Physical Sciences and Mathematics Commons^™

The Birth Of A Forearc: The Basal Great Valley Group, California, Usa, D. A. Orme, Kathleen D. Surpless

Kathleen D. Surpless

The Great Valley basin of California (USA) is an archetypal forearc basin, yet the timing, structural style, and location of basin development remain controversial. Eighteen of 20 detrital zircon samples (3711 new U-Pb ages) from basal strata of the Great Valley forearc basin contain Cretaceous grains, with nine samples yielding statistically robust Cretaceous maximum depositional ages (MDAs), two with MDAs that overlap the Jurassic-Cretaceous boundary, suggesting earliest Cretaceous deposition, and nine with Jurassic MDAs consistent with latest Jurassic deposition. In addition, the pre-Mesozoic age populations of our samples are consistent with central North America sources and do not require a …

Temperaments And Learning Styles Vs. Academic Performance Of First-Semester Physics Students, Shel Randall

Shel Randall

The Diseños Project: A Geospatial Visualization Of The Environmental History Of California, 1769-1892, Rubén Mendoza

Rubén Mendoza

No abstract provided.

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.

Hornbrook Formation, Oregon And California: A Sedimentary Record Of The Late Cretaceous Sierran Magmatic Flare-Up Event, Kathleen D. Surpless

Kathleen D. Surpless

Early Late Cretaceous time was characterized by a major magmatic flare-up event in the Sierra Nevada batholith and early phases of magmatism in the Idaho batholith, but the sedimentary record of this voluminous magmatism in the U.S. Cordillera is considerably less conspicuous. New detrital zircon U-Pb ages from the Hornbrook Formation in southern Oregon and northern California reveal a significant and sustained influx of 100–85 Ma detrital zircons into the broader Hornbrook region beginning ca. 90 Ma. Detrital zircon ages and hafnium isotopic compositions, combined with whole-rock geochemistry, suggest that sediment was largely derived from the Sierra Nevada, requiring uplift …

A Fishery, A Sanctuary, A Sink, And A Disaster: The Often Hapless Management Of California's Salton Sea, William M. Mclaren

Will McLaren

Over a century ago, a series of questionable management decisions and water-diversion engineering mistakes in Southern California produced an “unnatural” waterbody called the Salton Sea. Since then, the Sea has served as a recreational destination with fluctuating popularity, a sanctuary for migratory birds, a sink for agricultural runoff and urban wastewater, and one of the most productive tilapia and corvina fisheries in the United States. However, the Sea’s resources and associated uses have steadily deteriorated since its formation.

The contrast between the ethics that drove resource management decisions at the time of the Salton Sea’s formation to those employed in …

In The Heat Of The Law, It's Not Just Steam: Geothermal Resources And The Impact On Thermophile Biodiversity, Donald J. Kochan, Tiffany Grant

Donald J. Kochan

Significant research has been conducted into the utilization of geothermal resources as a ‘green’ energy source. However, minimal research has been conducted into geothermal resource utilization and depletion impacts on thermophile biodiversity. Thermophiles are organisms which have adapted over millions of year to extreme temperature and chemical compositions and exist in hot springs and other geothermal resources. Their ability to withstand high temperatures makes them invaluable to scientific and medical research. Current federal and California case law classify geothermal resources as a mineral, not a water resource. Acquisition of rights to develop a geothermal resource owned or reserved by the …