Mineral Resources Program
U.S. Geological Survey Mineral Resources ProgramMineral resource science supporting informed decisionmaking
Geologic map of the Fort Collins 30'×60' quadrangle, Larimer and Jackson Counties, Colorado, and Albany and Laramie Counties, Wyoming
The rocks and landforms of the Fort Collins 30′ × 60′ 1:100,000-scale U.S. Geological Survey quadrangle reveals a particularly complete record of geologic history in the northern Front Range of Colorado. The Proterozoic basement rocks exposed in the core of the range preserve evidence of Paleoproterozoic marine sedimentation, volcanism, and...Workman, Jeremiah B.; Cole, James C.; Shroba, Ralph R.; Kellogg, Karl S.; Premo, Wayne R.
Descriptive models for epithermal gold-silver deposits: Chapter Q in
Epithermal gold-silver deposits are vein, stockwork, disseminated, and replacement deposits that are mined primarily for their gold and silver contents; some deposits also contain substantial resources of lead, zinc, copper, and (or) mercury. These deposits form in the uppermost parts of the crust, at depths less than about 1,500 meters below the...John, David A.; Vikre, Peter G.; du Bray, Edward A.; Blakely, Richard J.; Fey, David L.; Rockwell, Barnaby W.; Mauk, Jeffrey L.; Anderson, Eric D.; Graybeal, Frederick T.
Understanding the captivity effect on invertebrate communities transplanted into an experimental stream laboratory
Little is known about how design and testing methodologies affect the macroinvertebrate communities that are held captive in mesocosms. To address this knowledge gap, we conducted a 32‐d test to determine how seeded invertebrate communities changed once removed from the natural stream and introduced to the laboratory. We evaluated larvae survival...Schmidt, Travis S.; Rogers, Holly; Miller, Janet L.; Mebane, Christopher A.; Balistrieri, Laurie S.
Distinguishing brackish lacustrine from brackish marine deposits in the stratigraphic record: A case study from the late Miocene and early Pliocene Bouse Formation, Arizona and California, USA
Brackish marine and brackish continental environments are fundamentally different from a compositional perspective. Brackish water is often defined as having salinity lower than that of standard seawater but higher than that of freshwater, but less regard is given to the origin of the salts involved. The simple dilution of...Bright, Jordon; Cohen, Andrew S.; Starratt, Scott W.
Paleoseismic results from the Alpine site, Wasatch fault zone: Timing and displacement data for six holocene earthquakes at the Salt Lake City–Provo segment boundary
To improve the characterization of Holocene earthquakes on the Wasatch fault zone (WFZ), we conducted light detection and ranging (lidar)‐based neotectonic mapping and excavated a paleoseismic trench across an 8‐m‐high fault scarp near Alpine, Utah, located <1  km"><1 km<1 km south of the boundary...Bennett, Scott E. K.; Duross, Christopher; Gold, Ryan D.; Briggs, Richard; Personius, Stephen; Reitman, Nadine G.; Devore, Joshua; Hiscock, Adam; Mahan, Shannon A.; Gray, Harrison; Gunnarson, Sydney; Stephenson, William J.; Pettinger, Elizabeth; Odum, Jackson K.
Aeromagnetic map of Mountain Pass and vicinity, California and Nevada
Magnetic investigations of Mountain Pass and vicinity were begun as part of an effort to study regional crustal structures as an aid to understanding the geologic framework and mineral resources of the eastern Mojave Desert. The study area, which straddles the state boundary between southeastern California and southern Nevada, encompasses Mountain...Ponce, David A.; Ponce, David A.; Denton, Kevin M.
Isostatic gravity map of Mountain Pass and vicinity, California and Nevada
Gravity investigations of Mountain Pass and vicinity were begun as part of an effort to study regional crustal structures as an aid to understanding the geologic framework and mineral resources of the eastern Mojave Desert. The study area, which straddles the state boundary between southeastern California and southern Nevada, encompasses Mountain...Ponce, David A.; Ponce, David A.; Denton, Kevin M.
Geophysical and geologic maps of Mountain Pass and vicinity, California and Nevada
U.S. Geological Survey Scientific Investigations Map 3412 is a series of products that consists of geophysical and geologic maps of Mountain Pass and vicinity, California. Maps A and B (red outline in above map image) are gravity and aeromagnetic maps, respectively. The map series was begun as part of an effort to study regional crustal structures...Ponce, David A.
Interpretation of low‐temperature thermochronometer ages from tilted normal fault blocks
Low‐temperature thermochronometry is widely used to measure the timing and rate of slip on normal faults. Rates are often derived from suites of footwall thermochronometer samples, but regression of age vs. structural depth fails to account for the trajectories of samples during fault slip. We demonstrate that in rotating fault blocks, regression...Johnstone, Samuel A.; Colgan, Joseph P.
Controls on submarine channel-modifying processes identified through morphometric scaling relationships
Submarine channels share morphological similarities with rivers, but observations from modern and ancient systems indicate they are formed under processes and controls unique to submarine settings. Morphologic characteristics of channels—e.g., width, depth, slope, and the relationships among them—can constrain interpretations of channel-forming...Shumaker, Lauren E.; Jobe, Zane R.; Johnstone, Samuel A.; Pettinga, Luke A.; Cai, Dingxin; Moody, Jeremiah D.
Thermally induced fracture of macroscale surficial granite sheets
Geologically diverse landforms around the world show indications of energetic macroscale fracture. These fractures are sometimes displayed dramatically as so-called “A-tents”, whereby relatively thin rock sheets push upwards and fracture, forming tent-like voids beneath the ruptured sheets. The origin and formation of such features has been a...Collins, Brian D.; Stock, Greg M.; Eppes, Martha C.
Geologic map of the Castle Rock 7.5' quadrangle, Arizona and California
The Castle Rock quadrangle is in the northeast corner of Chemehuevi Valley, California and Arizona. It includes the Colorado River’s entrance to the valley at the mouth of Topock Gorge and the northern outskirts of Lake Havasu City, Arizona, and the Chemehuevi Indian Tribe community of Havasu Lake, California. The map includes large parts of the...House, P. Kyle; John, Barbara E.; Malmon, Daniel V.; Block, Debra; Beard, L. Sue; Felger, Tracey J.; Crow, Ryan S.; Schwing, Jonathan E.; Cassidy, Colleen E.