{"id":2189,"date":"2016-02-21T12:14:53","date_gmt":"2016-02-21T17:14:53","guid":{"rendered":"http:\/\/rockheadsciences.com\/?p=2189"},"modified":"2016-02-27T07:40:57","modified_gmt":"2016-02-27T12:40:57","slug":"armistead-structural-geology","status":"publish","type":"post","link":"http:\/\/rockheadsciences.com\/armistead-structural-geology\/","title":{"rendered":"PhD Candidate, Gondwana Tectonics, Sheree Armistead @geoSheree: A Day in the GeoLife Series"},"content":{"rendered":"
Sheree Armistead at Mount Cook, New Zealand. \u00a92016 Sheree Armistead<\/p><\/div>\n
NAME:<\/b>\u00a0 Sheree Armistead<\/p>\n
CURRENT TITLE:<\/b>\u00a0 PhD Candidate, The University of Adelaide<\/a>, Australia<\/p>\n AREA OF EXPERTISE: \u00a0<\/strong>Tectonic evolution of Gondwana in Madagascar and India; structural geology and geochronology<\/p>\n YEARS OF EXPERIENCE:<\/strong> \u00a06 years experience (3 years undergrad, 1 year honors, 2 years geologist\/geochronologist for Geoscience Australia<\/a>, and currently undertaking PhD)<\/p>\n EDUCATION:<\/strong> \u00a0Currently a PhD candidate at the University of Adelaide, Australia<\/p>\n WEBSITE: \u00a0<\/b>\u00a0@geoSheree<\/a><\/p>\n What’s your job like?<\/b><\/p>\n My research is on how the supercontinent Gondwana formed around 850\u2013500 million years ago. A key piece of this puzzle is Madagascar, which was right in the middle of the major collision zone that formed Gondwana at that time. This ancient zone is comparable to the modern day Himalayan collision zone. My research looks at how parts of Madagascar formed and their relationship to areas in both Africa and India.<\/p>\n I use a range of techniques to figure out the geology at this time including geochronology and structural geology. Structural geology involves taking a lot of measurements in the field, such as \u2018strike and dip\u2019 of bedding and foliations, and then trying to figure out the deformation history and how this relates to larger tectonic processes.\u00a0For geochronology, I primarily use U-Pb dating of zircons. The tiny little zircon grains are super tough, so they record the age of when they crystallised in a magma \u2013 even if they have since been removed by weathering processes. The zircons might be in their original magmatic rock, or incorporated into later sedimentary rocks.<\/p>\n Operating the SHRIMP at Geoscience Australia; this machine is used to find out the ages of zircons. \u00a92016 Sheree Armistead<\/p><\/div>\n What’s a typical day like?<\/b><\/p>\n There\u2019s not really a typical day as a geologist. My work varies a lot between field work, lab work, analysing data and writing up results. I recently completed field work in India, so as an example, I\u2019ll run through a typical day of field work.<\/p>\n Firstly, the group will work out the plan for the day, identifying specific areas we want to go and look for rocks that will help us answer the big geological questions for my project. Often we don\u2019t know until we\u2019re right there as to whether there will be a good outcrop, so there\u2019s a lot of driving around looking for rocks! Indians love to drink tea, or as they call it \u2018chai\u2019. So there are lots of chai stops which we manage to find in even the most remote villages. Once we see some good outcropping rock, we stop. We record global position system (GPS) coordinates, take detailed notes about the rock types and then hammer off a sample. We stop at maybe five or so sites each day, depending on how far we need to drive. The evenings are usually quite relaxed; we briefly discuss the importance of the days\u2019 activities in the context of the larger research questions and enjoy some delicious Indian food and beer.<\/p>\n<\/a>