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By Jay, on May 3rd, 2012% 
The Raleigh, North Carolina area is a peneplain. The area has been devoid of any mountain building events for quite some time so the land surface has very low relief. As a result, outcrops of exposed metamorphic bedrock across the Piedmont physiographic province are few and far between. Additionally, bedrock may be covered by a literal veneer of dense soil and/or saprolite which conceals the bedrock below by mere inches.
But fear not! I am a trained geologist and have become adept at finding these obscure bedrock outcrops. So for reference, and in case anyone wants to go and visit, lets start with a map that I cobbed together.
Site Location of Bedrock Outcrop along US-401 South, Raleigh, North Carolina – photo by J. Sents, 2012
I used the Wake County iMAPS GIS [Beta] for the base layers used to create the map above. The location presents itself as an unpaved, unmarked parking lot. Along the southern edge of the lot, a stand of trees and bushes conceals the exposed bedrock. So a few days after the initial identification of this site, I made first contact with my camera and compass.
Bedrock Outcrop Photograph facing South – photo . . . → Read More: Raleigh Bedrock Outcrop
By Jay, on August 23rd, 2011% 
Imbrication is one of those geologic phenomenon that occur and are recorded at a scale that we can readily see. What is it? Imbrication is the orderly, overlapping arrangement of flattened or sub-spheroidal grains in the direction of flow. Flow in this case is usually water flow, but it can be other types of fluid flow [ice, wind, and even metamorphism]. Grains are commonly sand- to gravel-sized particles. However, with other types of fluid flow or metamorphism, these can often be large-scale or even microscopic.
For the purposes of this discussion, we’re going to focus on water flow and gravel-sized particles. Below is a diagram from the University of Montana Geology Department [2011] depicting varying degrees of imbrication:
Three varying degrees of pebble imbrication with respect to flow direction. (UMT, 2011)
On a recent trip to Wrightsville Beach in Wilmington, North Carolina, I came across this shell bed. Can you see the imbrication in the photograph? I put my sunglasses in for scale, and some background into the scene so you could see the orientation of the beach with respect to the Atlantic Ocean:
Clast-supported imbrication of a shell bed on a beach. (photo by J. Sents – . . . → Read More: Imbrication
By Jay, on June 19th, 2010% I’ve processed some photographs from a recent trip to the Raleigh Museum of Natural Sciences on June 4th, 2010. I’ll just string this into a long post of photos and comment on them as I go along.
In these photographs, the legend plate is located underneath each display. Each photo will open to a higher resolution version in a new window. I didn’t rotate these guys, or dress them up all nice ‘n pretty like, so please go easy on me!
Mineralogy is a fascinating sub-discipline of geology. It is technically rigorous with it’s chemistry, yet it still possesses the mystique of medieval alchemy. Identifying minerals using field tests can be a challenging exercise fraught with easy pitfalls. For example, one should avoid using mineral color as the sole identifier. Once long ago, I was handed a sample of halite to identify during a laboratory mineralogy exam. It was a cubic sample [about 4 inches per side] with well-worn faces, edges and corners, and it contained a cloudy azure blue inclusion. Everyone thought I was stumped until I gave this sample a big old lick with my tongue. They were flat-out astonished as I gently placed the sample back into . . . → Read More: North Carolina Minerals
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