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Posts treating: "Africa"

Thursday, 13 April 2017

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Nuovi attori alla divergenza tra uccelli e coccodrilli 

Theropoda [2017-04-13 21:30:00]  recommend  recommend this post  info
Ricostruzione composita dei resti di Teleocrater (da Nesbitt et al. 2017). I diversi colori nella ricostruzione scheletrica riflettono i diversi esemplari utilizzati come riferimento. Tra gli animali viventi, i coccodrilli sono quelli più strettamente imparentati con gli uccelli. Questo legame, che fonda il clade Archosauria (che, in versioni minoritarie, è detto Avesuchia, per usare

Stromatolite from Mauritania 

Louisville Area Fossils [2017-03-30 03:30:00]  recommend  recommend this post  (137 visits) info
This fossil stromatolite was found at Atar Mauritania. Fossil dates to the pre-Cambrian Period. It was on display at the Musée de Mineralogie (Mineralogy Museum) located at the MINES ParisTech, 60 Boulevard Saint-Michel 75006 Paris France (August

Chenan il Barbaro 

Theropoda [2017-03-28 21:06:00]  recommend  recommend this post  (2 visits) info
Ogni aggiunta, per quanto frammentaria, al record fossile dei dinosauri africani è sempre benvenuta. E se poi si tratta di un theropode dalla fine del Cretacico africano, è due volte benvenuta. Longrich et al. (2017) descrivono un dentale frammentario (e riferiscono due denti al medesimo taxon) dai fosfati del Marocco. I fosfati marocchini hanno un'età compresa tra il Maastrichtiano e l'Eocene

Friday fold: Sheba Mine sample 

Mountain Beltway [2017-03-10 13:52:29]  recommend  recommend this post  (31 visits) info
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 the place, nestled between sepia-toned photographs and old lanterns and rusty picks. I wonder what

Come nuotava Spinosaurus? 

Theropoda [2017-03-02 20:41:00]  recommend  recommend this post  (27 visits) info
Postura semi-eretta bipede per Spinosaurus, modificato da Ibrahim et al. (2014). Non mi pare sia così assurdo... In un recente post, ho discusso l'ipotesi quadrupede proposta da Ibrahim et al. (2014) su Spinosaurus, ed ho concluso che il femore e tibia di Spinosaurus, come pubblicato da Ibrahim et al. (2014, e informazioni supplementari) non mostrano particolari adattamenti per un nuoto a

The rise of the bipedal Spinosaurus 

Theropoda [2017-02-25 12:27:00]  recommend  recommend this post  (41 visits) info
Negli uccelli a coda corta, i muscoli ileofibulari generano una forza estensoria che controbilancia lo spostamento anteriore del baricentro, mantenendo una postura semi-eretta. Il bauplan (il modello generale della struttura corporea) dei theropodi ha una serie di vincoli che incanalano la traiettoria evolutiva dei vari gruppi, anche quando questi apparentemente deviano marcatamente gli

Banded iron formation in Barberton Mountain Land 

Mountain Beltway [2017-02-02 15:41:37]  recommend  recommend this post  (7 visits) info
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

Y-shaped joints on a basalt flow, Lake Mývatn, Iceland 

Mountain Beltway [2017-01-25 15:31:41]  recommend  recommend this post  (2 visits) info
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

More Messengers from the Mantle 

Mountain Beltway [2017-01-11 13:00:54]  recommend  recommend this post  (2 visits) info
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 pretty, I think you’ll enjoy viewing them just the same. Let’s start with a gargantuan

An Anthropocene Journey 

dot Earth [2016-11-08 17:08:23]  recommend  recommend this post  (24 visits) info
Humans have become a planet-scale disruptive force. What

An Anthropocene Journey 

dot Earth [2016-11-08 17:08:23]  recommend  recommend this post  (1 visit) info
Humans have become a planet-scale disruptive force. What

Vascoceras Ammonite Fossil 

Louisville Area Fossils [2016-11-08 06:42:00]  recommend  recommend this post  (5 visits) info
This image is of a Vascoceras (Paravascoceras) cauvini Chudeau ammonite fossil.  Animal existed in Cretaceous Period. The fossil was found in Damergou Niger Africa. Displayed at Muséum National D'Historie Naturelle Jardin Des Plantes Paléontologie et Anatomie Comparée in Paris, France (August

Friday fold: “the eye of Sauron” at Sibubule 

Mountain Beltway [2016-10-28 14:10:07]  recommend  recommend this post  (6 visits) info
Have a look at this week's Friday fold - but be aware that it will be looking

Archean meteorite impact evidence from the Fig Tree Group in Barite Valley, Barberton Greenstone Belt, South Africa 

Mountain Beltway [2016-10-26 19:46:07]  recommend  recommend this post  (11 visits) info
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

GIGAmacro views of komatiite 

Mountain Beltway [2016-10-24 19:11:06]  recommend  recommend this post  (37 visits) info
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: Link GigaPan by Callan Bentley Link GigaPan by Callan Bentley Link GigaPan by Callan Bentley And, while we’re at it, here’s one from the Red Lake Greenstone Belt (~3.0

Friday fold: a miniature ramp and flat 

Mountain Beltway [2016-10-21 15:18:53]  recommend  recommend this post  (10 visits) info
Sometimes you find big ideas in small places. Here, a South African chert boulder mimics in miniature fold and thrust belts the world

Tension gashes in Malmesbury metasediments near Sea Point Contact 

Mountain Beltway [2016-09-08 15:27:26]  recommend  recommend this post  (6 visits) info
A small structural geology treat - several en echelon arrays of tension gashes (quartz-filled veins) in Malmesbury Group metasediments, Sea Point, South

Viewing the Sea Point migmatite through the lens of GigaPan 

Mountain Beltway [2016-09-03 07:10:23]  recommend  recommend this post  (3 visits) info
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

Friday fold: isoclinal fold in ferruginous pelite and chert of the Fig Tree Group 

Mountain Beltway [2016-09-02 08:15:18]  recommend  recommend this post  (6 visits) info
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

Archean microbial mats in the news and in GigaPan 

Mountain Beltway [2016-09-01 08:25:18]  recommend  recommend this post  (146 visits) info
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 | Impressum