U.S. Geological Survey Bulletin


Book Description

This history of placer mining of the gold deposits of east central Alaska, near the town of Circle, covers its development from 1893 to date and includes a summary of the regional geology and of the gravels of each creek.
















Literature Recommendations


Book Description




Bitumens in Ore Deposits


Book Description

This volume covers the occurrence, interpretation and significance of bitumens (hydrocarbon residues) in ore deposits. Bitumens occur with a wide variety of ores, including deposits of base metals, mercury, uranium, gold and other precious metals. The papers included reflect this variety of bitumen occurrences and the potential for obtaining useful data from them. The contributions are written by acknowledged experts in this field, who cover analytical techniques and case studies using diverse petrographic and geochemical approaches which will give ore geologists and geochemists an excellent insight into the interpretation of bitumens during mineral exploration. The large number of plates in particular will help the non-specialist to make good use of the volume through the application to new deposits. This is the most comprehensive set of contributions published on a subject of growing interest; at a time when explorationists are increasingly recognising the occurrence of bitumens in ore deposits and the fact that the evolution of mineralising fluids and hydrocarbon fluids may be closely interlinked.