TEXTURAL CHARACTERIZATION OF ROCKS

Textural characteristics are a major factor in determining the mechani cal behaviour of rocks and in the prediction of performance of rock cu tting and drilling equipment. The principal textural characteristics o f rocks are grain size, grain shape, grain orientation, relative propo rtion of grains and matrix material which were herein quantitatively m easured using a modern image analysis system. These features resulted in a texture coefficient represented by a single number for each rock specimen. In this study a range of both textural and mechanical data f or a range of rock types are given with some of the textural determina tion methodology. Correlation between textural and physical properties are also highlighted. The results of drilling tests using polycrystal line diamond compact (pin and hybrid) and impregnated diamond core bit s in the rocks are presented which demonstrate the influence of rock t exture on drillability. The rock texture can be used as a predictive f actor for assessing the drillability and cuttability, mechanical and w ear performance of rocks.