You are browsing the archive for September 2016 - Page 2 of 2 - Mountain Beltway.
14 September 2016
Pillows in Icelandic basalts
Time is short these days, but I know you hanker for amazing geology. How about some pillow basalts from the Snæfellsnes* Peninsula, far western Iceland? Note the cm-demarcated pencil for scale. See if you can find it in the GigaPan version below: Link Handheld GigaPan by Callan Bentley, stitched with Microsoft ICE _________________________ * “Snay full snooze”
10 September 2016
Peat slide!
Not only does it turn out that peat grows on hill tops, not just valley bottoms, but it can slough off and create “peat slides” too!
9 September 2016
Friday folds: A study in contrasts at the Walls Boundary Fault, Shetland
A virtual field trip to the Walls Boundary Fault in Shetland reveals an embarrassment of Friday fold riches.
8 September 2016
Tension gashes in Malmesbury metasediments near Sea Point Contact
A small structural geology treat – several en echelon arrays of tension gashes (quartz-filled veins) in Malmesbury Group metasediments, Sea Point, South Africa.
4 September 2016
Lab Girl, by Hope Jahren
Lab Girl, by Hope Jahren, is a unique memoir. It describes Jahren’s journey through life from her childhood in the frigid northern Midwest to her eventual success as a celebrated scientist and an original thinker. The first thing you should know about it is that it is exceptionally well written (Hope Jahren Sure Can Write, after all) – evocative with joy and pathos and well articulated anxiety and the deep, …
3 September 2016
Viewing the Sea Point migmatite through the lens of GigaPan
It was five years ago when I first visited Sea Point, the outcrop on the coast of the Cape Peninsula where the Cape Granite (~540 Ma) intrudes the (meta-)sedimentary rocks of the Malmesbury Group. The outcrop is (a) beautiful and evocative, and (b) of historical importance, as Charles Darwin visited it while on the voyage of the Beagle, contemplating and confirming Lyell’s assertions of the validity of plutonism as he …
2 September 2016
Friday fold: isoclinal fold in ferruginous pelite and chert of the Fig Tree Group
A quick Friday fold – Ulundi Formation, basal Fig Tree Group of the Barberton Greenstone Belt, exposed in a creekbed etched into the trace of the Sheba Fault. This is one of the outcrops I visited one week ago today as part of the pre-IGC field trip to the Barberton. The rocks are iron-rich cherts and pelites that have enjoyed some serious strain, presumably due to movement along the Sheba …
1 September 2016
Archean microbial mats in the news and in GigaPan
The news yesterday of 3.7 Ga stromatolites in Greenland prompts a closer look at 3.22 Ga microbially-induced sedimentary structures in the Barberton Greenstone Belt’s Moodies group sandstones.
Callan Bentley is Associate Professor of Geology at Piedmont Virginia Community College in Charlottesville, Virginia. He is a Fellow of the Geological Society of America. For his work on this blog, the National Association of Geoscience Teachers recognized him with the James Shea Award. He has also won the Outstanding Faculty Award from the State Council on Higher Education in Virginia, and the Biggs Award for Excellence in Geoscience Teaching from the Geoscience Education Division of the Geological Society of America. In previous years, Callan served as a contributing editor at EARTH magazine, President of the Geological Society of Washington and President the Geo2YC division of NAGT.