Hittade 3 avhandlingar innehållade ordet mid-Ordovician.
1. The flux of extraterrestrial spinels to Earth associated with He-3 anomalies in Cenozoic and Ordovician sedimentsDetta är en avhandling från Lund University
Sammanfattning : The main goal of this thesis is to reconstruct the flux of extraterrestrial matter to Earth in specific time intervals of our past in order to add an astronomical dimension to the understanding of Earth's history. To accomplish this, extraterrestrial chrome-spinel grains have been extracted and analysed. LÄS MER
2. The flux of extraterrestrial matter to Earth as recorded in Paleogene and Middle Ordovician marine sedimentsDetta är en avhandling från Lund University
Sammanfattning : This thesis aims at reconstructing events in the solar system, mainly collisional events in the asteroid belt, by searches for extraterrestrial minerals in Paleogene and Middle Ordovician marine sediments on Earth. Recent empirical evidence show that Earth has experienced a few brief periods during the Phanerozoic when the flux of extraterrestrial matter significantly increased. LÄS MER
- Detta är en avhandling från Lund University
Sammanfattning : This thesis deals with signatures in sediments on Earth related to the L-chondrite parent body break-up event at 470 Ma. The aim of this thesis is twofold: (1) investigate if the increased flux of extraterrestrial material to Earth, following the disruption of the L-chondrite parent body included larger, asteroid-sized bodies (2) try to develop new methods and tools for finding and classifying relict cosmic material in sediments. LÄS MER