Friday fold: “the eye of Sauron” at Sibubule
Have a look at this week’s Friday fold – but be aware that it will be looking back!
south africa
Archean meteorite impact evidence from the Fig Tree Group in Barite Valley, Barberton Greenstone Belt, South Africa
What does the sedimentary record of a giant meteorite impact look like? Turns out it is full of tsunami breccia, fine ash, hail-like spherules, and a barium-rich ocean’s crystal precipitates. Join us in the Barberton Greenstone Belt of South Africa to learn more.
GIGAmacro views of komatiite
Erik Klemetti posted today at Eruptions about komatiite, which is apropos, considering I just finished imaging some samples of that ultramafic volcanic rock. Have a look at three samples from Barberton Greenstone Belt here, each from the 3.27 Ga Weltevreden Formation: [gigapan id=”192621″] Link GigaPan by Callan Bentley [gigapan id=”192599″] Link GigaPan by Callan Bentley … Read more
Friday fold: a miniature ramp and flat
Sometimes you find big ideas in small places. Here, a South African chert boulder mimics in miniature fold and thrust belts the world over.
A virtual field trip to examine the Peninsula Sandstone on Table Mountain
Take a virtual field trip to Table Mountain, near Cape Town, South Africa. Digital media to explore from the site include: a 3D model, 3 GigaPans, and a 360° spherical photo!
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.
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 … Read more
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 … Read more
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.
Ball & pillow and other sedimentary structures in Graafwater Formation, Table Mountain
In Cape Town for the International Geological Congress, Callan hikes up Table Mountain and finds some superb primary sedimentary structures in sands and shales of the Graafwater Formation.