Publications
Filter Total Items: 1147
Fluorine
Fluorine compounds are essential in numerous chemical and manufacturing processes. Fluorspar is the commercial name for fluorite (isometric CaF2), which is the only fluorine mineral that is mined on a large scale. Fluorspar is used directly as a fluxing material and as an additive in different manufacturing processes. It is the source of fluorine in the production of hydrogen fluoride or hydrofluo
Authors
Timothy S. Hayes, M. Michael Miller, Greta J. Orris, Nadine M. Piatak
Rhenium
Rhenium is one of the rarest elements in Earth’s continental crust; its estimated average crustal abundance is less than 1 part per billion. Rhenium is a metal that has an extremely high melting point and a heat-stable crystalline structure. More than 80 percent of the rhenium consumed in the world is used in high-temperature superalloys, especially those used to make turbine blades for jet aircra
Authors
David John, Robert R. Seal, Désirée E. Polyak
Platinum-group elements
The platinum-group elements (PGEs)—platinum, palladium, rhodium, ruthenium, iridium, and osmium—are metals that have similar physical and chemical properties and tend to occur together in nature. PGEs are indispensable to many industrial applications but are mined in only a few places. The availability and accessibility of PGEs could be disrupted by economic, environmental, political, and social e
Authors
Michael L. Zientek, Patricia J. Loferski, Heather L. Parks, Ruth F. Schulte, Robert R. Seal
Punctuated sediment discharge during early Pliocene birth of the Colorado River: Evidence from regional stratigraphy, sedimentology, and paleontology
The Colorado River in the southwestern U.S. provides an excellent natural laboratory for studying the origins of a continent-scale river system, because deposits that formed prior to and during river initiation are well exposed in the lower river valley and nearby basinal sink. This paper presents a synthesis of regional stratigraphy, sedimentology, and micropaleontology from the southern Bouse Fo
Authors
Rebecca J. Dorsey, Brennan O’Connell, Kristin McDougall-Reid, Mindy B. Homan
Ore-forming adakitic porphyry produced by fractional crystallization of oxidized basaltic magmas in a subcrustal chamber (Jiamate, East Junggar, NW China)
Adakitic intrusions are supposed to have a close genetic and spatial relationship to porphyry Cu deposits. However, the genesis of adakitic intrusions is still under dispute. Here, we describe newly discovered intrusive complex rocks, which are composed of ore-bearing, layered magnetite-bearing gabbroic and adakitic rocks in Jiamate, East Junggar, NW China. These Jiamate Complex intrusions have di
Authors
Tao Hong, Xing-Wang Xu, Jungang Gao, Stephen Peters, Di Zhang, Reyaniguli Jielili, Peng Xiang, Hao Li, Chu Wu, Jun You, Jie Liu, Qiang Ke
Natural inquirer: The citizen science edition
People across the world are helping scientists collect data to answer important research questions. Learn how citizens are getting involved in science, from counting birds and lionfish to reporting earthquakes. All Over the Map, Citizen Science System, Device-ive Science, Invasion of the Song Snatcher, and Lion In Wait.
Authors
Shonté Jenkins
Geologic sources of energy
This chapter describes the exploration, development, and geologic setting of petroleum resources (including tar sands), coal resources (including coalbed methane), and geothermal energy resources of the Northern Cordillera.For petroleum resources, the chapter describes: (1) the history of petroleum development and production, first for Alaska and then for the Canadian Cordillera; and (2) generaliz
Authors
Thomas K. Bundtzen, Warren J. Nokleberg
The late Cenozoic Eastern California Shear Zone after 25 years of study
No abstract available.
Authors
David M. Miller
Mineralogical characterization of weathered outcrops as a tool for constraining water chemistry predictions during project planning
Weathered samples from naturally exposed outcrops of troctolite associated with a magmatic
Ni-Cu sulphide deposit were characterized by synchrotron-based micro-X-ray fluorescence mapping
(µ-XRF) and X-ray absorption spectroscopy (XAS), as well as by lab-based X-ray diffraction, electron
microscopy, Raman spectroscopy and wet chemical methods. Metal mobility in weathered samples
was assessed using
Authors
Tamara Diedrich, Paul Fix, Andrea L. Foster
Geochemical variations during development of the 5.46 Ma Broadwell Mesa basaltic volcanic field, California
The 5.46±0.04 Ma Broadwell Mesa basalt and associated basaltic volcanic field in the western Bristol Mountains, California, formed a ~6 km2 volcanic flow field with architecture including numerous lava flows, a ~1.1 km2 lava lake, and a ~0.17 km2 cinder cone. The local number of lava flows varies from one along the margins of the field to as many as 18 that are stacked vertically, onlapped by you
Authors
David C. Buesch
Connecting the Soda–Avawatz and Bristol–Granite Mountains faults with gravity andaeromagnetic data, Mojave Desert, California
The Soda–Avawatz and Bristol–Granite Mountains faults are considered by some to form the northeastern margin of the eastern California shear zone yet their connectivity and extents are obscured by surficial deposits and the estimates of total right-lateral offset from geologic data range from 0 to as much as 24 km. We use gravity and recently released detailed aeromagnetic data to map strands of t
Authors
Victoria E. Langenheim, David M. Miller