Fieldwork in the Neoproterozoic
Professor Phoebe Cohen of the Geology Department at Williams College will speak at Science Workshop on Friday, 5 April, at 1:00 pm in Dickinson 225.
Her work combines microscopic and microchemical techniques with field-based stratigraphy and sedimentology to reconstruct ancient organisms and ecosystems. She will discuss her research in the context of our current knowledge about the evolution of life during the Neoproterozoic time period — the ~500 million years of Earth history before the rise of animals. While the sudden appearance of animals in the fossil record is dramatically demonstrated in the Cambrian radiation, the groundwork for animal evolution, and the co-occurring changes in marine ecosystems and ocean chemistry, were laid during the Neoproterozoic. Studies of the dynamic earth-life system in deep time present special challenges, but are transforming how we think about biology and geology.
Here are links for a) a paper for background on evolution in the Neoproterozoic, and b) a paper presenting some of Dr. Cohen’s research.
Students interested in having lunch with Dr. Cohen before her talk should be in touch with Kerry Woods.
Please plan ahead for a special Science Workshop with Professor Peter Ryan of Middlebury College on Friday, November 16 at 1:00. The title and abstract of the talk are presented below.
Arsenic in Vermont’s Groundwater Resource and the Connection between Geology and Public Health
Arsenic is a naturally occurring trace element in the natural environment, and in some regions geological factors have conspired to create elevated arsenic concentrations in the rocks and sediments that host groundwater. Research over the past ten years by the Vermont Geological Survey, the Vermont Department of Health and Middlebury College has revealed that certain parts of the state are prone to elevated arsenic in bedrock aquifers – these include parts of the Taconic slate region, the Rowe-Hawley Belt in north-central Vermont and parts of Windsor County in the vicinity of a granitic intrusion. This talk will explore geological, topographic and hydrological controls on groundwater arsenic in the complex geological landscape of Vermont and also reflect on recent changes to public policy as a result of scientific research.
Did you know that there are caves in the hills around Bennington?
Tim Schroeder‘s The Geology of the Bennington Region class explored one such cave on the north side of Mount Anthony on a recent class field trip. The caves are present in the Ordovician marble deposits that have been quarried in this region for centuries. The rocks were originally deposited as limestone in a reef-like setting when Bennington was on the margin of North America 500 million years ago. The rocks were metamorphosed to become marble during the tectonic events that built the Appalachian Mountains. The caves form now because the mineral calcite, which composes the marble, is slightly soluble in acidic rain water, and it slowly dissolves openings as the rainwater infiltrates into fractures in the marble. This particular cave is located very near one of the major faults that formed the Taconic range, which we also mapped on this field trip.
Students gather at the entrance to the cave they will explore at Mount Anthony, Bennington, VT.