geology

Aerial view of the Grabens, Canyonlands National Park

Do You Know Which Rocks Are Metamorphic?: Phyllite

Folds is A wave-like geologic structure that forms when rocks deform, There are alot of types of folds, Check it out for more info and amazing photos

Aerial View of Colorful Namibia, Africa

Fragment of Acasta gneiss The Acasta Gneiss is a tonalite gneiss in the Slave craton in Northwest Territories, Canada. The rock body ...

The total throw across a fault zone may not occur entirely on a single fault strand but distributed onto several strands or accommodated by distributed deformation (drag folding) within or adjacent to the fault zone. This fault zone outcrop is in an openpit lignite mine in the late Miocene–Pliocene Ptolemais Basin, West Macedonia, Greece.

This is my final post on the pre-GSA-Minneapolis structural geology field trip to the Superior Province. The photo above shows a roadcut exposure of boudinage in xenolith-bearing Vermillion Granitic Complex. Here’s another, smaller, more brittle example of boudinage, from another site, the following morning: Gee, it only took me 1.5 years to blog that trip in its entirety… Sheesh!

Tipping your tension gash – Mountain Beltway

Meanders and ox-bow lakes in a flood plain.

High/Low Sulphidation Epithermal Silver/Gold Copper Porphyry Deposits

Tension gashes are small veins that open up when rocks get stretched. Often, they are arrayed en echelon with respect to other tension gashes, all oriented in the same direction. Here is a sample o...