Oilfield waters represent an important source of lithium resources to meet increasing global demand. However, the distribution of Li resources in the western Qaidam Basin is still unclear, and the enrichment mechanism of Li remains to be explained. In this study, we present new hydrochemical data for all the oil-bearing anticlines in the Qaidam Basin. Oilfield waters in the Nanyishan and Dafengshan oilfields are characterized by Li concentrations ranging from 110.1 to 237.5 mg/L, and Mg concentrations ranging from 0.70 to 1.52 g/L. These concentrations are readily recovered and represent a key target for oilfield water exploitation in the future. In oilfield water samples from the Qaidam Basin, δ⁷Li values show large variation, possibly implying multiple sources of Li, including residual water from ancient lakes, alpine snow water infiltrating along deep faults, springs, and deep hydrothermal fluids. δ⁷Li values of the oilfield waters from Nanyishan and Dafengshan are lower than those of the river and spring water samples, but close to those of volcanic rocks around the world. These results indicate that the oilfield waters with significant Li-enrichment are associated with local hydrothermal activity. This is the first time that the δ⁷Li data of oilfield waters in the Qaidam Basin have been reported. It appears that δ⁷Li is a good tracer for determining the origin and the key controlling factors of Li accumulation processes in oilfield waters.

油田水域是满足日益增长的全球需求的锂资源的重要来源。然而，柴达木盆地西部锂资源的分布尚不清楚，锂的富集机制仍有待解释。在这项研究中，我们提供了柴达木盆地所有含油背斜的新水化学数据。南翼山油田和大凤山油田油田水的特征是锂浓度为110.1～237.5 mg/L，镁浓度为0.70～1.52 g/L。这些浓度很容易回收，是未来油田水开采的关键目标。柴达木盆地油田水样中δ ⁷Li值变化很大，可能意味着Li的多种来源，包括来自古湖泊的残余水、沿深断层渗入的高山雪水、泉水和深部热液。南夷山和大凤山油田水的δ ⁷ Li值低于河流和泉水样品，但与世界各地的火山岩相近。这些结果表明，具有显着富锂的油田水与当地的热液活动有关。这是柴达木盆地油田水域δ ⁷ Li数据首次报道。δ ⁷ Li似乎是确定油田水域Li成藏过程的起源和关键控制因素的良好示踪剂。