by: Charles O’Dale
Within this website I have documented my explorations of terrestrial impact sites on our planet. My data here will illustrate the shock-metamorphic effects in terrestrial rocks caused by hypervelocity impacts .
- IMPACT CRATER IDENTIFICATION – Geologic confirmation for an impact event:
- CRATER FORMATION – Impact involves the transfer of massive amounts of energy to a relatively small area of the Earth’s surface, in an extremely short period of time (Kinetic energy). Three stages of crater formation:
- contact & compression;
- excavation; and
- CRATER CLASSIFICATION – On this planet, impact craters are divided into three basic morphologic subdivisions:
- simple craters;
- complex craters; and
- peak ring craters.
- CRATER EJECTA – When the crater formation process ends, the resulting circular structure and the surrounding area is covered by an ejecta blanket.
- CRATER RIM – Documentation of surviving crater rims on this planet.
- CRATER SHAPE – Why are impact craters almost always round? (or polygonal?)
- GEOLOGICAL PERIODS vs IMPACT – R. A. F. Grieve and P. B. Robertson 1979 documentation of known impact craters.
- CANADIAN CRATERS – Documented in 1967 & 1975.
- PLANET VS CRATER SIZE – The primary factors governing the size and shape of impact craters are:
- impact energy;
- gravity; and
- properties of the target.
- CRATER GLOSSARY