A computer system including a processor executing processor-executable code stored in a non-transitory processor-readable medium, causing the processor to receive a signal via an input port, including data indicative of an amount of a combustion product produced by a sample of drill cuttings subjected to oxidation at a constant temperature (1000° C. or 650° C. 100° C.) as a function of time and process the data according to a predetermined logic to: locate a peak in the amount of the combustion product produced at a set of instants in time; correlate the set of instants in time with the presence in the sample of an organic carbon from a contaminant or light volatile carbon molecules, organic carbon, and inorganic carbon; calculate at least one of an amount of contaminant, a total amount of organic carbon, and a total amount of inorganic carbon; and output a signal indicative of the calculated amount.