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Friday Rocks 1

Lately I've been posting some photos from my research trips to Instagram and I thought why not repost them here in better quality. Every Friday I'll post a new photo of a rock landscape with some description and light interpretation. Enough talk, let's see the rocks.

Lens cap is 72 mm
Here is a piece of laminated "gritty dolomite" in float from Naukluft-Zebra Park, Namibia. Gritty dolomite is a fault core rock that deformed via granular flow during coseismic slip. Laminae resemble flow bands. Here a small fault has offset this rock with apparent left-lateral motion. You can see small drag folds in the finer laminae on the left side of the photo, a feature which is noticeably absent from the courser laminae. This demonstrates a rheological difference between course and fine laminae where fine bands are relatively softer compared to the course bands. The course grains are composed of neocrystallized dolomite, magnetite, and quartz.

Click here to see the picture on Instagram

Have an instagram? Follow me here. You'll get a preview of the rocks, more field photos, plus more random photos I take.

Want more Friday rock pictures? Check out Callan Bentley's Friday Fold series.

Stratigraphy.net | Impressum

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