LAMOUKEUX SECTION. 67 



The Lamoureux Section. The section along the limestone ridge northeast 

 of the head of Lamoureux Canyon (atlas sheet ix) exposes 4,300 feet of 

 strata, the lowest members resting immediately upon the Eureka quartzite of 

 the flat-top hill about three-quarters of a mile south of Atrypa Peak. It is 

 impossible to say just how great a thickness of these beds should be 

 assigned to the Lone Mountain epoch. Unquestionajbly the lower members 

 of the Silurian are wanting, and if a line be drawn placing the alternating 

 blue and light gray bedded rocks No. 6, in the Devonian, it would give 

 about 800 feet to the lower group. About 500 feet above this line a fossil- 

 iferous belt comes in, carrying a well known Devonian fauna. This fossil- 

 iferous belt may be traced around to the east slope of Atrypa Peak, where 

 a most abundant fauna occurs rich in generic and specific forms. Here at 

 Atrypa Peak, however, there are nearly 2,000 feet of strata below the fos- 

 siliferous belt as against 1,300 feet in the Lamoureux Section before reaching 

 the Eureka quartzite, but as the inclination of the beds can not well be deter- 

 mined no accurate measurement of the thickness can be given. Apparently 

 the lowest horizon at Atrypa Peak is below the one shown in the section, 

 although the character of the sedimentation is much the same. 



The section is as follows : 



Section Hast of Lamoureux Canyon 4,300 feet. 



Feet. 



1. Brown and blue limestone, well bedded, with occasional 



mottled beds 300 



2. Brownish gray, finely striped, well bedded limestone, with 



corals 1, 000 



3. Dark blue, light gray, and brownish limestone 1, 000 



4. Alternating dark and light limestone 500 



5. Fossiliferous shaly belt 200 



6. Light blue and gray bedded limestone 500 



7. Light colored siliceous limestone, with indistinct bedding. . 800 



g ( Thin layer of black siliceous limestone. 

 ' ( Eureka quartzite. 



4,300 



County Peak Section. On the east side of the Eureka District, in the region 

 of County Peak, the Devonian rocks offer still another section quite similar 

 in the character of its sedimentation to those already given. It includes a 

 portion of the Lone Mountain rocks exposed in the bluffs on the east side 



