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Composite Sunrise Butte pluton: Insights into Jurassic–Cretaceous collisional tectonics and magmatism in the Blue Mountains Province, northeastern Oregon

The composite Sunrise Butte pluton, in the central part of the Blue Mountains Province, northeastern Oregon, preserves a record of subduction-related magmatism, arc-arc collision, crustal thickening, and deep-crustal anatexis. The earliest phase of the pluton (Desolation Creek unit) was generated in a subduction zone environment, as the oceanic lithosphere between the Wallowa and Olds Ferry island
Authors
Kenneth H. Johnson, J.J. Schwartz, Jiří Žák, Krystof Verner, Calvin G. Barnes, Clay Walton, Joseph L. Wooden, James E. Wright, Ronald W. Kistler

Corrigendum to “Comparing activated alumina with indigenous laterite and bauxite as potential sorbents for removing fluoride from drinking water in Ghana” [Appl. Geochem. 56 (2015) 50–66]

The authors regret that the application of the t-plot to determine the presence of micropores in the three sorbents needs the following corrections: (1) Fig. 1a, c, e are N2(g) adsorption and desorption isotherms” (remove “BET”). This correction applies to descriptions in the text as well. (2) Table 2, the column titled “Micropores” is mislabelled, and should be labelled “Film thickness”, which ma
Authors
Laura Craig, Lisa L. Stillings, David L. Decker, James M. Thomas

Provenance and detrital zircon geochronologic evolution of lower Brookian foreland basin deposits of the western Brooks Range, Alaska, and implications for early Brookian tectonism

The Upper Jurassic and Lower Cretaceous part of the Brookian sequence of northern Alaska consists of syntectonic deposits shed from the north-directed, early Brookian orogenic belt. We employ sandstone petrography, detrital zircon U-Pb age analysis, and zircon fission-track double-dating methods to investigate these deposits in a succession of thin regional thrust sheets in the western Brooks Rang
Authors
Thomas E. Moore, Paul B. O'Sullivan, Christopher J. Potter, Raymond A. Donelick

Structural superposition in fault systems bounding Santa Clara Valley, California

Santa Clara Valley is bounded on the southwest and northeast by active strike-slip and reverse-oblique faults of the San Andreas fault system. On both sides of the valley, these faults are superposed on older normal and/or right-lateral normal oblique faults. The older faults comprised early components of the San Andreas fault system as it formed in the wake of the northward passage of the Mendoci
Authors
Russell W. Graymer, Richard G. Stanley, David A. Ponce, Robert C. Jachens, Robert W. Simpson, Carl M. Wentworth

Lake formation, characteristics and evolution in retroarc deposystems: A synthesis of data from the modern Andean orogen and its associated basins

Lake deposystems are commonly associated with retroarc mountain belts in the geological record. These deposystems are poorly characterized in modern retroarcs, placing limits on our ability to interpret environmental signals from ancient deposits. To address this problem, we have synthesized our existing knowledge about the distribution, morphometrics, and sedimentary geochemical characteristics o
Authors
Andrew S. Cohen, Michael M. McGlue, Geoffrey S. Ellis, Hiran Zani, Peter W. Swarzenski, Mario L. Assine, Aguinaldo Silva

Relationships between protein-encoding gene abundance and corresponding process are commonly assumed yet rarely observed

For any enzyme-catalyzed reaction to occur, the corresponding protein-encoding genes and transcripts are necessary prerequisites. Thus, a positive relationship between the abundance of gene or transcripts and corresponding process rates is often assumed. To test this assumption, we conducted a meta-analysis of the relationships between gene and/or transcript abundances and corresponding process ra
Authors
Jennifer D. Rocca, Edward K. Hall, Jay T. Lennon, Sarah E. Evans, Mark P. Waldrop, James B. Cotner, Diana R. Nemergut, Emily B. Graham, Matthew D. Wallenstein

Truncorotalia crassaformis from its type locality: Comparison with Caribbean plankton and Pliocene relatives

Truncorotalia crassaformis has been identified in Pliocene-Holocene assemblages globally but there has been little analysis of specimens from its type locality at Lomita Quarry, California. This has led to confusion about some diagnostic criteria, particularly the presence of a peripheral keel. To better understand variation specimens are studied from the type locality (Pleistocene, c. 400–600 ka)
Authors
George H. Scott, James C. Ingle, Brendan McCane, Charles L. Powell, Robert C. Thunell

Reconnaissance stratigraphic studies in the Susitna basin, Alaska, during the 2014 field season

The Susitna basin is a poorly-understood Cenozoic successor basin immediately north of Cook Inlet in south-central Alaska (Kirschner, 1994). The basin is bounded by the Castle Mountain fault and Cook Inlet basin on the south, the Talkeetna Mountains on the east, the Alaska Range on the north, and the Alaska–Aleutian Range on the west (fig. 2-1). The Cenozoic fill of the basin includes coal-bearing
Authors
David L. LePain, Richard G. Stanley, Nina T. Harun, Kenneth P. Helmold, Rebekah Tsigonis

Reconnaissance coal study in the Susitna basin, 2014

The Alaska Division of Geological & Geophysical Surveys (DGGS) conducted fieldwork during the summer of 2014 in the Susitna basin as part of an ongoing evaluation of the hydrocarbon potential of frontier basins, particularly those near the Railbelt region (for example, Decker and others, 2013; Gillis and others, 2013). Topical studies associated with this recent work include sedimentary facies ana
Authors
Nina T. Harun, David L. LePain, Rebekah Tsigonis, Kenneth P. Helmold, Richard G. Stanley

Magmatism, metasomatism, tectonism, and mineralization in the Humboldt Range, Pershing County, Nevada

Introduction The Humboldt Range, Pershing County, Nevada, predominantly consists of Mesozoic igneous and sedimentary rocks that were modified several times by magmatism, metasomatism, and tectonism, and contain a variety of metallic (Ag, Au, Pb, Zn, Sb, W, Hg) and non-metallic (dumortierite, pinite, fluorite) mineral deposits (Knopf, 1924; Kerr and Jenney, 1935; Kerr, 1938; Cameron, 1939; Campbe
Authors
Peter G. Vikre

Lateritic, supergene rare earth element (REE) deposits

Intensive lateritic weathering of bedrock under tropical or sub-tropical climatic conditions can form a variety of secondary, supergene-type deposits. These secondary deposits may range in composition from aluminous bauxites to iron and niobium, and include rare earth elements (REE). Over 250 lateritic deposits of REE are currently known and many have been important sources of REE. In southeastern
Authors
Mark D. Cocker