Showing posts with label Johan Erikson. Show all posts
Showing posts with label Johan Erikson. Show all posts

Wednesday, June 10, 2009

Patterns

In gravel pit after gravel pit, we’re seeing a similar pattern in sediments and depositional environments. Dr. Erikson has pointed out that almost every good exposure over about 10 m tall has a base of sand and cobble beds that gradually become finer grained upward in the section. This is typically overlain by more than a meter of bluish-grey marine clay, and then by the rapid return of sandy beds. As he explained, this is evidence of a history of dropping energy levels as sea level rose (yielding finer grain sizes), until only the finest particles (clay) accumulated in an offshore location, and then finally increasing energy levels as sea level fell (producing the return of sand above the clay). Occasionally, we’ve found large boulders dropped in the middle of the clay or sandy layers (as seen in the picture); the boulders are far too large to have been transported by ocean currents, so we can tell that glaciers were floating around in the ocean above the gravel pits dropping boulders and other debris as they melted.

We’ve made a number of observations this week and a half that have nothing to do with science. Our live animal sightings have extended to include another moose, a mouse, deer, groundhog, porcupine, blue herons, three fox kits, and dozens of alewives and herring in a fish lift. Other interesting sightings include two large windmill blades (allegedly 150-ft) pulled by semis. There has been a dramatic change in lifestyle in this upper region of Maine. We have found that people have been universally friendly and they have allowed us unrestrained access to their land, the traffic among the towns is nearly nonexistent, and everywhere we have eaten the portions have been plentiful. Our campground for the week located in Madison was much bigger than the last, but just as quiet. Our tent site includes an Adirondack structure which is a 3-walled shelter, which came in handy this week as we saw a drastic change from sunny and high temps, to rainy and low temps.

Thursday, May 21, 2009

Grant Award

Welcome to this new Mineral Sorting blog, a blog designed to document a faculty-student research project based at Saint Joseph's College!

Recently, I received word that my two-year $50,000 grant proposal to the American Chemical Society was accepted. This funding will allow me, and student researchers from the Department of Natural Sciences at Saint Joseph's College, to examine geologic processes affecting the mineral composition of early post-Ice Age sediments in Maine.

The research has implications for interpretation of long-term climate changes and their effects on the landscape. This is basic research on how the rock record preserves a history of events on the Earth’s surface.

The grant supports three weeks of field work during two summers to collect sediments, which will be brought back to the campus lab for mineral identification. Our research team also will figure out the size distribution of the collected sediments in order to shed light on how natural geological sorting processes affect the distribution of minerals in the rock.

I hope that you will consider following our progress.