Abrasivity test results from Lao-PDR: verification of the CAI-LCPC abrasivity classification

Simple abrasivity testing has been carried out on a sequence of arkosic and sub-arkosic sandstones, siltstones and mudstones with dominant sericite and ferruginous cements. Abrasivity classifications systems have been proposed by Thuro & Käsling (2009), which correlate the Cerchar index (CAI) with the LCPC abrasivity index (ABR), which appears to show linear correlation between the CAI and the ABR. Many of the recent studies are based on a European data of rocks bound by silica. On a global scale cements other than silica are present. The data presented in this short paper is from a sedimentary sequence dominated by sericite and ferruginous cements. The LCPC tests have been carried out according to AFNOR NF P94-430-2 and the Cerchar tests were carried out using a steel pin of hardness 200 kg/mm2 along natural and sawn surfaces for 10 mm. Despite a weak cement (sericite of Moh’s hardness 2.5) and generally low quartz content for sandstone the abrasiveness for the sandstones were equal to those recorded for alpine granites and gneisses.