Physical Sciences and Mathematics Commons^™

Comparison Of Non-Heating Paleointensity Techniques Using Basalts From Lemptégy Volcano, France And Synthetic Magnetite-Bearing Samples, Geoffrey A. Lerner

Dissertations, Master's Theses and Master's Reports - Open

Data of the strength of Earth’s magnetic field (paleointensity) in the geological past are crucial for understanding the geodynamo. Conventional paleointensity determination methods require heating a sample to a high temperature in one or more steps. Consequently, many rocks are unsuitable for these methods due to a heating-induced experimental alteration. Alternative non-heating paleointensity methods are investigated to assess their effectiveness and reliability using both natural samples from Lemptégy Volcano, France, and synthetic samples. Paleointensity was measured from the natural and synthetic samples using the Pseudo-Thellier, ARM, REM, REMc, REM’, and Preisach methods.

For the natural samples, only the Pseudo-Thellier method …

Using Paleomagnetism To Unravel The Mysteries Of The Summit Creek Basalts, Glynis Bawden

Summer Research

The Summit Creek Basalts are a sequence of steeply dipping subaerial late Eocene basaltic flows located southeast of Washington’s Mount Rainier. Despite previous petrologic and paleomagnetic investigations, the origins of these basalts are poorly understood. It is uncertain whether they erupted in situ or were transported to their present location by tectonic processes. It is possible that these lavas were derived from the same magma source as a sequence of flows in the Crescent Formation on the Olympic Peninsula, as both erupted between 45 and 50 million years ago and have similar chemical compositions. A new paleomagnetic analysis of the …