Sökning: "Paleozoikum"

Visar resultat 1 - 5 av 7 uppsatser innehållade ordet Paleozoikum.

1. 1. Geobiological Impacts of PalaeozoicLand Plant Evolution

   Master-uppsats, Uppsala universitet/Paleobiologi

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

   Sammanfattning : 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. LÄS MER

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

   Kandidat-uppsats, Stockholms universitet/Institutionen för geologiska vetenskaper

   Författare :Malvina Forbes Halldén; [2019]
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

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

   Master-uppsats, Lunds universitet/Geologiska institutionen

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

   Sammanfattning : 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. LÄS MER

5. 4. De mellankambriska oelandicuslagren på Öland : stratigrafi och faciestyper

   Kandidat-uppsats, Lunds universitet/Geologiska institutionen

   Författare :Johan Malmgren; [2016]
   Nyckelord :Öland; Sverige; kambrium; trilobiter; Acadoparadoxides oelandicus; Ellipsocephalus polytomus; Earth and Environmental Sciences;

   Sammanfattning : The thesis deals with a drill core retrieved from northern Öland, Sweden, in 2010. The length of the core is c. 107 m and comprises an Ordovician and Cambrian succession. The middle Cambrian primarily consists of fossiliferous mudstone with thin siltstone beds. LÄS MER

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

   Master-uppsats, Uppsala universitet/Institutionen för geovetenskaper

   Författare :Gauthier Hainaut; [2015]
   Nyckelord :Paleontology; Trilobite; Devonian; Biometry; Morphometry; Covariance;

   Sammanfattning : 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. LÄS MER