Showing posts with label structural geology. Show all posts
Showing posts with label structural geology. Show all posts

Thursday, 31 March 2011

slickensides vs slickenlines

In my current job I am learning any number of interesting things as I look things up in the course of editing so as to be certain that terms are being used correctly. Today's noteworthy subject to look up is the difference between the terms "slickensides" and "slickenlines". I only recall the former from my undergraduate structure courses, and neither term has come up in my own research since then. There was a time when looking up such geologic terms meant reaching for a geologic dictionary. These days it can sometimes be more effective to reach for the internet. I just found an interesting article which nicely clarifies the difference between the two words, and why there are two such closely related words in the first place.

Slickensides refers to the planar, polished, surface of a fault plane (the polishing occurring when the rocks rub past one another. Slickenlines, on the other hand, refers to the liner scratches which occur on such a surface, as a projection on one side of the fault scratches a grove onto the other. Most of the slickensides I have seen in the field contained slickenlines. No wonder my teachers and classmates simply used the term "slicks" when discussing them informally in the field.

Friday, 14 January 2011

fablous fold photos on line

For those of you who missed today's Friday fold photos you might want to go click on this link and spend time admiring the really pretty folds from the new Structural Geology textbook by Haaken Fossen at the University of Bergen, Norway. If the book is half as nice as the on-line photos from it it would be a wonderful addition to any library.