sandstone, broken through by andesite-porphyry 5 



Arenaceous limestone 5 



Arenaceous limestones, passing downward into sandstones, cross bedded, and chang- 

 ing to limestones near base 45 



Interval, no exposure 50 



Sandstone, dark gray, mottled with carbonaceous matter, fine grained and not indu- 

 rated 5 



Interval, no exposure 100 



Limestone 100 



Interval, no exposure 15 



Quartzite and highly indurated calcareous sandstones 200 



Limestone, light cream colored; bands of red limestone exposed along north bank 



of Gardiner River, 200 feet below top 250 



Limestone, brownish gray, dense 50 



Total thickness of section 3, 478 



Thickness of intrusive sheets 148 



Total thickness of sedimentary rocks 3, 330 



