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Full-Text Articles in Paleontology
Model Of A Biotic Hard Substrate Community: Paleoecology Of Large Trepostome Bryozoans From The Upper Ordovician (Katian) Of The Cincinnati Region, Usa, Kate Runciman
Senior Independent Study Theses
The calcite skeletons of trepostome bryozoan colonies from the Upper Ordovician (Katian) of the Cincinnati region record the diverse interactions and growth responses these colonies experienced. Trepostome specimens from three Cincinnatian strata; the Bellevue Member, the Bull Fork Formation, and the Whitewater Formation, were studied within this project. These three strata were deposited in a shallow epicontinental sea environment that was located in the southern subtropics, approximately 20-23°S at the time of deposition. The focus of this project was the paleoecology of large trepostome bryozoans, which was studied by examining bryozoan growth patterns, trace fossils, and sedimentation. Microscopic examination of …
Unearthing The Effects Of European-American Settlement On A Northeast Ohio Kettle Lake Through Diatom Stratigraphy, Justine Paul A. Berina
Unearthing The Effects Of European-American Settlement On A Northeast Ohio Kettle Lake Through Diatom Stratigraphy, Justine Paul A. Berina
Senior Independent Study Theses
Recently, wetland conservation has highlighted the necessity for assessing limnological changes following European-American settlement. A prior study at Brown's Lake (northeast Ohio) identified a stratigraphic sequence that shows an abrupt transition from organic-rich muds to several centimeters of a bright loess layer, then a recovery to organic-rich sediments near the top. Based on 210Pb dates, the loess deposition occurred before 1846 CE, when a growing population cleared trees and farmed intensively. Likewise, organics had recovered after 1950 CE, when people abandoned farmland and practiced conservation tillage. However, the effects of settlement on limnology are poorly known. Diatoms (microscopic algae; …
Paleoecology Of Bivalves In The Carmel Formation (Middle Jurassic, Bajocian) Of Utah, Evan L. Shadbolt
Paleoecology Of Bivalves In The Carmel Formation (Middle Jurassic, Bajocian) Of Utah, Evan L. Shadbolt
Senior Independent Study Theses
The Carmel Formation of the Middle Jurassic has many mysteries. One of these enigmas is its bivalves. The formation contains the famous oyster balls called ostreoliths. Despite bivalves making up 80 percent of the fossils found in the Carmel Formation, it is not understood how the bivalves lived in this community. The formation is located in southwestern and central Utah. It was deposited when an epicontinental seaway covered most of Utah. The paleoclimate of Utah was hot and dry, which meant that the environment was evaporite heavy. This also meant that the seawater at the southernmost extent of the seaway …
Paleoenvironments Containing Coryphodon In The Fort Union And Willwood Formations Spanning The Paleocene-Eocene Thermal Maximum (Petm), Bighorn Basin, Wyoming, Emily N. Randall
Paleoenvironments Containing Coryphodon In The Fort Union And Willwood Formations Spanning The Paleocene-Eocene Thermal Maximum (Petm), Bighorn Basin, Wyoming, Emily N. Randall
Senior Independent Study Theses
Preliminary data point toward a new hypothesis in which Coryphodon lived in wetter habitats before the Paleocene-Eocene Thermal Maximum (PETM), but was able to adapt to drier habitats in order to survive post-PETM. Early Paleogene nonmarine strata are extensively exposed in the Bighorn Basin of northwestern Wyoming. The Fort Union and Willwood Formations represent alluvial deposition within a Laramide Basin formed from the Paleocene through early Eocene. Therefore, the basin is an ideal place to study the local effects of the PETM, a rapid global warming event that occurred about 55.5 million years ago at the Paleocene–Eocene boundary. During this …
Encrusting Sclerobiont Paleoecology And Bioerosion Of Oysters In The Type Campanian (Upper Cretaceous) Of Southwestern France, Macy A. Conrad
Encrusting Sclerobiont Paleoecology And Bioerosion Of Oysters In The Type Campanian (Upper Cretaceous) Of Southwestern France, Macy A. Conrad
Senior Independent Study Theses
The Campanian Stage of the Upper Cretaceous was established by Henri Coquand in 1857 based on a sequence of richly fossiliferous shallow water carbonates in the Charente and Charente-Maritime departments of southwestern France. One of the most common macrofossils is the gryphaeid oyster Pycnodonte vesicularis (Lamarck, 1806), which often forms extensive shell beds. This bivalve lived primarily on soft marly substrates, forming hard substrate islands. They frequently supported sclerobiont communities comprising encrusters (diverse cheilostome and cyclostome bryozoans, foraminiferans, oysters, bivalves, sabellid and serpulid polychaetes, calcareous sponges), borers (the sponge borings Entobia, the worm borings Maeandropolydora and Caulostrepsis, the barnacle borings …
Tree-Ring Evidence Of North Pacific Volcanically Forced Cooling And Forcing Of The Pacific Decadal Oscillation (Pdo), Lauren Vargo
Tree-Ring Evidence Of North Pacific Volcanically Forced Cooling And Forcing Of The Pacific Decadal Oscillation (Pdo), Lauren Vargo
Senior Independent Study Theses
Two large undocumented volcanic eruptions in 1698/9 and 1809 have been previously identified in ice cores as sulfate peaks, and in tree-ring latewood density data as low-density rings. These eruptions can also be recognized using tree-ring width data, and can be identified in the tree-ring record as narrow rings for several consecutive years. The first part of this study uses tree-ring width data from the Gulf of Alaska to provide further evidence that these eruptions occurred. The two eruptions also provide a natural experiment for investigating the effects large volcanic eruptions have on North Pacific climate, including the Pacific Decadal …