Geological Classification of Canadian Gold Deposits

Geological Classification of Canadian Gold Deposits PDF

Author: Knud Howard Poulsen

Publisher:

Published: 2000

Total Pages: 116

ISBN-13:

DOWNLOAD EBOOK →

This bulletin proposes a geological classification of lode gold deposits based largely on the nature of the ore and on the geological settings of the deposits. Sixteen common types of bedrock gold deposits are distinguished and their main geological attributes are summarized. These do not correspond to an equal number of genetic types; many of these deposit types represent different components of larger hydrothermal systems and are genetically related. Most of the deposit types identified are represented by at least one large example (containing over 100 tonnes of gold). Descriptions are provided of Canadian gold deposits, including Archean & Proterozoic deposits in the Canadian Shield, Late Proterozoic to Palaeozoic deposits in the Appalachian Orogen, and Mesozoic to Cenozoic deposits in the Cordilleran Orogen. The final section discusses the application of gold deposit models.

The Metallogeny of Lode Gold Deposits

The Metallogeny of Lode Gold Deposits PDF

Author: Ulrich Kretschmar

Publisher: Elsevier

Published: 2015-11-24

Total Pages: 350

ISBN-13: 0128032235

DOWNLOAD EBOOK →

The Metallogeny of Lode Gold Deposits: A Syngenetic Perspective is a synthesis of lode gold vein forming processes, addressing the commonality in similar worldwide deposits. The book’s empirical model incorporates widely known and accepted principles of ore deposition and shows how it applies in the volcanic-sedimentary greenstone belt environment. Several chapters detail outcrop maps and photos of field occurrences and textures. The interpretations flow directly from the authors’ field work, and are coupled with analyses of underlying physical processes. Utilizing detailed geological mapping, field work, and chemical analyses as the basis of a syngenetic formation mode, the text arms readers with the tools necessary to accurately analyze and interpret new data on the subject. This includes information on decoding the significance of asymmetry in vein formation, as well as the role of lamprophyres in gold camps, how Archean geology requires integration into a lode vein formation model, and how to develop an understanding of the worldwide applicability of gold cycles to lode vein formation and exploration and how it can be applied to deposits of all ages. Presents the first book to galvanize lode gold research into a single authoritative reference Simplifies the complexity of lode gold’s underlying processes and presents valid concepts surrounding the lode gold forming environment Features color figures, illustrations, and photos that enrich the content’s focus and aid in the retention of key concepts

A Regional Structural Model for Gold Mineralization in the Southern Part of the Archean Superior Province, United States

A Regional Structural Model for Gold Mineralization in the Southern Part of the Archean Superior Province, United States PDF

Author: Paul Kibler Sims

Publisher:

Published: 1992

Total Pages: 28

ISBN-13:

DOWNLOAD EBOOK →

The Canadian segment of the Archean Superior province is a major world source of lode gold. The gold deposits occur in or near regional transcurrent and oblique slip-shear deformation zones that comprise a conjugate set to a northwest- directed compression of the Superior province. These structures provided permeable pathways for the flow of large volumes of auriferous fluid derived from an external source. Historic gold production from the United States segment of the Superior province is modest, but the close similarity in the geologic environment of the United States and Canadian segments suggests that large gold deposits should be present in the U.S.A. An occurrence model largely based on known parameters of gold mineralization in Canada suggests that the greenstone-granite terranes of the Wawa and Wabigoon sub-provinces in the United States are favorable for important gold deposits. The model suggests that gold mineralization took place during or later than the transcurrent faulting and that it took place contemporaneously with emplacement of silica-undersaturated intrusions. The faulting occurred late in the igneous-tectonic history of the Superior province, about 2,690 Ma. Extensive, intense alteration comprising carbonitization, silicification, and sulfidization accompanied the gold mineralization. The relationships between alteration minerals and mineralized veins suggest a close temporal relationship between the alteration and gold mineralization processes. The proposed occurrence model for gold mineralization and the available data suggest that two broad regions of greenstone in the Archean Superior province in north-central United States are particularly favorable for gold deposits: (1) the Upper Peninsula of Michigan, and (2) northeastern Minnesota. The Ishpeming greenstone belt of the Wawa subprovince in Michigan contains the important Ropes deposit and several other known gold occurrences, and the Vermilion district (Wawa subprovince) in northeastern Minnesota contains highly anomalous gold in soils and minor known bedrock occurrences. Transcurrent faults in both areas should be favorable sites for gold mineralization

Lanterna Rally - Theme by Grace Themes