Size, Location and Time of Initiation of Primary Defects in Rocks under Impact Destruction

Resumo

Samples of rocks with different physical properties (three kinds of granite, marble and quartzite) were subjected to destruction by impacts. Fractoluminescence was recorded on the damaged surface, and amplitudes and frequencies of series of light pulses were determined. On all test samples, initiation of intergrain cracks was observed. Defects on the surface of grains in granite samples had two typical sizes conformable with defects in quartz and spar, while uniform content minerals (marble and quartzite) features unimodal distribution of sizes of defects on the surface of grains.