118 .1. s. DILLER INDSTONE DIKES. 



Dikes of Poverty Gulch. — Poverty gulch is the next one in which the dikes 

 are exposed south of Roaring river. A group of them crosses the gulch at 

 12. oue ami one-fourth miles above its mouth mar Mr. Glass's. The largest 

 is 20 inches in width, five average from •"> to •"> inches, and Beveral are about 

 2 inches across. They are vertical, strike N. 13° E., directly in line with the 

 I rreat dike just noted on 1 {oaring river, and apparently a continuation of it. 



Dikes of Aiken Ghilch (Camp Creel). — The first dike seen Dear the mouth 

 of Aiken gulch is the Great dike traced from I {oaring river. Here it i- 5 

 feet in width, vertical, with strike N. 40° E. The northwestern wall is some- 

 what irregular. Bending small tongues out into the shale, and numerous 

 fragments of the shale are included in the dike. Generally, however, the 

 walls of the dike are sharp, well defined, and smooth, and are well exposed 

 from top to bottom of the bank, forty feet high. The edges here, as in many 

 ofthe other dikes, are apparently somewhat liner (e. </.. specimen 2393 > than 

 the middle portion (specimen 2-7.M . 



At 14 is a dike 8 inches in thickness, and at 1">, on the north bank ofthe 

 gulch, quarter of a mile above its mouth, there are six small dikes, ranging 

 generally from 2 to 12 inches thick. One of the number increases rather 

 suddenly to a width of 3 feet, but may not continue so large. They strike 

 N. 40° E. Near them a number of joints are exposed, and they are exactly 

 parallel to the dikes. A shorl distance further up the stream bed, on the 

 south bank, one ofthe dikes forms a good, wall-like exposure. 



Dikes of Middle Fork. — Ascending Middle fork, the first dike encountered 

 is a short distance above the mouth of Aiken gulch, where the (Jreat dike 

 appears in the northwest bank at 16. At 17 two 6-inch dikes cross the 

 creek. At 18, near Miller's, the Great dike again crops out, crosses the 

 stream, and forms a heavy wall upon the left, bank. It ranges from 3 to ."» 

 feet in thickness, strikes X. 12 E., and is cross-jointed, weathering out in 

 large, round bowlders. Nearby, upon the northwest side of the ( Jreat dike. 

 are two small dikes, 2 and 4 inches in thickness ; and upon the opposite side 

 i- another, 1 foot through. Joints appear in the shahs parallel to these dikes 

 where they cross the creek. A few hundred yards south of Miller's, on the 



trail leading over to .John Allen'-, on Dry creek, a 1 1-inch dike is exposed. 



On the left bank of the stream the Great dike continues southweetward 

 across a curve, reaching tic stream again three-quarters of a mile above 

 Miller's, w here i he greatest width of the dike, 8 feci, wa- observed. At this 

 point the jointing in the dike is less regular than usual, and very small frag- 

 ments of -hale are included in it. These fragments are small and flat and 

 are arranged with the scales of biotite parallel with the sides of the dike. 



I pon the weathered BUrface |||,. -hale j' r a- nt- fall away and produce 



-mall pit-. Near the middle the vein is somewhat banded. Here and there 

 are -mall veins of calcite. Although it i- well exposed upon the right bank 



