A rock sample is first pulverized, weighed into a 100 ml flask and treated with hydrochloric acid to dissolve carbonate mineral species. Once the reaction is complete, the sample is transferred to a microfibre filter paper using a Millipore filtration apparatus. The filter paper (with the sample) is then placed in a crucible and combusted in a LECO C230. Carbon dioxide generated by the combustion of organic matter in the sample is quantitatively measured using an infrared detector. This quantitative measurement is reported as the percentage of total organic carbon (TOC). TOC above 1% may have the capacity to be a hydrocarbon source rock. Below 1% TOC, the quantity of hydrocarbons—even if generated—is usually too small to overcome absorption on the kerogen-rock matrix, meaning no expulsion can occur.