Online courses can feel isolating and sometimes lack human connections that motivate students. We developed a fully online geoscience course to build 'Community of Inquiry' with attention cognitive, social, teaching presences. ran the using nearly identical materials for 8 semesters (recorded video lectures, labs, assignments, assessments). Slight variations in instructor behavior caused profound impacts on student performance, creating natural experiment isolate factors influence...

Research Article| August 01, 1996 Formation of aragonite cement by nannobacteria in the Great Salt Lake, Utah Vicki A. Pedone; Pedone 1Department Geological Sciences, California State University, Northridge, 91330-8266 Search for other works this author on: GSW Google Scholar Robert L. Folk 2Department University Texas at Austin, 71713-7909 Author and Article Information Publisher: Society America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print 0091-7613 Geology (1996) 24 (8):...

Abstract An integrated petrographic and spectroscopic (X‐ray diffraction, phosphor imaging synchrotron X‐ray absorption spectroscopy) study of tufas from the Miocene Barstow Formation, California, relates sample morphology, mineralogy geochemical composition. The tufas, composed mainly calcite that formed at interface between an ancient alkaline lake ground or spring waters, have textures similar to those microbially mediated terrestrial stromatolites travertines. elevated concentrations a...

Research Article| March 01, 2005 Using U-Pb ages of Miocene tufa for correlation in a terrestrial succession, Barstow Formation, California Jennifer M. Cole; Cole 1Interdepartmental Doctoral Program Anthropological Sciences, State University New York at Stony Brook, 11794-4364, USA Search other works by this author on: GSW Google Scholar E. Troy Rasbury; Rasbury 2Department Geosciences, 11794-2100, Gilbert N. Hanson; Hanson Isabel P. Montañez; Montañez 3Department Geology, California, Davis,...

The Cadjebut Zn-Pb deposit is one of several Mississippi Valley-type resources hosted in Devonian carbonates the Lennard shelf, Western Australia. Several dolomitization events and at least three pulses mineralization are documented area, indicating multiple episodes fluid expulsion during basin evolution. data contrast with previous models which propose a single event for shelf.Two major recorded area. earlier more weakly developed characterized by finely crystalline sphalerite marcasite...

ABSTRACT Fabric-preserving quasi-rhombohedral dolomite forms as cement and replacement of aragonite in a tufa mound 2+ m thick on the western shoreline Great Salt Lake. The rounded crystals range size from 5 to 20 µm diameter. Crystal faces are not pitted have numerous sharp-edged steps kinks. result crystal-growth phenomena post-crystallization dissolution. Microprobe analyses (n = 92) yield an average 46 mole % MgCO3, agreement with 44 45 MgCO3 content determined x-ray diffraction (30.8° 2...

Research Article| February 01, 2001 Cyclic variations of uranium concentrations and oxygen isotopes in tufa from the middle Miocene Barstow Formation, Mojave Desert, California Mona L. Becker; Becker 1Department Geosciences, State University New York, Stony Brook, York 11794-2100, USA Search for other works by this author on: GSW Google Scholar Jennifer M. Cole; Cole 2Interdepartmental Doctoral Program Anthropological Sciences, 11794-4364, E. Troy Rasbury; Rasbury 3Department Vicki A....

Promoting collaboration and discourse in asynchronous online courses is challenging; students need something engaging to talk about, a communications medium which fluidly discuss it, social environment that supports discourse. We designed fully introductory geoscience lecture lab course called Geology Goes Hollywood emphasizes all three of the dimensions community inquiry framework: cognitive presence, teaching presence. To heighten we pair movies with documentaries about issues relevant...

ABSTRACT A Late Pleistocene carbonate microbialite complex at Death Point on the western shore of Great Salt Lake, UT, USA, coats Paleozoic bedrock over an area 70 × 40 m. The largely formed while Lake Bonneville flooded basin. Three distinct stratigraphic units separated by minor unconformities have been identified. oldest unit (Unit 1) occurs entire outcrop and ranges from 10 cm to 2.5 m in thickness. It precipitated as aragonite wave‐agitated shoreline environment during early...

Abstract Radiocarbon and uranium-thorium dating of microbialites penecontemporaneous cements in a microbialite mound at Death Point Lakeside, Utah, on the shore Great Salt Lake, call for revision Lake Bonneville hydrograph. At about 30,000 cal yr BP, lake experienced an abrupt rise 20 m, then dropped back down to levels near or slightly higher than modern average elevation Lake. Over ensuing ~6000 series fluctuations, up few tens meters again. The exact timing amplitudes those fluctuations...

SummaryAt least four petrographically, geochemically, temporally and spatially distinct dolomites have been identified in mid-late Devonian carbonate banks reefal buildups of the Emanuel Range on south eastern Lennard Shelf. Detailed mapping dolomite bodies their relationship to extensional faults MVT-sulphide mineralisation has allowed structural evolution southeastern be reconstructed providing constraints range during oil migration MVT mineralisation.The earliest (DI) is a...

Abstract Retention is a major problem for engineering majors, including Electrical and Computer Engineering students. Multiple factors contribute to retention issues, such as poor teaching advising, the difficulty of curriculum, lack motivation resulting from connections community. Statistics indicate large drop in continuation rate between first third years among Science, Technology, Engineering, Math (STEM) As students encounter increasing course early stages their programs, they often...

Mirzaei has worked as an application engineer for six years from 2000 to 2005 with focus on problem solving and resolving design issues regards