When touring the geology of the Barberton Greenstone Belt last August, our group visited the Sheba Mine, a gold mine high in the hills. Their geologist kindly showed us around and allowed us to visit his history-laden office. I have no idea where this sample originated, but it was the only fold I saw in … Read more
Banded iron formation is an “extinct rock” that can be found in ancient marine strata such as those found in the Barberton Greenstone Belt. Visit an outcrop on the Barberton GeoTrail and contemplate the bizarre anoxic world that Earth used to be.
A basalt flow in Iceland shows both enticing pahoehoe and fractures with a Y-shaped intersection pattern. Comparisons to bread loaves and east Africa suggest a reason why.
Since I showed off the 3D kimberlite intrusion breccias yesterday, I feel as if I owe you some other photos from that lovely exhibit at the IGC. I apologize for the poor quality of these photos – the gorgeous samples were behind glass and brightly lit, which made photography difficult. But the rocks are sooooooooo … Read more
While in Cape Town for the 35th meeting of the International Geological Congress in August/September, I was delighted at the “Messengers from the Mantle: Craton Roots and Diamonds” exhibit on kimberlites. It was a world-class collection of excellent specimens that traveled to the Congress from across the city at the University of Cape Town. I … Read more
Have a look at this week’s Friday fold – but be aware that it will be looking back!
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.
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
Sometimes you find big ideas in small places. Here, a South African chert boulder mimics in miniature fold and thrust belts the world over.
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!