John F. Slack
John Slack is a Scientist Emeritus with the USGS Geology, Energy & Minerals (GEM) Science Center in Reston, VA.
Science and Products
Filter Total Items: 69
Map showing lithostratigraphic and structural setting of stratabound (massive) sulfide deposits in the U.S. Appalachians Map showing lithostratigraphic and structural setting of stratabound (massive) sulfide deposits in the U.S. Appalachians
No abstract available.
Authors
Jacob Eugene Gair, John F. Slack
Mineral resources of the Big Frog Wilderness Study Area, Polk County, Tennessee and Fannin County, Georgia Mineral resources of the Big Frog Wilderness Study Area, Polk County, Tennessee and Fannin County, Georgia
The proposed Big Frog Wilderness is comprised of approximately 1820 hectares (18.2 km2) of mountainous terrain in the Cherokee and Chattahoochee National Forests south of the Ocoee River in Polk County, Tennessee, and Fannin County, Georgia. Rocks of the study area are greenschist-facies metasandstone, meta-arkose, metagraywacke, and dark slate of the Ocoee Supergroup of late Precambrian...
Authors
John F. Slack, Gertrude C. Gazdik, Maynard L. Dunn
K-Ar age of alunite alteration at Red Mountain, Lake City area, western San Juan Mountains, Colorado K-Ar age of alunite alteration at Red Mountain, Lake City area, western San Juan Mountains, Colorado
The San Juan Mountains of southwestern Colorado are famous for rich vein deposits of base and precious metals and for patterns of conspicuous hydrothermal alteration. Areas of acid-sulfate alteration, characterized by extensive base leaching of volcanic rocks or hypabyssal plutons, are of current interest because of their local association with Au, Ag, and, in some cases, U...
Authors
Harald H. Mehnert, John F. Slack, Gerald T. Cebula
Geochemical analyses of rock, soil, and stream sediment samples from the Big Frog Wilderness Study Area, Polk County, Tennessee and Fannin County, Georgia Geochemical analyses of rock, soil, and stream sediment samples from the Big Frog Wilderness Study Area, Polk County, Tennessee and Fannin County, Georgia
Semiquantitative spectrographic analyses for 31 elements and atomic absorption analyses for gold and zinc on 43 stream sediments, 5 panned concentrates, 65 soils, and 81 rock samples from the Big Frog Wilderness Study Area and vicinity, Polk County, Tennessee, and Fannin County, Georgia, are reported here in detail. Locations for all 194 samples are given in Universal Transverse Mercator...
Authors
R.T. Hopkins, A.L. Meir, John F. Slack
Mineral resources of the Citico Creek Wilderness Study Area, Monroe County, Tennessee Mineral resources of the Citico Creek Wilderness Study Area, Monroe County, Tennessee
The proposed Citico Creek Wilderness comprises about 5,670 hectares (56.7 km2) in the Cherokee National Forest south of the Little Tennessee River in easternmost Monroe County, Tennessee. Principal drainages are Citico Creek and Doublecamp Creek. Rocks of the study area include greenschist-facies arkosic metasandstone, metagraywacke, slate, and metaconglomerate of the Great Smoky Group...
Authors
John F. Slack, E. R. Force, P. T. Behum, B. B. Williams
The Yellow Dog peridotite and a possible buried igneous complex of lower Keweenawan age in the northern peninsula of Michigan The Yellow Dog peridotite and a possible buried igneous complex of lower Keweenawan age in the northern peninsula of Michigan
Partly serpentinized peridotite of early Keweenawan age crops out in two places along a 20-kilometer-long zone of positive aeromagnetic anomalies in northern Marquette County, Michigan. Most of the area is mantled by Pleistocene drift with few bedrock exposures. Petrographic and electron microprobe studies show that the peridotite was originally a plagioclase lherzolite containing 40 to...
Authors
John S. Klasner, David W. Snider, W.F. Cannon, John F. Slack
Occurrence and formation of avicennite, Tl2O3 , as a secondary mineral at the Carlin gold deposit, Nevada Occurrence and formation of avicennite, Tl2O3 , as a secondary mineral at the Carlin gold deposit, Nevada
Avicennite, Tl2O3, occurs as grains disseminated in silicified limestones in the upper part of the East ore zone of the Carlin gold deposit, Nevada. The avicennite is formed by the oxidation of carlinite, Tl2S, found in primary unoxidized carbonaceous ore immediately below the avicennite. The grains of avicennite closely resemble carlinite in size and shape. Some avicennite occurs as...
Authors
Arthur S. Radtke, Frank W. Dickson, John F. Slack
Premetamorphic hydrothermal origin of the Tungsten Queen vein, Hamme District, North Carolina, as indicated by mineral textures and minor structures Premetamorphic hydrothermal origin of the Tungsten Queen vein, Hamme District, North Carolina, as indicated by mineral textures and minor structures
The Hamme Tungsten district is a 13-km long, 2-km wide, northeast-trending belt located in northern Vance County, North Carolina and southern Mecklenburg County, Virginia (Fig. 1). The district contains the largest quartz-wolframite-type vein deposits in the United States. Over 50 tungsten-bearing veins occur in this area (Espenshade, 1947), from which more than 1 million short ton units...
Authors
Michael P. Foose, John F. Slack
The Yellow Dog peridotite and a possible buried igneous complex of Lower Keweenawan Age in the northern peninsula of Michigan The Yellow Dog peridotite and a possible buried igneous complex of Lower Keweenawan Age in the northern peninsula of Michigan
Partly serpentinized peridotite of early Keweenawan age crops out in two places along a 20-km-long zone of positive aeromagnetic anomalies in northern Marquette County, Michigan. Most of the area is mantled by Pleistocene drift and the bedrock is not exposed. Petrographic and electron microprobe studies show that the peridotite was originally a plagioclase lherzolite containing 40-50%...
Authors
John S. Klasner, David W. Snider, W.F. Cannon, John F. Slack
Science and Products
Filter Total Items: 69
Map showing lithostratigraphic and structural setting of stratabound (massive) sulfide deposits in the U.S. Appalachians Map showing lithostratigraphic and structural setting of stratabound (massive) sulfide deposits in the U.S. Appalachians
No abstract available.
Authors
Jacob Eugene Gair, John F. Slack
Mineral resources of the Big Frog Wilderness Study Area, Polk County, Tennessee and Fannin County, Georgia Mineral resources of the Big Frog Wilderness Study Area, Polk County, Tennessee and Fannin County, Georgia
The proposed Big Frog Wilderness is comprised of approximately 1820 hectares (18.2 km2) of mountainous terrain in the Cherokee and Chattahoochee National Forests south of the Ocoee River in Polk County, Tennessee, and Fannin County, Georgia. Rocks of the study area are greenschist-facies metasandstone, meta-arkose, metagraywacke, and dark slate of the Ocoee Supergroup of late Precambrian...
Authors
John F. Slack, Gertrude C. Gazdik, Maynard L. Dunn
K-Ar age of alunite alteration at Red Mountain, Lake City area, western San Juan Mountains, Colorado K-Ar age of alunite alteration at Red Mountain, Lake City area, western San Juan Mountains, Colorado
The San Juan Mountains of southwestern Colorado are famous for rich vein deposits of base and precious metals and for patterns of conspicuous hydrothermal alteration. Areas of acid-sulfate alteration, characterized by extensive base leaching of volcanic rocks or hypabyssal plutons, are of current interest because of their local association with Au, Ag, and, in some cases, U...
Authors
Harald H. Mehnert, John F. Slack, Gerald T. Cebula
Geochemical analyses of rock, soil, and stream sediment samples from the Big Frog Wilderness Study Area, Polk County, Tennessee and Fannin County, Georgia Geochemical analyses of rock, soil, and stream sediment samples from the Big Frog Wilderness Study Area, Polk County, Tennessee and Fannin County, Georgia
Semiquantitative spectrographic analyses for 31 elements and atomic absorption analyses for gold and zinc on 43 stream sediments, 5 panned concentrates, 65 soils, and 81 rock samples from the Big Frog Wilderness Study Area and vicinity, Polk County, Tennessee, and Fannin County, Georgia, are reported here in detail. Locations for all 194 samples are given in Universal Transverse Mercator...
Authors
R.T. Hopkins, A.L. Meir, John F. Slack
Mineral resources of the Citico Creek Wilderness Study Area, Monroe County, Tennessee Mineral resources of the Citico Creek Wilderness Study Area, Monroe County, Tennessee
The proposed Citico Creek Wilderness comprises about 5,670 hectares (56.7 km2) in the Cherokee National Forest south of the Little Tennessee River in easternmost Monroe County, Tennessee. Principal drainages are Citico Creek and Doublecamp Creek. Rocks of the study area include greenschist-facies arkosic metasandstone, metagraywacke, slate, and metaconglomerate of the Great Smoky Group...
Authors
John F. Slack, E. R. Force, P. T. Behum, B. B. Williams
The Yellow Dog peridotite and a possible buried igneous complex of lower Keweenawan age in the northern peninsula of Michigan The Yellow Dog peridotite and a possible buried igneous complex of lower Keweenawan age in the northern peninsula of Michigan
Partly serpentinized peridotite of early Keweenawan age crops out in two places along a 20-kilometer-long zone of positive aeromagnetic anomalies in northern Marquette County, Michigan. Most of the area is mantled by Pleistocene drift with few bedrock exposures. Petrographic and electron microprobe studies show that the peridotite was originally a plagioclase lherzolite containing 40 to...
Authors
John S. Klasner, David W. Snider, W.F. Cannon, John F. Slack
Occurrence and formation of avicennite, Tl2O3 , as a secondary mineral at the Carlin gold deposit, Nevada Occurrence and formation of avicennite, Tl2O3 , as a secondary mineral at the Carlin gold deposit, Nevada
Avicennite, Tl2O3, occurs as grains disseminated in silicified limestones in the upper part of the East ore zone of the Carlin gold deposit, Nevada. The avicennite is formed by the oxidation of carlinite, Tl2S, found in primary unoxidized carbonaceous ore immediately below the avicennite. The grains of avicennite closely resemble carlinite in size and shape. Some avicennite occurs as...
Authors
Arthur S. Radtke, Frank W. Dickson, John F. Slack
Premetamorphic hydrothermal origin of the Tungsten Queen vein, Hamme District, North Carolina, as indicated by mineral textures and minor structures Premetamorphic hydrothermal origin of the Tungsten Queen vein, Hamme District, North Carolina, as indicated by mineral textures and minor structures
The Hamme Tungsten district is a 13-km long, 2-km wide, northeast-trending belt located in northern Vance County, North Carolina and southern Mecklenburg County, Virginia (Fig. 1). The district contains the largest quartz-wolframite-type vein deposits in the United States. Over 50 tungsten-bearing veins occur in this area (Espenshade, 1947), from which more than 1 million short ton units...
Authors
Michael P. Foose, John F. Slack
The Yellow Dog peridotite and a possible buried igneous complex of Lower Keweenawan Age in the northern peninsula of Michigan The Yellow Dog peridotite and a possible buried igneous complex of Lower Keweenawan Age in the northern peninsula of Michigan
Partly serpentinized peridotite of early Keweenawan age crops out in two places along a 20-km-long zone of positive aeromagnetic anomalies in northern Marquette County, Michigan. Most of the area is mantled by Pleistocene drift and the bedrock is not exposed. Petrographic and electron microprobe studies show that the peridotite was originally a plagioclase lherzolite containing 40-50%...
Authors
John S. Klasner, David W. Snider, W.F. Cannon, John F. Slack