Advertisement

You are browsing the archive for south america Archives - AGU Blogosphere.

15 May 2020

Friday fold: Argentinian turbidites

Zoltán Sylvester brings us this Friday’s fold: And there’s more where that came from: These are deepwater strata of the Lower Cretaceous Rio Mayer Formation, exposed near Lago Argentino, Argentina, south of the lake’s northwest “arm,” about here. They were deformed so exquisitely during Andean mountain-building. Zoltán is a talented photographer, and you should check out more of his work here.

Read More >>


15 January 2019

Easing of selective pressure on Opuntia cacti in the Galapagos Islands

A cactus you can pet with your bare hand? Turns out it can tell you something about whether that island contains any land iguanas. A case study in the easing of natural selective pressure.

Read More >>


14 January 2019

A tale of three iguanas

As noted last week, I spent the week spanning New Year’s Eve in the enchanted isles of the Galapagos. The previous week (over Christmas) my family and I were in coastal Ecuador. I saw a total of three species of iguanas in the two locations, and they offer a neat little story of evolution. Let’s take a look. First, let’s introduce the key players: The green iguana, Iguana iguana (coastal Ecuador, …

Read More >>


8 January 2019

Geology of the Galapagos Islands

Dozens of delectable geological images from the Galapagos Islands, showing fluid basalt flows and violent pyroclastic deposits along with many primary volcanic features (and a bit of sedimentology thrown in for good measure).

Read More >>


26 January 2018

Friday fold: eastern Andes

This image graces the cover of the new report, Challenges and opportunities for research in tectonics: Understanding deformation and the processes that link Earth systems, from geologic time to human time. A community vision document submitted to the U.S. National Science Foundation: Make it bigger by clicking it The photo is of a landscape in the Eastern Cordillera of the Andes, southern Peru, showing folded Permian carbonates cut by a …

Read More >>


21 April 2016

Firsthand reports from Canoa, Ecuador after the quake

Callan’s mother-in-law lives in one of the most strongly-shaken regions of Ecuador. Here, she and her boyfriend recount the experience of the earthquake Saturday night and its aftermath. Includes 8 photos from the scene.

Read More >>


7 April 2016

New GIGAmacro images of rock samples

Another week, another batch of new images produced on my home-based Magnify2 imaging system from GIGAmacro. Leptaena brachiopod in (Mississippian?) limestone from Montana: [gigapan id=”185784″] Link Here’s the flip side of the same sample, with a lot of fenestrate bryozoans to see: [gigapan id=”185809″] Link Fault breccia from the Corona Heights Fault of San Francisco: [gigapan id=”185868″] Link Amygdular metabasalt from the western Sierra Nevada of California: [gigapan id=”185894″] Link …

Read More >>


20 March 2016

3D and GIGAmacro views of Cerro Toro conglomerate

Six years ago, I went to Patagonia*, and collected this sample there. It’s a deep-water conglomerate from the Cerro Toro Formation. I’ve imaged it here in two media: the Sketchfab-hosted (Photoscan-generated) 3D model, and GigaPan-hosted (GIGAmacro-generated) views of both the front and the back. In combination, these three digital items can probably give you a pretty good sense of the sample: [sketchfab id=”7fe94fbacda948beaae4737afb2f589c” start=”0″ spin=”” controls=”0″] [gigapan id=”185276″] Link [gigapan …

Read More >>