Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 5 of 5
Full-Text Articles in Stratigraphy
Foraminiferal Faunas Of The Southern California Bight: A Temporal And Spatial Comparison Of Assemblages In The >150, 63-150, And >63 Μm Fractions, Amanda S. Shepard
Foraminiferal Faunas Of The Southern California Bight: A Temporal And Spatial Comparison Of Assemblages In The >150, 63-150, And >63 Μm Fractions, Amanda S. Shepard
All-Inclusive List of Electronic Theses and Dissertations
Analyses ofliving (Rose Bengal stained) deep-sea benthic foraminifera collected on the Southern California margin reveal temporal and spatial changes in foraminiferal assemblages related to changes in sea-surface productivity. Samples were collected from two sites in May, August, and October 1996. Results show that foraminiferal microhabitats are not static at these sites, and some species ( e.g., Bolivina spissa and Uvigerina peregrina) responded to the change in seasons with a change in their vertical distribution profiles, which is indicative of microhabitat preferences. Species such as Buliminella tenuata changed sediment depth in different stages of their life cycles, which has implications for …
From Sand To Sandstone: Documenting The Total Change During Diagenesis, Wilfrido Solano-Acosta
From Sand To Sandstone: Documenting The Total Change During Diagenesis, Wilfrido Solano-Acosta
All-Inclusive List of Electronic Theses and Dissertations
The objective of this study is to provide a more comprehensive picture of sandstone diagenesis from a different perspective; starting from an analog sand serving as a precursor of a lithified sandstone.
Chemical Weathering Of Volcanic Ash As A Probable Origin Of Chert In The Reid's Mistake Formation Of The Newcastle Coal Measures, Sydney Basin, Australia, Adil M. Wadia
All-Inclusive List of Electronic Theses and Dissertations
Chert is normally considered to be marine biogenic in origin. However, chert lenses and nodules in the volcanic ash horizon of the Reid's Mistake Formation at Swansea Head, Newcastle Coal Measures of the Sydney Basin appear to have formed differently. Their mode of occurrence and their close association with paper-thin clay layers within the same volcanic unit suggest that they formed as a result of chemical weathering of volcanic ash. This hypothesis is supported by the data gathered from thin section petrography and x-ray diffraction analyses. Petrographic studies indicate the precipitation of microcrystalline to cryptocrystalline quartz and the dissolution/replacement/alteration of …
Lithologic And Structural Controls On Karst Landforms Of The Mitchell Plain, Indiana, And Pennyroyal Plateau, Kentucky, Frederick Jennings Woodson
Lithologic And Structural Controls On Karst Landforms Of The Mitchell Plain, Indiana, And Pennyroyal Plateau, Kentucky, Frederick Jennings Woodson
All-Inclusive List of Electronic Theses and Dissertations
Karst features in Harrison County, Indiana, and the Mammoth Cave region, Kentucky, are profoundly influenced by lithology and structure. In the Sinkhole Plain two classes of sinkholes, shallow solutional and deeper subsidence, differ in morphology, origin, age, distribution, and density. Distributions of the two kinds of sinkholes reflect the outcrop pattern of specific lithostratigraphic units. Broad shallow dolines (Ste. Genevieve-type sinks) develop on the Horse Cave Member of the St. Louis Limestone and on the Ste. Genevieve, Girkin, and Paoli Limestones. Innumerable steeper-sided subsidence and collapse depressions (St. Louis-type sinkholes) form on the Corydon Chert Member, lower St. Louis Limestone, …
The Geology Of The Pittsburg Landing Area, Snake River Canyon, Oregon-Idaho, David L. White
The Geology Of The Pittsburg Landing Area, Snake River Canyon, Oregon-Idaho, David L. White
All-Inclusive List of Electronic Theses and Dissertations
The major purpose of the study was to map, describe, and correlate the pre-Tertiary rocks. Accessible and excellent exposures at Pittsburg Landing enabled the writer to make a somewhat detailed study of the stratigraphy. The thesis area also offered an opportunity to study in a reconnaissance manner, the Tertiary Columbia River Basalt as described by Waters, and more recently y Ozier.