Top 10 Signs You Might be a Geologist

10. You've responded "yes" to the question, "What have you got in there, rocks?"
9. You've taken a 15-passenger van over "roads" that were really intended only for cattle.
8. You've found yourself trying to explain to airport security that a rock hammer isn't really a weapon.
7. Your rock garden is located inside your house.
6. You've hung a picture using a Brunton as a level.
5. Your collection of beer cans and/or bottles rivals the size of your rock collection.
4. You consider a "recent event" to be anything that has happened in  the last hundred thousand years.
3. Your photos include people only for scale and you have more pictures of your rock hammer and lens cap than of your family.
2. You've been on a field trip that included scheduled stops at a gravel pit and/or a liquor store.
1. You have uttered the phrase "Have you tried licking it?" with no sexual connotation involved.

Ramsay Fold Classifications

John Ramsay's Fold Classification

John Ramsay proposed a classification scheme for folds that is used to describe folds in profile based upon curvature of the inner and outer lines of a fold, and the behavior of dip isogons.

dip isogon: a line that connects points of equal inclination or dip on the outer and inner bounding surfaces of a folded layer

Class 1 - Dip isogons converge downward towards axial surface, signifying that the curvature of the outer arc is less than that of the inner arc

Class 1A - Limbs thicker than hinges

Class 1B - Layer thickness constant; parallel fold

Class 1C - Limbs thinner than hinges

Class 2 - Dip isogons are parallel, signifying that the curvature of the outer arc exactly matches the curvature of the inner arc; similar fold

Class 3 - Dip isogons diverge downward towards axial surface, signifying that the curvature of the outer arc is greater than that of the inner arc

Class 1B (parallel) and Class 2 (similar) folds are the most common folds seen in the field. Concentric folds are a special case of Class 1B (parallel) folds where the outer and inner bounding surfaces define arcs with a common center of curvature. These types of folds are common in upper crustal tectonic settings, where most deformation occurs by processes that only permit limited ductile flow of rock. Most of the deformation is accommodated by slip on bedding or layer boundaries (flexural slip folding). Class 2 (similar) folds have relative thinning of the limbs and thicking of the hinges. These types of folds are common in metamorphic terranes, where most deformation occurs by processes that permit extensive ductile flow of rock.


Sources:
Folding and Fracturing of Rocks, John G. Ramsay, 1967
Structural Geology of Rocks, 2nd Edition, George H. Davis & Stephen J. Reynolds, 1996
http://ocw.mit.edu/courses/earth-atmospheric-and-planetary-sciences/12-113-structural-geology-fall-2005/lecture-notes/part6_dctl_fldfb.pdf

Near passerine? How can you be near passerine?

Near passerine? How can you be near passerine? Doesn't that just make you non-passerine?

I know very little about bird lineages, and I recently read an article about the replacement of non-passerine birds in Europe with passerine birds. I was trying to determine what passerine versus non-passerine birds were, generally, but when I looked up woodpeckers I found that they, and several other lineages, were known also as "near passerines." My search led me to citations that stated that near passerines are a group that are believed to be related to true passerines due primarily to ecological similarities. It is thus far undetermined whether or not all near passerines are related to true passerines, but new molecular data apparently makes it appear unlikely. So, that is, briefly, a near passerine.