Boron and lithium isotopic method for tracing hydrocarbons and their by-products

Abstract

The invention relates to methods for determining the source of hydrocarbons presented in the pores of a host rock or found in contaminated groundwater. The method includes the steps of (a) determining a first isotopic composition of boron and/or lithium in one or more components within a potential source rock sample, such as kerogen, clay, or water; (b) determining a second isotopic composition of boron and/or lithium in the hydrocarbons found within the pores of a host rock sample or in contaminated groundwater; and (c) comparing the first and second isotopic compositions to determine whether the potential source rock is the source of the hydrocarbons within the pores of the host rock or in contaminated groundwater. The comparison is facilitated by using the isotope fractionation between the kerogen, clay, or water components and the bitumen component of the potential source rock, which allows one to predict the isotope composition of any hydrocarbons originating in the bitumen component of the source rock, based on the isotope composition of one of the other three phases. The method can be used to select host rock for extracting oil and other hydrocarbons, as well as in remediating groundwater contamination.

Dependencies are inferred from the claim text.