Detail of Volcán Irazú, Costa Rica. For an overview see Image:DirkvdM_irazu_2.jpg.

I asked what this is at w:Talk:Volcanology#Rock and got the following reply:

Looks like an w:unconformity, a more recent lava flow on top of older material. The tilting - craters result from the collapse of a volcanic core which creates considerable local faulting and distortion, so folded or tilted and distorted lava layers are to be expected around a caldera collapse. Vsmith 13:12, 31 August 2006 (UTC)

So it's an uncomformity, something I can identify with. :)

Camera location	9° 58′ 42.9″ N, 83° 51′ 00.7″ W	View this and other nearby images on: OpenStreetMap	9.978583; -83.850194

(precision: 50 m)

Original filename: 040130_4196r.jpg

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