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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 March 29th, 2012% It was hiding in plain sight. Let me get through some other issues and then I’ll post some pics, the location, and the structural information…
By Jay, on August 23rd, 2011% I felt that one. I’ll give it a III-IV on the Modified Mercalli Intensity Scale. My refrigerator would concur. Here are the preliminary technical details from the United States Geological Survey. Sheesh. Hurricanes. Earthquakes. The End is Nigh!
More to follow…
By Jay, on March 20th, 2011% I didn’t really see anything extraordinary about it. Should I write home? I suppose after all, it was a nice North Carolina evening after a great couple of days of super warm weather!
The Boylan Street Bridge was a zoo with people and cameras, so I decided to go to a spot a little off the beaten path. This isn’t a spectacular photograph but I put the Archdale Building in there for reference. That’s where many of the NC Geologic and Soil Survey folks live Monday through Friday. Enjoy.
It required a little post-processing work but the green lights against the Archdale Building look cool with the orange.
By Jay, on February 9th, 2011% 
Looking around town ahead of some warmer weather and outdoor activities, I checked out the Wake County GIS Internet Multi Access Parcel System. A mouthful for sure. We can just call it IMAPs, or interactive maps to keep things simple here. This system is so cool for looking up places to check out geology, do some forward recon for photography, or just snooping around in general. What is it?
IMAPs is a Geographic Information Systems [GIS] interactive, web-based tool published by Wake County and Raleigh, North Carolina. I believe there may be some coordination between the municipal end and North Carolina State University and UNC Chapel Hill. What is GIS?
GIS is an approach to mapping electronic data stored in a database. It’s extremely useful because of the way things are mapped. Data are queried in a transparent fashion behind the scenes from a relational database, and then filtered, organized, and managed on individual sets of digital drawings. These drawings are referred to as layers. Think of each layer as a sheet of clear paper with one type of data drawn on it: roads for example. Another layer may have rivers. And another layer may contain land use information [wilderness, . . . → Read More: Interactive Online GIS Tool
By Jay, on October 12th, 2010% 
So much to read and so little time. In addition, looking much more closely inside the Raleigh Beltline for some geology-related places is heating up. I want to talk a lot more about this photograph soon.
0208732534
Some call it 0208732534. I call it the United States Geological Survey’s [USGS] stream gauge on Pigeon House Creek at Cameron Village. They are calling for rain here later in the week, so I would like to go back up here and take a few photographs during high flow stream conditions. Until then…
By Jay, on September 3rd, 2010% To be honest, I was sort of hoping for more of an impact this far inland from Hurricane Earl. Maybe not as bad as Fran or Hugo, but something. The folks that live out on the Outer Banks probably took some damage but they’re used to and can handle quite a bit way out there.
Oh well. The 2010 Atlantic Hurricane Season still has quite a bit of life. I really wanted to get some swollen streams around here to examine something with you. We have this type of regolith, or highly weathered bedrock, that rests right above the actual bedrock surface in the Piedmont of North Carolina. Sometimes referred to as Partially Weathered Rock, or more commonly Saprolite, I wanted to evaluate if this material shows evidence of weathering and erosion, or if it tends to weather in place, in the stream banks anyhow.
I’ll need some water chugging down these streams for that. Unfortunately, the only times this summer we’ve had the types of heavy rainfall required have been very late at night. Fret not. There’s plenty of Hurricane Season left. Hopefully, we get some good rain on a day I can run over to a stream near . . . → Read More: So No Hurricane Earl
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
By Jay, on June 2nd, 2010% So let it begin. Let me tell you something about central North Carolina. Outcrops are as scarce as hens teeth. But you can find them. You can find them if you look hard enough, and sometimes, when not looking at all. They certainly like to hide in plain sight.
Figure 1. Facing west along Crabtree Creek toward Old Lassiter Mill Dam – photo by J. Sents
Not to worry though. I am a trained geologist, so I’ll lead you through it all painlessly. Let’s start with Lassiter Mill Dam. Now, I’m probably going to make this a series of posts that start from the “Big Picture”, and then we can zoom into the all gory details. I figure since this forum is all about having some fun while learning something, it would just be easier on the eyes and brain. Let’s get it going.
The site of the Old Lassiter Mill is located about 3.5 miles north of downtown Raleigh, North Carolina as a crow flies. All that remains of the old grist and saw mill complex is a dam and mill race—a structure used to redirect and concentrate water flow toward a water wheel. The dam is built . . . → Read More: Nutbush Creek Fault near Lassiter Mill Dam
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