The South China Cea (SCS) and its margins constitute a frontier area in the global search for hydrocarbons. One of the most important areas of the SCS is the Pearl River Mouth (PRM) basing, which seismic stratigraphy indicates contains up to 10,000 m of Cenozoic sediments. Standard biostratigraphy often lacks the resolution and accuracy necessary for hydrocarbon exploration and production due to the complicated nature of sedimentation in the PRM basin. The authors are applying chemical stratigraphy to achieve an alternative, higher resolution stratigraphy in the PRM. Stable isotope analysis has been performed on Miocene reef carbonate sections in five exploration wells of the PRM basin. Their results indicate that such geochemical measurements represent a potentially powerful tool for providing high resolution stratigraphic correlation of Neogene exploration sections of the South China Sea. Isotope data from whole rock analyses show that {delta}{sup 18}O values range from {minus}2.9-{minus}6.5{per thousand}(PDB) and {delta}{sup 13}C values range from {minus}7.1-4.9{per thousand} (PDB). The {delta}{sup 18}O and {delta}{sup 13}C records provide a preliminary high resolution stratigraphic zonation defined by three intervals: A,B, and C. Intervals A and C have similar isotopic signatures for both oxygen and carbon. However, the {delta}{sup 18}O values for interval B aremore » 1-2{per thousand} (PDB) more negative than interval A and C, and the {delta}{sup 13}C values of B are as much as 6-8{per thousand} (PDB) more negative than A and C. Cross-correlation analysis of the isotopic signatures indicates that the {delta}{sup 18}O and {delta}{sup 13}C signals of these wells have very high cross-correlation coefficient values averaging 0.65 at zero lag, even though the lithological characteristics are quite different for each well. These results imply that the isotopic signals are independent of the lithological properties of the PRM wells.« less