My former Honors student Laura graduated from NOVA a year ago and transferred to the University of Virginia. But during her second semester at UVA, she joined the SEA Semester program, and sailed around the world.

During Honors presentations this year, current Honors student Kristen (and friend of Laura's) brought in a gift from Laura: a collection of rocks and photos from Namibia, one of their ports of call on the trip.

With Laura's permission, I'm sharing some of the photos here today.

The scene in the Namib Desert:




Note the black stripe on the crest of the hill in this shot:


It appears to be a dike of basalt/dolerite/mafic rock:



Boulders of the mafic rock go tumbling down a ravine:


The SEA Semester group's campsite:




Laura pulls a folded & boudinaged granite dike out of her hat:


Closer shot of the geology:






The rock cross-cut by the granite dike. Namibian dollar for scale; same size as American quarter:




Little tafoni hole:


Bigger tafoni holes:


Medium-sized collection of tafoni holes:


While I'm sharing other people's Namibia photos, go check out the collection from Greg Willis, a blog reader who attended the GSW spring field trip on Sunday.

Thanks, Laura, for the rocks and for the photos!

Labels: africa, geology, granite, namibia, nova

Following on yesterday's Namibiferific post, I'd also like to share this image:

Labels: africa, meteors, namibia, travel

Today's NASA Earth Observatory image of the day is of a place that is near and dear to my heart, the Etosha Pan of Namibia:



In late 1996, my father and I took a trip to Namibia to study termite mound gas exchange as part of an Earthwatch expedition, and afterwards we rented a car and went off on a little safari. Up in Etosha National Park, the wildlife was pretty amazing. Here's a leopard that crossed the road in front of us, immediately followed by a second leopard:



An oryx (or gemsbok):


...And an elephant, drinking from one of the watering holes that fringe the main salt flats:


Namibia has been getting a lot of water lately, as evidenced in compare/contrast images like these, also from NASA's Earth Observatory:

June 2007:


Last week:


And that brings us back to the first image:


In this picture, you can see a new package of river water coming south into the Etosha Pan from the Oshigambo River of Angola. This is "fresh" water, but it has a dissolved load of sediments in it. As the water hits the hot, baking expanse of the Etosha Pan, it evaporates, but the dissolved ions within don't have that option. So they become more and more concentrated, and settle out in a chemical precipitate. This is where all the salt comes from: even freshwater is a little bit salty, and when you evaporate it repeatedly in an enclosed drainage basin, evaporite minerals accumulate there.

Labels: africa, critters, floods, mammals, namibia, national parks, salt, travel

That is the Richat Structure in Mauritania. It's wild looking. Dave has posted on it previously, so I won't add to his ample discussion here, except to say, "Whoa. That is seriously cool."

Labels: africa, deserts, structure

Ann Hornaday authored an interesting piece in this morning's Washington Post about Ota Benga, the Congolese Pygmy who was displayed for a time in a cage in the Bronx Zoo. It turns out that Ms. Hornaday's great-great-great-uncle, William Temple Hornday, was the one who put Ota Benga there.

Labels: africa, anthropology, new york, science and society

A special request from my fellow GSW member Nora Noffke (Old Dominion University), about a site in South Africa that Chris Rowan blogged about in May of this year:

The scenic Wit Mfolozi River Gorge in South Africa displays unique and spectacularly preserved sedimentary structures caused by microbial mats that colonized a sandy coastal area that are 3 billion years old. A comparison with modern microbial mats in a similar setting today suggests that the mat-constructing microbiota may have been cyanobacteria, possibly the oldest known in Earth history (GSA Today, October 2008).

In collaboration with the Society for Sedimentary Geology (SEPM), the Geological Society of America (GSA) and as part of the Year of the Planet Earth (IYPE), the Geological Society of South Africa (GSSA) is establishing the "Wit Mfolozi River Area" as a Geoheritage Site. This Geoheritage Site will serve visiting scientists, students and the interested public in leaning more about the Archean world and Earth's earliest life.

With the support of funds raised around the world, GSSA will set up the logistical and administrative infrastructure necessary to preserve and make this site available to all. This includes, for example, the construction of secure access to the site, installment of signs explaining the details of biogenic sedimentary structures at different spots in the outcrop and also measures to protect the site from damaging flooding by the river.

For further information about the site contact Roger Price (Geosite Conservation Committee, GSSA - rprice@geoscience.org.za), Nora Nofke (Old Dominion University and GSA Division of Geobiology and Geomicrobiology - nnofke@odu.edu) or Wesley Hill (GSA - hill@geosociety.org).

For donations to the fund for the site please contact Theresa Scott (SEPM - tscott@sepm.org).

Thank you very much,
Nora Noffke

Labels: action, africa, blogs, field trips, gsw

This was in last month's Scientific American: "Birth of an Ocean: the evolution of Ethiopia's Afar Depression." Great photos.

Labels: africa, oceans, plate tectonics, rift valleys, salt

Just got through watching an episode of the PBS program NOVA (which I like to refer to as the "other" NOVA). The episode was titled "Volcano under the city," and it looks at the volcano Nyiragongo in Congo, central Africa. This was the same volcano that had such a spectacular eruption in 2002, when lava flowed through the city of Goma, on the shore of Lake Kivu. The program follows UN vulcanologist Jacques Durieux on a journey through Goma and into Nyiragongo to evaluate the risk for the ~2 million people who live in the mountain's shadow. The program explores volcanic hazards including lava flows, landslides, lake overturn (a la Lake Nyos), and pockets of CO2 in low-lying areas on land. This last one provided what I found to be the most dramatic footage: Durieux tosses a signal flare into one of the ditches, and the smoke rises and flows on top of the invisible layer of CO2 below: it demonstrates dramatically how there's something invisible pooled in that ditch due to its density. There's also plenty of footage of frothing spewing blobby lava, if that's your thing. As is often the case, the narrator overpitches the dangerous aspects of the situation, and the whole hour-long show feels kind of like a hyped-up movie trailer. Certainly the situation there is dangerous, but I feel like some credibility gets lost when every word is uttered with a sense of looming menace.

Labels: africa, CO2, movies, tv, volcano