Physical Sciences and Mathematics Commons^™

Discrimination Of Subparallel Beach Ridges Using Detrital Ilmenite Composition And Fourier Shape Analysis, Allen E. Evans Jr.

OES Theses and Dissertations

Elemental composition (Fe, Ti, Mn, Mg, V, Cu, Ni, Zn, and Cr) and Fourier shape analysis of magnetically separated detrital ilmenite from seven Pleistocene and modern beach sand deposits of the Southeastern Virginia Coastal Plain were used to distinguish each deposit. Geomorphic expression, crosscutting relationships and proximity to the present shoreline differentiates the relative age of the seven sampled beach deposits. Analysis of ilmenite elemental composition, independent of geomorphic expression, distinguished beach sands of

different age and was successful in determining that each beach contained ilmenite similar in composition. Of the seven beach ridges tested, subtle yet significant differences in …

Depositional And Diagenetic History Of The Middle Ordovician Carbonates Of The Shenandoah Valley, Northern Virginia, Lynn Ellen Weyenberg

OES Theses and Dissertations

An examination of the Middle Ordovician carbonates in northwest Virginia has revealed a particularly sensitive record of deposition and subsidence. Two-hundred acetate peels from six measured stratigraphic sections in Shenandoah County, Virginia were examined to interpret the depositional and diagenetic history. Two major lithofacies have been recognized within the New Market Limestone and three have been recognized in the Lincolnshire Formation. These five lithofacies represent an overall transgressive sequence. This transgression was not uniform but paused several times to allow carbonate deposition to reach sea-level. These shoaling events suggest a slowly subsiding basin in this region. The carbonate rocks within …