thumbnail

Geologic setting of the lead and zinc deposits, Drenchwater Creek area, Howard Pass Quadrangle, Western Brooks Range, Alaska

Open-File Report 78-70-C
By:  and 
https://doi.org/10.3133/ofr7870C

Links

Abstract

Significant concentrations of galena, sphalerite, and minor barite are present in the Drenchwater Creek area, Howard Pass quadrangle, western Brooks Range, Alaska. Detailed geologic mapping indicates that galena, sphalerite and pyrite occur sporadically in a zone at least 1,830 m. long and 6-30 m. wide. The sulfides occur in tuff, or in dark chert and dark shale adjacent to tuff in the upper part of the Lisburne Group of Mississippian age. The sulfides, together with the tuff, dark shale, and dark chert host, rocks probably are part of a stratiform, massive sulfide deposit that may have formed from volcanic exhalations. The stratiform occurrence of the sulfides is limited to a single thrust plate which is a part of a widespread tectonic breccia. The deposit may represent a fragment of a much more extensive stratiform deposit that was severely disrupted and dismembered by isoclinal folding, faulting and shearing. Other areas along the northern front of the Brooks Range particularly those associated with iron staining and the assemblage of dark chert, dark shale and tuff of the Lisburne Group should be examined for concentrations of galena and sphalerite. Because of the highly deformed nature of the terrain, further exploration should concentrate either on finding the edges of buried, dismembered fragments of the original stratiform deposit or on geophysical techniques that may locate the dismembered fragments at depth.

Study Area

Publication type Report
Publication Subtype USGS Numbered Series
Title Geologic setting of the lead and zinc deposits, Drenchwater Creek area, Howard Pass Quadrangle, Western Brooks Range, Alaska
Series title Open-File Report
Series number 78-70
Chapter C
DOI 10.3133/ofr7870C
Year Published 1978
Language English
Publisher U.S. Geological Survey
Description Report: 16 p.; 1 Plate: 39.74 x 32.95 inches
Country United States
State Alaska
Other Geospatial Howard Pass Quadrangle, Western Brooks Range
Google Analytic Metrics Metrics page
Additional publication details