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Ｐｂ、Ｓｒ、Ｎｄ同位素体系研究表明沥青与寒武纪、奥陶纪地层中的干酪根具有明显的同位素组成差异，表明来自异源。沥青Ｐｂ同位素组成具有明显的幔源与壳幔混合特征，而干酪根显示出壳源特征。沥青与干酪根的Ｎｄ同位素组成也存在着明显的差别，反映出老地壳源与新地壳源的明显差别。来自柯坪隆起大湾沟沥青的Ｎｄ－Ｓｒ同位素体系给出了晚元古的相关等时线，年龄分别为８７２Ｍａ与１１９５Ｍａ，可能代表了沥青的最早形成年龄。但来自塔北隆起的沥青其Ｓｍ－Ｎｄ体系显示出介于大湾沟沥青与干酪根之间的混合相关，表明具有壳源与幔源的二元混合成因。Ｒｂ－Ｓｒ和Ｐｂ－Ｐｂ等时线趋向和Ｐｂ模式年龄还给出加里东期（～４４０Ｍａ）和印支期（～２５０Ｍａ）的原油运移与沥青沉淀年龄信息。Ｎｄ模式年龄还表明柯坪－阿克苏地区存在太古宙基底（３．２－２．５Ｇａ）。塔里木油藏受深断裂控制。
The studies of Pb, Sr and Nd isotopes indicate that there is a clear isotopic composition difference between kerogen and Cambrian and Ordovician strata, indicating that they originated from heterologous sources. Bitumen Pb isotopic composition has obvious mantle source and crust-mantle mixing characteristics, while kerogen shows crustal characteristics. There is also a clear difference in the Nd isotopic composition of bitumen and kerogen, which reflects the significant difference between the source of the old crust and that of the new crust. The Nd-Sr isotope system of the Dawangou bitumen from the Keping uplift gives the correlations of the Late Proterozoic with isochron age of 872Ma and 1195Ma respectively, which may represent the earliest age of formation of bitumen. However, the Sm-Nd system of bitumen from Tabei uplift shows a mixed correlation between bitumen and kerogen in Dawangou, indicating a binary mixing origin of crust and mantle source. Rb-Sr and Pb-Pb isochron trends and Pb model ages also provide information on crude oil migration and asphaltene precipitation ages in the Caledonian (~ 440 Ma) and Indosinian (~ 250 Ma) years. The age of the Nd model also indicates the existence of Archean basement (3.2-2.5Ga) in the area of Keping-Aksu. The Tarim reservoir is controlled by deep faults.