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Found 5 essays matching the above criteria.

1. 1. Geobiological Impacts of PalaeozoicLand Plant Evolution

   University essay from Uppsala universitet/Paleobiologi

   Author : Camille Valette; [2021]
   Keywords : land plants; geobiological impacts; extinction; Palaeozoic; paleobotany; landväxter; geobiologiska effekter; utrotning; Paleozoikum; paleobotanik;

   Abstract : For two centuries, questions about the origin of terrestrial plants and their impacts on the Earth systemhave occupied palaeobotanists. This essay attempts to synthesise the state of research to date, and outlineareas where major questions remain. READ MORE

3. 2. Cr-spinels in the Franklinian Mobile Belt : a geochemical record of Paleozoic tectonics

   University essay from Stockholms universitet/Institutionen för geologiska vetenskaper

   Author : Malvina Forbes Halldén; [2019]
   Keywords : geology; geochemistry; spinel; Cr-spinel; chromite; SEM; scanning electron microscope; electron microprobe; EMP; electron probe microanalyzer; EPMA; electron micro probe analyzer; EMPA; petrogenetic indicator; microscopy; alteration; Franklinian Mobile Belt; Kulutingwak Formation; Clements Markham fold belt; Pearya; Paleozoic; suprasubduction zone; SSZ; island arc; IA; Arctic Canadian Archipelago; Ellesmere Island; Canada; 2017 Circum-Arctic Structural Events Expedition 19; Memorial University of Newfoundland; geologi; geokemi; spinell; Cr-spinell; kromit; SEM; svepeletronmikroskopi; elektronmikrosondanalys; EMP; EPMA; EMPA; petrogenetisk indikator; mikroskopi; Franklinian Mobile Belt; Kulutingwak-formationen; Clements Markham fold belt; Pearya; Paleozoikum; suprasubduktionszon; SSZ; öbåge; IA; Kanadas arktiska öar; Ellesmereön; Kanada; 2017 Circum-Arctic Structural Events Expedition 19; Memorial University of Newfoundland;

   Abstract : The chemical compositions of Cr-spinel extracted from mafic and ultramafic rocks collected on Ellesmere Island in the Arctic Canadian Archipelago were obtained through electron microprobe analyses. The extensively altered rocks are sampled from rock units in the Franklinian MobileBelt, which is representative of a Paleozoic tectonically active oceanic regime of which little is presently known. READ MORE

4. 3. A geophysical survey (TEM; ERT) of the Punata alluvial fan, Bolivia

   University essay from Lunds universitet/Geologiska institutionen

   Author : Joakim Mårdh; [2017]
   Keywords : electromagnetic; geophysics; TEM; Punata; alluvial fan; Earth and Environmental Sciences;

   Abstract : The Punata alluvial fan, situated in central Bolivia (Valle Alto) between the Altiplano and the lowlands, is an important aquifer for the local rural population. Due to rapid development and population growth in the area, the demand for fresh water has increased in recent year. READ MORE

5. 4. Study of the Taxonomy and the Inter and Intra Specific Variability of Phacopidae from the Lower Devonian of Algeria: Morphometric Approach and Meaning.

   University essay from Uppsala universitet/Institutionen för geovetenskaper

   Author : Gauthier Hainaut; [2015]
   Keywords : Paleontology; Trilobite; Devonian; Biometry; Morphometry; Covariance;

   Abstract : An Algerian Phacopid fauna, described by Lemaître in 1952, is reexamined here. Species arereevaluated in order to be in agreement with modern taxonomy. To characterize the size and shape of our specimens, as well as inter- and intraspecific variations, a morphometric analysis was performed. Only holaspids were analyzed. READ MORE

6. 5. Linguliform Brachiopods from the terminal Cambrain to lower Ordovician Tiñu section, Mexico

   University essay from Uppsala universitet/Paleobiologi; Uppsala universitet/Universitetsbiblioteket

   Author : Barbro Bornsäter; [2008]
   Keywords : Linguliform; Brachiopods; Acrotretid; Siphonotretid; Tiñu Formation; Cambrian; Ordovician; Linguliforma; Brachiopoder; Acrotretida; Siphonotretida; Tiñu formationen; Kambrium; Ordovicium;

   Abstract : Tiñuformationen i Oaxaca, Mexiko är den enda fossilförande enheten från undre paleozoikum mellan den Laurentiska plattformen i nordvästra Mexiko och de Gondwanska lagerföljderna i Sydamerika. Det har nyligen visats att Tiñusektionen är en koncentrerad passiv kantlagerföljd med Gondwanakaraktär. READ MORE