Hungry for some Geology?!In the Thermochronology Analysis for Structure and Tectonics laboratory (TASTe lab), at CSULB, we focus on regional tectonics questions--reconstructing structural relationships and documenting surface processes in space and time using low-temperature thermochronometry, geochronology, and geochemistry.
What is Thermochronology?Thermochronology is a method used to date the cooling age of a rock. You may be familiar with geochronology used to date the formation age of rocks. Thermochronology is similar but instead of dating when the rock formed we are dating when a rock was cooled (or reheated and cooled) after it had already formed. To do this we measure the amount of elements in a mineral that undergo natural radioactive decay. When these elements decay they produce different products (for example atoms like He or crystal damage like fission tracks), which accumulate in a crystal over time. So, after a long time a mineral might have a lot of extra helium or fission tracks. However, these decay products are temperature sensitive! This means that if the temperature is relatively high those decay products might disappear (for example the He can diffuse out of the crystal or the fission tracks can heal themselves). Different minerals are sensitive to different temperatures, so by analyzing different systems we can obtain information about when rocks cooled below certain temperatures and how long it took to cool from one temperature range to another!
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Sometimes when you've been out in the field too long rocks start to look like food
Photo credit Dr. Devon Orme: Tibet. Rock very reminiscent of a slice of white bread.... |
What can effect the temperature of a rocks?
Rocks can cool by getting closer to the surface of the Earth driven by
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Facilities & Equipment(1) The "dusty lab" for crushing rocks
(2) The "separation lab" for separating different minerals with sieves, water, heavy liquids, and big ol' magnets (i.e. Frantz) (3) The "picking lab" which sports a Leica Stereo Microscope (M165) and attached camera system for selecting minerals for Thermo- & Geo-chronology. (4) The "M&M lab" for mapping and modeling work, we have computers with high expanded memory capacity and quality graphics cards. |
Alyssa Abbey
Ph.D., 2018 Earth and Environmental Sciences | University of Michigan B.S., 2012 Geosciences | University of Arizona B.A., 2012 French | University of Arizona Hometown: Tucson, AZ Research Interests: Thermochronology, Tectonics, fault growth processes, continental rifting, Geoscience education Other Interests: Hiking and camping, bike-packing, musical theater, reading, gardening |