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火山岩地球化学特征与构造背景关系十分密切。经分析，张强凹陷及邻区大洼昌图凹陷的火山岩具有以下特征：（１）火山岩都为中酸性，以碱性玄武岩系列为主；（２）张强凹陷火山岩属既有钾质也有钠质的碱性玄武岩，另外还有钙碱性和大陆型拉斑玄武岩，邻区大洼昌图凹陷火山岩全部为钠质碱性玄武岩；（３）张强凹陷和邻区大洼昌图凹陷火山岩的球粒陨石标准化稀土元素分配曲线向右倾斜，轻稀土富集；（４）微量元素ＺｒＣｅ，ＺｒＬａ图解上，张强凹陷与大洼昌图凹陷差别明显。这些特征表明，张强凹陷及邻区大洼昌图凹陷的火山岩均为大陆裂谷活动的产物，但张强凹陷发育时间稍早；张强凹陷与大洼昌图凹陷火山岩的岩浆来源不同，应分属不同的构造单元。
The geochemical characteristics of volcanic rocks are closely related to the tectonic setting. The volcanic rocks in Zhangcha Sag and Dachang Changtu Depression in the neighboring area have the following characteristics: (1) volcanic rocks are all acidic and dominated by basaltic basalts; (2) volcanic rocks in Zhangqiang sag belong to both potash and sodium Alkaline basalts, calc-alkaline and continental tholeiite basalts, and the volcanic rocks in the Dachangchaitu Sag of the adjacent area are all sodium alkaline basalts; (3) the volcanic rocks in the Zhangcha Sag and the Dachangchaitu Sag of the neighboring area The normalized distribution of rare earth elements in the meteorites is inclined to the right and is enriched in light rare earths. (4) In the diagrams of trace elements ZrCe and ZrLa, there is a clear difference between the Changqiang Sag and the Dachang Changtu Sag. These characteristics indicate that the volcanic rocks of Zhangqiang Sag and Dawa Changtu Sag in the adjacent area are the products of continental rifting activity, but the development time of Zhangqiang Sag was earlier. The volcanic rocks of Zhangqiang Sag and Dachang Changtu Sag have different sources of magma, Different structural units.