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FORAMINIFERA AND ASSOCIATED ENVIRONMENTS OF BAHÍA INGLESA, NORTH-CENTRAL CHILE (27°S)Berger, Rachel Lynn 01 December 2010 (has links)
A total of 24 Neogene sediment samples were collected near Bahía Inglesa (27° 07' 40.78'' S, 70° 50' 41.47'' W and 27°07' 44.90'' S, 70° 50' 46.06'' W), north-central Chile during the summer of 2004. Neogene sediment has previously been recognized in this region by Godoy et al., (2003). Using standard laboratory techniques, samples were processed for both planktonic and benthic foraminifera. Statistical analyses were used on benthic foraminiferal data to infer paleodepositional environment and relative water depth. Planktonic foraminifera, when present, were used to establish a general age for samples; no planktonic foraminifera were found in sediments collected from the northern section sampled. Planktonic foraminifera found in the southern section indicate a Middle Miocene age (11.4 to 15 Ma). Statistical analyses of benthic foraminifera showed the presence of one foraminiferal assemblage for the northern section, Rocas Negras North (RCN) and produced two assemblages for the southern section, Rocas Negras South (RCS). RCN is interpreted to be a stable upper middle bathyal environment (< 1,000 m water depth) while RCS ranges in water depth from inner shelf (<50 m) to upper bathyal water depths (165-302 m). A difference in environments between localities is attributed to the location of sample sites relative to a NNE-SSW trending normal fault that separates them. Both localities shallow upwards, which is consistent with widely accepted ideas of a decrease in global temperatures and a general decline in eustatic sea level throughout the Neogene.
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Foraminifera from the Cretaceous of the Central Cordillera of Guatemala /Ashworth, Edwin Thomas January 1975 (has links)
No description available.
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Neogene planktonic foraminifera : studies on Indo-Pacific oceanic sections / by Robert S. HeathHeath, Robert Sturm January 1979 (has links)
185 leaves : ill., photos., charts, graphs, 11 fold. charts in end pocket ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Geology, 1981
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Neogene planktonic foraminifera : studies on Indo-Pacific oceanic sections / by Robert S. HeathHeath, Robert Sturm January 1979 (has links)
185 leaves : ill., photos., charts, graphs, 11 fold. charts in end pocket ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Geology, 1981
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Γεωλογική και στρωματογραφική μελέτη του Μεγανησίου, Ιόνια νησιάΚούσης, Ηλίας 11 October 2013 (has links)
Το Μεγανήσι και οι μικρότερες νησίδες Κυθρός και Θηλειά βρίσκονται στο
Εσωτερικό Αρχιπέλαγος του Ιονίου Πελάγους. Κατά το διάστημα Μέσης – Ανώτερης
Παλαιολιθικής (μπορεί και Κατώτερης) αποτέλεσε χώρο κατοίκισης προϊστορικών
ανθρώπων, προφανώς εξαιτίας της άφθονης παρουσίας της πρώτης ύλης για την
κατασκευή λίθινων εργαλείων (κερατόλιθος) αλλά και της ύπαρξης προνομιακών για
την επίβιωση σπηλαίων και άλλων καρστικών δομών. Το αντίστοιχο διάστημα στη
γεωλογική κλίμακα του χρόνου τοποθετείται μέσα στο Ανώτερο Πλειστόκαινο. Η
κύρια τεχνοτροπία των λίθινων τέχνεργων που έχουν βρεθεί είναι Μουστέρια και
αυτό αποδεικνύει ότι οι κάτοικοι ήταν Νεάτερνταλ (Homo neanderthalensis King,
1864). Αυτό το γεγονός προκάλεσε το ενδιαφέρον της επιστημονικής κοινότητας, με
αποτέλεσμα να ξεκινήσουν αρχαιολογικές και γεωλογικές έρευνες. Η εκπόνηση της
παρούσης εργασίας ελπίζουμε ότι θα καλύψει ένα μεγάλο μέρος των γεωλογικών
μυστηρίων που κρύβει πίσω του το Μεγανήσι. / The main topic of the project is the geological and stratigraphical analysis of Meganisi island.
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Quaternary history of the Polar Front in the Scotia Sea, Antarctica : foraminiferal and stable isotope evidenceHale, Ruth Elisabeth January 2001 (has links)
No description available.
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Environmental factors affecting planktonic foraminifera abundance and distribution in the Northeast Gulf of MexicoRavula, Sharath Reddy 29 August 2005 (has links)
The shell composition of planktonic foraminifera used in many paleoreconstructions assumes they are accurately representing conditions at the surface/mixed layer. However, planktonic foraminifera are known to inhabit a depth range that extends below the mixed layer. In the present study, foraminifera were collected at discrete depth intervals using a Multiple Opening and Closing Net Environmental Sensing System (MOCNESS) in either cyclonic or anticyclonic eddies that had contrasting environmental conditions. The foraminifera abundances and distributions were compared to the water depth, temperature, density, and chlorophyll profiles. Nine species were found consistently among all the tows and composed at least 96% of the species found, though a shift in the species abundances and depths occurred between eddies. Species occurred where physical factors were compatible with conditions and feeding opportunities they were adapted to. Three species pink and white Globigerinoides ruber and Globigerinoides sacculifer thrived best when a steep density gradient resulted in a shallower mixed-layer that restricted them under more intense light and allowed them to better exploit their algae symbionts. Globigerina bulloides was found outside its sub-polar habitat because the waters of the cyclones were cool enough (less than 26??C) at the same depths that sufficient chlorophyll was available. Two species Orbulina universa, and Globorotalia menardii were consistently absent in the mixed layer, but tracked deeper chlorophyll concentrations. Three other species were found inconsistently among the tows: Hastigerina pelagica, Globigerinella siphonifera, and Globigerinella calida. H. pelagica probably follows chlorophyll concentrations. G. siphonifera, and G. calida have a preference for deeper waters within the photic zone. The drastic doubling to tripling of the foraminifera abundances in cyclones biases downcore reconstructions of sea surface temperature towards cooler conditions. Also, the shift in species composition between the two eddies indicates that in environments where eddies, upwellings, or rings exist may bias the downcore composition of each species towards cooler conditions. G. sacculifer was found to live primarily in the mixed layer and at least 75% of its downcore individuals are expected to represent conditions there. Researchers should consider the described species distributions to better understand the water column conditions they are reconstructing.
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Environmental factors affecting planktonic foraminifera abundance and distribution in the Northeast Gulf of MexicoRavula, Sharath Reddy 29 August 2005 (has links)
The shell composition of planktonic foraminifera used in many paleoreconstructions assumes they are accurately representing conditions at the surface/mixed layer. However, planktonic foraminifera are known to inhabit a depth range that extends below the mixed layer. In the present study, foraminifera were collected at discrete depth intervals using a Multiple Opening and Closing Net Environmental Sensing System (MOCNESS) in either cyclonic or anticyclonic eddies that had contrasting environmental conditions. The foraminifera abundances and distributions were compared to the water depth, temperature, density, and chlorophyll profiles. Nine species were found consistently among all the tows and composed at least 96% of the species found, though a shift in the species abundances and depths occurred between eddies. Species occurred where physical factors were compatible with conditions and feeding opportunities they were adapted to. Three species pink and white Globigerinoides ruber and Globigerinoides sacculifer thrived best when a steep density gradient resulted in a shallower mixed-layer that restricted them under more intense light and allowed them to better exploit their algae symbionts. Globigerina bulloides was found outside its sub-polar habitat because the waters of the cyclones were cool enough (less than 26??C) at the same depths that sufficient chlorophyll was available. Two species Orbulina universa, and Globorotalia menardii were consistently absent in the mixed layer, but tracked deeper chlorophyll concentrations. Three other species were found inconsistently among the tows: Hastigerina pelagica, Globigerinella siphonifera, and Globigerinella calida. H. pelagica probably follows chlorophyll concentrations. G. siphonifera, and G. calida have a preference for deeper waters within the photic zone. The drastic doubling to tripling of the foraminifera abundances in cyclones biases downcore reconstructions of sea surface temperature towards cooler conditions. Also, the shift in species composition between the two eddies indicates that in environments where eddies, upwellings, or rings exist may bias the downcore composition of each species towards cooler conditions. G. sacculifer was found to live primarily in the mixed layer and at least 75% of its downcore individuals are expected to represent conditions there. Researchers should consider the described species distributions to better understand the water column conditions they are reconstructing.
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The Colorado group in the Cold Lake heavy oil area, East-Central Alberta : biostratigraphy, paleoenvironments and regional correlations /Tu, Qiang, January 1900 (has links)
Thesis (M. Sc.)--Carleton University, 2004. / Includes bibliographical references (p. 137-151). Also available in electronic format on the Internet.
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Palaeoenvironments of the Gulf of Carpentaria from the last glacial maximum to the present, as determined by foraminiferal assemblagesHolt, Sabine. January 2005 (has links)
Thesis (Ph.D.)--University of Wollongong, 2005. / Typescript. Includes bibliographical references: leaf 215-246.
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