Analytical electron microscopy of shock veins from the Catherwood L6 chondrite
University of New Brunswick
The commonly accepted theory for the formation of shock veins is that they are caused by shock pressure due to a shock wave passing through the body. More recently, people have begun to think that frictional heat contributes to the formation of these veins. Evidence supporting this theory includes the shearing and displacement of grains along the veins. The sheared grains are those composed of metal and troilite as they have a lower melting temperature. The Catherwood L6 chondrite was analyzed on the JSM 6400 digital scanning electron microscope and the petrographic microscope. Over 20 examples of shearing and displacement of grains were recognized which ranged from 6 μm-0.55 mm in length. This displacement of grains indicates there has been movement along the veins which would, in turn, produce heat. This frictional movement, coupled with shock pressure, is most likely the cause of the formation of shock veins.