| Abstract: | The natural thermoluminescence of samples of limestone from within and near the Charlevoix meteorite impact structure indicates that the effect of impact, strain due to faulting, low grade thermal metamorphism, and recrystallization can often be distinguished on the basis of the shape and either the total emission or amplitude of the peaks of the thermoluminescence curves. Impact causes a reduction of thermoluminescence which is detectable in the Charlevoix structure for about 10 Km outside the known limits of shatter cone development. It is inferred that thermoluminescence investigations should provide a useful means of investigating other impact structures. Impact effects on quartz rich rocks appear to be somewhat similar to the effects in calcareous rocks, but a fundamental difference in the electronic properties of shocked quartz and calcite demonstrate that identical effects should not be anticipated. |
