Physical Sciences and Mathematics Commons^™

Late Pleistocene Sciurids From Kokoweef Cave, H. Thomas Goodwin

Loma Linda University Electronic Theses, Dissertations & Projects

Three local (Tamias panamintinus, Ammospermophilus leucurus and Spermophilus variegatus) and five extralocal (Tamias minimus, Tamias palmeri, Marmota flaviventris, Spermophilus townsendii, and Spermophilus lateralis) sciurid species (Sciuridae) were identified from the late Pleistocene-early Holocene Kokoweef Cave paleofauna. This fauna was the first documentation of T. minimus, T. palmeri and S. townsendii from the Pleistocene of the Mohave Desert. The 30-ft sedimentary sequence apparently recorded the mid-to late-Wisconsian introduction of S. lateralis into the Kokweef fauna but otherwise documented general taxonomic stability. The ecological diversity of the fauna was consistent with--but did not require--the hypothesis of more equable late Pleistocene climates, and …

Geology And Petroleum Potential Of The Hay Creek Anticline, North-Central Oregon, Stephen I. Wareham

Loma Linda University Electronic Theses, Dissertations & Projects

For many years it has been reported that the core of the Hay Creek Anticline exposes metamorphic rocks of Paleozoic or Mesozoic age. On closer study it was found that these rocks consist of only slightly metamorphosed black to dark grey siltstones and sandstones with less abundant chert pebble conglomerate and recrystallized limestone. The sequence is here informally named "Hay Creek Formation." Calcareous nannofossils recovered and identified from the limestone yielded an age of early to middle Eocene.

The depositional environment of the "Hay Creek Formation" is interpreted to be a submarine turbidite fan. Siltstones were deposited as pelagic rain …

Factors Affecting Epithecal Growth Lines In Four Coral Species, With Paleontological Implications, Jean-Luc Liénard

Loma Linda University Electronic Theses, Dissertations & Projects

The number of epithecal (external) growth lines was surveyed over 124 days for Montastrea annularis growing at different depths (3.5 m to 61 m). There was a significant (P< .01) decrease in the number of lines with depth. Although the linear regression is significant, there is evidence for a logarithmic or quadratic relationship, and more data from greater depths are needed to determine which of these gives a better fit.

The number of growth lines formed during light-dark cycles of 16, 24 and 32 hours were compared for M. annularis, M. cavernosa, Porites astreoides and Tubastrea aurea. The variability among colonies from the same species was in many cases more significant than that among light treatments. This is a serious problem for anyone counting lines in corals, especially from a few specimens; therefore conclusions based on such counts seem hazardous on …

Paleocurrent Analysis Of The Cretaceous Mitchell Formation, North-Central Oregon, Craig A. Sandefur

Loma Linda University Electronic Theses, Dissertations & Projects

Cretaceous sedimentary rocks of north-central Oregon previously referred to as the Hudspeth and Gable Creek formations and recently renamed the Mitchell Formation are potential petroleum source and reservoir rocks. Thus, determining their extent under the cover of Tertiary volcanics is of great importance to future petroleum exploration in the southern half of the Columbia Basin. The direction of sediment transport has been previously studied by several workers with contradicting results and conclusions. The primary objective of this research was to expand the paleocurrent analysis using both macro- and micro-fabric to provide additional evidence of sediment transport direction. This information allows …