The ND112 Complex

INTRODUCTION A recently developed field area, designated “ND112”, exhibits a fascinating assemblage of geologic environments reflected in a myriad of deskcrops. We have identified 14 unique geologic horizons occurring over an area of 4.5 by 6 meters. In this report we briefly describe, map, and give preliminary interpretations on the history of the ND112 region. […]

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Geophoto: petrified wood

What rolls down stairs, alone or in pairs? That’s right kids, it’s Log! This half-meter diameter log was buried some 200 Myr ago and its organic content was replaced by silica (a process called permineralization). One thing I’ve always wondered: If we split wood parallel to the long axis, why is it so common for […]

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Geophoto: Antelope Island

Today’s contribution to the geology photo week geomeme is Antelope Island. This shot was taken on approach into Salt Lake City. Antelope Island is one of the ranges that makes up the Basin and Range Province of the western United States. The island is particularly photogenic as it is surrounded by the Great Salt Lake, […]

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Geophoto: pink salt

Round three of this week’s geomeme of a picture-a-day (previous entries here and here) features halite, a.k.a. rock salt! Pink (or pinky orange) halite, to be more specific. The mine, run by American Rock Salt, is the largest operating salt mine in the United States (3+ million tons annual production). This pink halite is located […]

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Geophoto: Centralia coal fire

Continuing the geology photo week started with yesterday’s dikes and pillows, today’s picture is from the borough of Centralia, PA, where an underground coal fire has been burning since 1962. The heat and volume change caused roads to crack and warp and left the ground unstable in some areas. As a result, the borough has […]

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500km from Sudbury

Impact craters are ubiquitous features on solid bodies in the solar system, but on Earth they’re rather annoyingly quickly eroded. The impact crater at Sudbury, Ontario is 1.85 Byr old with an initial diameter of between 150 and 260 kilometers. Sudbury remains an oblong scar on the Canadian shield, but little remains (or has been […]

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Warren Dunes, briefly

In July my friend visited Notre Dame to run in the Sunburst (Half-)Marathon, and while he was around we took a trip to Warren Dunes State Park. Dunes occur over a broad area in the eastern shore of Lake Michigan (Sleeping Bear, Silver Lake, Cowles Bog, etc.), with Warren Dunes being one of the largest […]

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