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Ogden, UT, United States

Weber State University /ˈwiːbər/ is a public university in Ogden city in Weber County, Utah, USA. It is a coeducational, publicly supported university offering professional, liberal arts and technical certificates, as well as associate, bachelor's and master's degrees. Weber State University is accredited by the Northwest Commission on Colleges and Universities. Programs throughout the university are accredited as well.The school was founded in 1889 by The Church of Jesus Christ of Latter-day Saints as Weber Stake Academy, later changing names to Weber Academy, Weber Normal College, and Weber College. Weber College became a junior college in 1933, and in 1962 became Weber State College. It gained university status in 1991, when it was renamed to its current name of Weber State University. Wikipedia.

Yonkee A.,Weber State University | Weil A.B.,Bryn Mawr College
Bulletin of the Geological Society of America | Year: 2010

Analyses of mesoscopic structural and strain patterns in red beds of the Triassic Ankareh Formation and limestones of the Jurassic Twin Creek Formation, in concert with complementary paleomagnetic studies, constrain the three-dimensional kinematic evolution of curved fold-and-thrust systems in the Wyoming salient of the Sevier thrust belt. Spaced cleavage, fracture and vein networks, minor folds, and minor faults in limestones and red beds accommodated early layer-parallel shortening (LPS) concentrated in front of the growing thrust wedge, along with minor strike-parallel extension and wrench shear related to the development of orogenic curvature. Strain, estimated using mass balance relations for cleavage seams, crinoid ossicles in bioclastic limestone, and reduction spots in red beds, displays systematic regional patterns. Principal shortening directions are subperpendicular to structural trend around the salient, reflecting a combination of primary curvature and secondary rotation of early LPS fabrics. LPS magnitudes vary from <5% in central parts of the frontal Hogsback thrust system, where cleavage is absent, to 10%-30% in the more interior Crawford thrust system, where cleavage intensity is moderate to strong; strain also increases toward the salient ends. Internal strain is a significant component of total deformation and should be considered when restoring cross sections. Strain patterns are consistent with a kinematic model involving curved fault slip and differential shortening that produced progressive secondary curvature during thrusting. © 2009 Geological Society of America. Source

Weil A.B.,Bryn Mawr College | Yonkee W.A.,Weber State University
Earth and Planetary Science Letters | Year: 2012

Varying patterns of layer-parallel shortening (LPS) and vertical-axis rotations from the thin-skin Sevier fold-thrust belt to the thick-skin Laramide foreland of Wyoming are quantified from integrated structural, anisotropy of magnetic susceptibility (AMS), and paleomagnetic analyses. Within the Sevier belt, widespread early LPS was accommodated by spaced cleavage, fracture sets, minor folds, and minor faults. LPS directions are subperpendicular to structural trends of systematically curved thrust sheets of the Wyoming salient, reflecting a combination of primary dispersion and secondary rotation during thrusting. Within the Laramide foreland, limited LPS was accommodated mostly by minor faults with conjugate wedge and strike-slip geometries. LPS directions in gentler fold limbs vary from perpendicular to acute with structural trends of variably oriented, anastomosing basement-cored arches. Steep forelimbs display more complex relations, including younger fault sets that developed during evolving stress states and localized vertical-axis rotations. Although internal strain is limited, weak AMS lineations defined by kinked and rotated phyllosilicates are widely developed and consistently oriented perpendicular to measured LPS directions. Palinspastically restored LPS directions, corrected for paleomagnetically determined vertical-axis rotations, vary on average from W-E in the Sevier belt to WSW-ENE in the Laramide foreland. In detail, LPS directions display deflections related to primary sedimentary wedge geometry and basement fabrics. LPS in the Sevier belt is interpreted to partly reflect stress transmitted from the hinterland through the growing orogenic wedge and topographic stress along the front of the wedge. LPS in the Laramide foreland is interpreted to partly reflect basal traction during flat-slab subduction beneath thick cratonic lithosphere, with spatial-temporal variations in stress trajectories related to basement heterogeneities and evolving fault systems. Evidence for significant late N-S Laramide shortening, as proposed by multi-stage shortening models, is not observed. © 2012 Elsevier B.V. Source

Heller R.,McMaster University | Armstrong J.,Weber State University
Astrobiology | Year: 2014

To be habitable, a world (planet or moon) does not need to be located in the stellar habitable zone (HZ), and worlds in the HZ are not necessarily habitable. Here, we illustrate how tidal heating can render terrestrial or icy worlds habitable beyond the stellar HZ. Scientists have developed a language that neglects the possible existence of worlds that offer more benign environments to life than Earth does. We call these objects " superhabitable" and discuss in which contexts this term could be used, that is to say, which worlds tend to be more habitable than Earth. In an appendix, we show why the principle of mediocracy cannot be used to logically explain why Earth should be a particularly habitable planet or why other inhabited worlds should be Earth-like. Superhabitable worlds must be considered for future follow-up observations of signs of extraterrestrial life. Considering a range of physical effects, we conclude that they will tend to be slightly older and more massive than Earth and that their host stars will likely be K dwarfs. This makes Alpha Centauri B, which is a member of the closest stellar system to the Sun and is supposed to host an Earth-mass planet, an ideal target for searches for a superhabitable world. Key Words: Extrasolar terrestrial planets-Extraterrestrial life-Habitability-Planetary environments-Tides. Astrobiology 14, 50-66. © 2014 Mary Ann Liebert, Inc. Source

A concentration of lake/playa basins occurs on the Southern High Plains (SHP) of northwest Texas and eastern New Mexico. Associated with these lake/playas are lee-side lunettes positioned on their southeast margins ranging in height from 1.5 to >10 m. An OSL dating program was applied to 30 samples from lunettes associated with large lakes and small playa basins. Samples were extracted from trenched dune sections or from deep cores. Earlier SHP lunette investigations show depositional ages primarily in the late Wisconsin and Holocene. This research extends the timing of lunette accretion to the middle Pleistocene, the earliest recorded deposition for these features. The expanded chronology permitted investigation into dune morphology on nested lunettes built on contracting lake margins. Outer lunettes formed prior to inner dunes, but simultaneous deposition occurred on downwind ridges as younger lee-side dunes were constructed. Large lake lunettes were inactive during discreet SHP pluvial episodes from early Wisconsin to LGM. Conversely, these lunettes accreted when climatic conditions promoted basin desiccation and aeolian deflation. This suggests their mode of formation contrasts with lunette models recognized for other regions. From post LGM to earliest Holocene, active lunette accretion occurred from 16 to 11 ka followed by a significant period of lunette construction during the mid-Holocene. Late Holocene-lunette deposition was interrupted by intervals of landscape stability. Lunette deposition between 1300s and 1700s corresponds with drought intervals recognized in tree-ring records from adjacent regions. Recent lunette activity on the plateau is contemporary with the 1930's 'dust bowl'. Further insight into SHP response to changing climatic conditions was given by comparing lunette depositional events with previous investigations on sedimentation intervals for draws, lake/playa basins, and sand sheets. © 2012 Elsevier Ltd. Source

Zeng G.L.,Weber State University
Medical physics | Year: 2013

This aim of this paper is to revisit the parallel-beam/cone-beam or fan-beam/cone-beam imaging configuration, and to investigate whether this configuration has any advantages. Twenty years ago, it was suggested to simultaneously use a parallel-beam (or a fan-beam) collimator and a cone-beam collimator to acquire single photon emission computed tomography data. The motivation was that the parallel-beam (or the fan-beam) collimator can provide sufficient sampling, while the cone-beam collimator is able to provide higher photon counts. Even with higher total counts, this hybrid system does not give significant improvement (if any) in terms of image noise and artifacts reduction. If a conventional iterative maximum-likelihood expectation-maximization algorithm is used to reconstruct the image, the resultant reconstruction may be worse than the parallel-beam-only (or fan-beam-only) system. This paper uses the singular value decomposition (SVD) analysis to explain this phenomenon. The SVD results indicate that the parallel-beam-only and the fan-beam-only system outperform the combined systems. The optimal imaging system does not necessary to be the one that generates the projections with highest signal-to-noise ratio and best resolution. Source

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