dc.description.abstract | Carbonate has significant contribution in world oil and gas production. In order to explore the process and mechanisms of organic matter during burial and preservation processes in present carbonates sedimentary setting, the Guanxin algal reef, which is an intertidal zone enriched with algal organic matters in NW Taiwan, is selected as the study area. In this study, there are two sampling sites: Off shore and near shore. Samples were collected from different depths(0-5 cm, 5-15 cm, 15-30 cm and 30-40 cm)for both sampling sites. Seawater quality were examined by using a water analyzer while collecting samples. The water qualities are controlled by sea tide, whereas two sampling sites present similar results. As for Rock-Eval Pyrolysis and total organic carbon(TOC)contents, all samples show TOC, S1 and S2 below 0.5%, 0.5 mg HC/g rock, and 2.5 mg HC/g rock, respectively. Hydrocarbon potential is low due to low organic carbon content and low maturity. Off shore samples exhibit higher organic carbon content and vertical variation, organic carbon is also enriched with depth. Biomarker analysis indicate an oxic environment of all samples, leading to the poor preservation of organic matter. Meanwhile, strong terrigenous inputs were found in some samples, which might be coming from oil pollution or other highly matured terrigenous material. X-Ray Diffraction(XRD)of clay mineral and whole rock show the domination of illite, which indicate marine signal and high intensity of silicate mineral. The sources are believed coming from low metamorphic clay mineral and further influenced by chemical weathering. The variation among all samples and low carbonates content can be attributed to the incomplete diagenesis. Finally, most of the minerals belong to allochthonous material, with inconsistent input and preservation of autochthonous organic carbon. | en_US |