These shock metamorphic effects are characteristic of impact and do not occur in natural materials formed by any other process.
In addition, geochemical methods are used to find traces of the meteoritic projectile in impact melt rocks and glasses.
The most obvious criterion is the presence of shatter cones, conical fractures with diverging striations along the length of the cone.
Orientations of the cone apices were originally in the direction of the impact object and thus served as indicators of the amount of tilt in the beds subsequent to impact, some beds even overturning (Manton 1965; Howard and Offield 1968).
The kinetic energy of the impacting meteorite or asteroid is converted into heat, sound, and mechanical energy---the projectile explodes on impact.
The catalog of Canadian craters of confirmed meteoritic origin has been brought to 21 with the recent discovery of Haughton Dome on Devon Island (Robertson and Mason 1975). More recently, similar structures have been identified totally subsurface through drilling operations in the Williston Basin on the U. During the 1960's it was sometimes heatedly debated whether such structures were volcanic or meteoritic in origin.
Located in Siberia some 600 km from the nearest recent volcanoes, its nearly perfect circularity 18 km in diameter has been studied both by satellite and ground observation. impact structures have been suggested over the years: Meteor (Barringer) Crater, Arizona (Figure 1); Kentland structure, Indiana; Japhtha Knob, Kentucky; Wells Creek Basin, Tennessee; Serpent Mound, Ohio; and Crooked Creek, Missouri (Middlehurst and Kuiper 1963).
At such speeds, the projecticle explodes on impact and carves out a round bowl-shaped depression on the surface. How can you distinguish an impact crater from a volcanic crater?
Volcano craters are above the surrounding area on mountaintops while the craters from impacts are below the surrounding area with raised rims.