gigapan

Virtual owl pellet

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Owls are nocturnal birds of prey that eat rodents and grasshoppers, digest the good stuff, and cough up the rest in compressed “pellets” of fur, bone, and chitinous exoskeleton. I found an owl pellet in my yard a few weeks ago, and imaged it using my GIGAmacro Magnify2. I rotated it around to get multiple … Read more

Basaltic strata, faulting, and glaciation in western Iceland

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Today, let’s journey to Iceland, to a bit northwest of Reykjavík. This is a view from the top of the Grábrók cinder cone, across the valley to the east. With very few exceptions, Iceland is a big pile of basalt, and that shows through in the walls of this valley, which display a stack of … Read more

Friday fold: Smaull Graywacke at Saligo Bay, Islay

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On the western coast of Islay, Saligo Bay showcases turbidites of the Neoproterozoic Colonsay Group. The Smaull Graywacke shows Caledonian (late Ordovician) folding and cleavage superimposed on world-class graded bedding. There’s also a nice dolerite dike to examine.

Friday fold: one from the archive

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As noted previously, my colleague Declan De Paor recently retired from Old Dominion University, and I was lucky enough to inherit some of his rock samples. I’ve been making super-high resolution images of the samples ever since. Here’s a particularly striking fold, weathered out differentially. Enjoy exploring it – and have a happy final Friday … Read more

GIGAmacro sample preparation: 3 techniques

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Here are three pairs of GIGAmacro images to illustrate a few techniques I’ve used in preparing the samples and the images. The image pairs here illustrate the effects of transparent acrylic coatings, pressure-washing, and post-imaging clean-up in Photoshop. Let’s begin with a meta-ignimbrite of the Catoctin Formation, cut with a rock saw and polished using … Read more

Cobble diversity of Fetlar’s beaches

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Now that we’ve examined the geology of the outcrops at Funzie Bay on the island of Fetlar in northeast Shetland, let’s stroll along two beaches. Here we have cobbles from Funzie Beach and a small beach eroded from serpentenite and metaharzburgite of the island’s ophiolite complex. Compare. Contrast. Rejoice. Link GigaPan by Callan Bentley Link … Read more

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

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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

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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 … Read more

A virtual field trip to Portrush, Northern Ireland

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One of my favorite places in Northern Ireland is the east side of the peninsula that hosts the tourist town of Portrush. There, two early schools of geological thought engaged in a battle. The opposing sides were: the Neptunists, who thought all stratified rocks, and in particular basalt, must form from precipitation from the sea, … Read more

A virtual field trip to Rathlin Island, Northern Ireland

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Rathlin Island lies north of mainland Northern Ireland, a few miles offshore. I spent three lovely days there this past summer, investigating the geology and appreciating the wildlife (puffins and other sea birds, and seals). The geology is pretty straightforward: Paleogene basalt overlying Cretaceous “chalk” (really not so chalky here – technically, it’s the Ulster … Read more