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1	Stratigraphy and foraminifera of the upper part of the Nye formation, Yaquina Bay, Oregon Heacock, Robert Leon 15 November 1951 (has links) Graduation date: 1952 Foraminifera, Fossil Geology, Stratigraphic -- Oligocene Geology -- Oregon -- Lincoln County
2	Petrology of the reversely zoned Mickey Pass Tuff, west-central Nevada Templeton, Jeffrey H. 03 September 1998 (has links) Graduation date: 1999 Volcanic ash, tuff, etc -- Nevada Geology, Stratigraphic -- Oligocene Petrology -- Nevada
3	Stratigraphy and depositional history of the Pantano Formation (Oligocene-early Miocene), Pima County, Arizona Balcer, Richard Allen January 1984 (has links) No description available. Geology, Stratigraphic -- Miocene. Geology, Stratigraphic -- Oligocene.
4	Depositional systems and tectonic/eustatic history of the Oligocene Vicksburg episode of the northern Gulf Coast Coleman, Janet Marie Combes, 1952- 10 July 2013 (has links) Regional depositional systems analyses combining surface and subsurface geological and geophysical data provide the framework for a sequence stratigraphic study of the Lower Oligocene Vicksburg Formation of the Gulf Coastal Plain. The results describe the eustatic history of the Vicksburg stratigraphic unit. The two primary Texas depocenters, the Houston embayment and the Rio Grande embayment, were separated by a deep-rooted structural nose: the San Marcos arch. A barrier / strandplain intervened between the Louisiana deltaic depocenter and the Houston embayment. Within the embayments, deltaic complexes merged along strike with barrier / strandplains. Contemporaneous growth faulting controlled deltaic depositional patterns in the Rio Grande embayment and, to a lesser degree, in the Houston embayment. Smaller wave-dominated delta complexes interspersed with barrier / strandplains extended across the San Marcos arch. Updip of the paralic depocenters, fluvial systems traversed coastal plain units. Seaward of the paralic systems, sand and mud deposits prograded across and built up over the relict Jackson shelf and shelf margin. The contact between the Vicksburg Formation and the underlying Jackson Group marks the position of the Eocene - Oligocene boundary within the Gulf Coastal Plain section. On regional dip-oriented well-log cross sections there is a distinct, abrupt, seaward shift in the paralic facies at the Jackson - Vicksburg boundary; this contact corresponds to an Exxon-model Type 1 unconformity. The unconformity is related to the development of an Antarctic ice sheet in the earliest Oligocene. During middle Vicksburg time, a minor transgression (genetic stratigraphic sequence boundary) flooded the coastal plain. Overlying the progradational Vicksburg Formation, the lower Frio Formation accumulated in an aggradational mode; this switch of depositional modes corresponds to an Exxon-model Type 2 sequence boundary. Construction of genetic stratigraphic sequence diagrams and comparison to Exxon's coastal onlap curves across different areas of the Oligocene coast show that the effects of local depocenters (sediment influx) may mask eustatic effects. Only truly regional events, such as the middle Vicksburg transgression and the basal Vicksburg seaward shift in coastal position, correlate across the coastal plain and may result from a eustatic change. / text Geology, Structural--Gulf Coast (U.S.) Geology, Stratigraphic--Oligocene Sea level--Mexico, Gulf of Geology--Gulf Coast (U.S.)
5	Geology and geochemistry of hydrothermal alteration, eastern portion of the North Santiam mining area Pollock, J. Michael 01 January 1985 (has links) The Ruth Mine is a base-metal vein deposit near the eastern margin of a reported porphyry copper deposit in the Western Cascade Range in Oregon. Uplift of the Western Cascade Range has resulted in a deeply dissected terrain in which more than a kilometer of the stratigraphy overlying the porphyry-style mineralization is preserved and exposed. The stratigraphic units, which are middle Tertiary in age, have been given arbitrary letter designations beginning with the lowest unit (Unit A) through the uppermost unit (Unit D). Geology Stratigraphic -- Oligocene Geochemistry Geology
6	Stratigraphy and Depositional History of the Pantano Formation (Oligocene-Early Miocene), Pima County, Arizona Balcer, Richard Allen January 1984 (has links) The Pantano Formation comprises 1,250 m of alluvial, fluvial, lacustrine, and volcanic rocks deposited in a basin formed in response to regional extension during mid- Tertiary time in southeastern Arizona. During deposition, the locations and composition of sediment source areas varied as contemporaneous uplift occurred adjacent to the basin. The lower half of the formation was deposited as alluvial fans that prograded northward, westward, and southward; the upper half was deposited during southwestward retreat of alluvial fan deposition and the onset of lacustrine deposition. An andesite flow separates the two depositional regimes. Radiometric dates of 24.4 ± 2.6 m.y. B.P. for the andesite and 36.7 ± 1.1 m.y. B.P. for a rhyolitic tuff disconformably underlying the formation indicate that deposition occurred during Oligocene to early Miocene time. Proper stratigraphic sequencing and description, paleocurrent analysis, and gravel provenance study aided in understanding the depositional history of the formation. absolute age alluvial fans andesites Arizona Basin and Range Province basins Cenozoic dates environment geochronology igneous rocks interpretation lacustrine environment Miocene Neogene North America Paleogene Pantano Formation Pima County Arizona provenance rhyolites sedimentary basins sedimentary rocks sedimentation southern Arizona terrestrial environment Tertiary United States volcanic rocks Geology, Stratigraphic -- Miocene Geology, Stratigraphic -- Oligocene

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