108 proceedings: geological society 



quartz is distinctly different from that of other veins, being more mas- 

 sive and milky and less drusy, and there is in fact some reason to believe 

 that its mineralization took place a little later than that of the veins 

 following the rhyolite dikes. 



This quartz vein, of very moderate thickness, contains along a well- 

 defined shoot a most remarkably rich bonanza ore, consisting of coarse 

 and hackly pale gold (possibly electrum) firmly imbedded in the white 

 quartz. An interesting characteristic is that within the bonanza shoot 

 rich and barren quartz may intermingle capriciously. The gold is not 

 a secondary deposit; in fact, there is scarcely any evidence at all of such 

 secondary solution and redeposition of the gold by descending surface 

 waters, while there is evidence that some of the silver has been leached 

 by surface waters and redeposited as ruby silver. There is also some 

 secondary marcasite. The shoot has been followed for a distance along 

 the dip of the vein of about 800 feet, the lowest level being opened by a 

 cross cut from Charleston gulch. The production of this extraordinary 

 bonanza since its discovery two years ago is said to have been no less 

 than $2,000,000 up to last fall, mainly in gold. Most of the ore had a 

 tenor of from $10 to $40 per pound. Some high silver values were 

 found at the surface, but the apex of the gold shoot was not encountered 

 until about 60 feet below the surface. No placers have been found in 

 Charleston gulch or in Eight-Mile Creek, in spite of the fact that a 

 great deal of rock has been removed by erosion. Hence it is probable 

 that this gold shoot never reached the surface, and that no other of a 

 similar nature existed within the rock volume carried away by erosion. 

 The almost inevitable conclusion is that such shoots must be scarce below 

 the present surface. 



The exploration of the Noatak River, Alaska: P. S. Smith. 



The 248th meeting was held in the Cosmos Club, November 22, 1911, 

 Vice-President Stanton in the chair. As an informal communication 

 Mr. Robert Anderson gave an account of the formation of a new island 

 two miles off the south coast of Trinidad by an outburst of gas from the 

 Tertiary oil and gas-bearing strata of the submerged coastal shelf. The 

 island is of mud, sand and boulders, is about 10 acres in extent and has 

 a height of 10 or 15 feet above the sea. The later stage of the eruption 

 of this mass was accompanied by a great flame, due to the ignition of the 

 gas. This ignition probably resulted from friction between sulphur- 

 bearing rocks which were shot out. 



REGULAR PROGRAM 



The Carlyle oil field of Illinois: E. W. Shaw. The Carlyle oil field is 

 about forty miles east of St. Louis and was discovered in the spring of 

 1911. It lies about fifteen miles west of the Sandoval oil field which was 

 discovered in 1909. The excitement at Carlyle was intense and fabulous 

 prices were paid for leases on farms which later proved to be outside the 



