Oil filling history of the Ordovician oil reservoir in the major part of the Tahe Oilfield, Tarim Basin, NW China

Isotopic compositions and biomarkers in crude oils from the Tarim Basin: Oil maturity and oil mixing

“…13 C values of n-alkanes were mainly attributed to the mixing of the oils derived from various sources (Jia et al, 2010;Li et al, 2010), which also supports the conclusion evidenced by the large variation of biomarkers in marine oils or bitumens Wang et al, 2008;Pan and Liu, 2009;Li et al, 2010;Yu et al, 2011). To completely unravel oil formation processes in such an old basin, there is an obvious need for new technologies or the application of a more integrated approach.…”

“…Multiple oil generation and filling stages have been proposed as the mechanism of diverse oil formation, e.g., normal, light, waxy and heavy oils occurring in the basin Gong et al, 2007;Wang et al, 2008;Pan and Liu, 2009;Jia et al, 2010;Li et al, 2010;Yu et al, 2011). Many publications documented that there are large variations in the maturity of those oils Pan and Liu, 2009;Yu et al, 2011) and secondary alteration processes also have been reported, including moderate to severe biodegradation (Wang et al, 2008;Pan and Liu, 2009;Jia et al, 2010), and gas washing or migration fractionation resulting in wax precipitation (Ma et al, 1996;Zhang, 2000;Zhang et al, 2011). Although many studies have been carried out, the understanding of the oil source, maturity and oil mixing in the Tarim Basin was not conclusive, partly because limited source rocks in the basin had been revealed by exploration practices.…”

Identification of the Kukersite-type source rocks in the Ordovician Stratigraphy from the Tarim Basin, NW China

“…It has become the biggest palaeozoic marine oil field (Tahe-Lunnan 100 million ton oil field) as a result of large-scale explorations of 30 years in the Tarim Basin. Due to the importance of Ordovician marine source rocks in the global exploration of Paleozoic petroleum resources and the con-sideration of the actual results of the basin biomarker oilsource correlation of compounds, most geochemists believe that the Middle and Upper Ordovician source rocks are the major source rocks of marine crude oil in the Tarim Basin [14][15][16][17][18][19][20]. There are a great amount of geochemical evidences such as molecules and isotope that prove the fact that the Cambrian-Lower Ordovician source rocks had significant contributions to the Lower Paleozoic petroleum systems which have been found so far [21][22][23][24][25].…”

Distribution and geochemical significance of phenylphenanthrenes and their isomers in selected oils and rock extracts from the Tarim Basin, NW China

“…The Ordovician carbonate oils from the Tabei Uplift were sourced from Paleozoic carbonate source rocks (Zhang and Huang 2005;Wang et al 2008;Pang et al 2010;Li et al 2012b). Oils in wells QL1, Ku1, and S3 were derived from Mesozoic lacustrine mudstones (Xiao et al 2004;Song et al 2015).…”

“…1) are of typical lacustrine mudstone origin (Li et al 2004;Xiao et al 2004;Song et al 2015). Oils from Ordovician carbonate reservoirs were derived from Paleozoic carbonate source rocks (Zhang and Huang 2005;Wang et al 2008;Chang et al 2013). Dibenzothiophene, dibenzofuran, and their alkylated homologues are effective molecular markers in inferring depositional environment, maturation assessment and in tracing oil charging pathways (Bao et al 1996;Wang et al 2014;Li et al 2008;Zhang and Philp.…”