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塔中地区火成岩形成于早二叠世末，其产状包括层状火山岩、火山岩颈、岩脉等。对各类火成岩体的地震反射特征进行了描述。层状火山岩分布于下二叠统顶部，其厚度较薄，在地震剖面上表现为两个近平行的低频高振幅强反射同相轴；火山岩颈呈不规则柱状体刺穿震旦至石炭纪地层，并直接与二叠纪层状火山岩相接，古地貌显隆起特征，内部呈杂乱反射；岩脉一般由与层理斜交的两个强反射同相轴组成，常成组发育并呈Ｖ形或凹槽状反射。与火成岩有关的圈闭类型主要有岩颈刺穿圈闭、岩颈上覆地层中的差异压实背斜或披覆背斜、拱张背斜及岩脉侧向遮挡圈闭等。
Tazhong area igneous rocks formed at the end of the Early Permian, its occurrence includes stratiform volcanic rocks, volcanic rocks, dikes and so on. Seismic reflection features of various igneous rocks are described. Layered volcanic rocks are distributed at the top of the Lower Permian and are thin in thickness. They are characterized by two near-parallel low-frequency, high-amplitude and strong-reflex events in the seismic profile. The volcanic rocks are characterized by irregular columns piercing the Aurora to Carboniferous strata , And directly connected with the Permian lamellar volcanic rocks. The paleogeomorphology is obviously uplifted and the interior is disorderly reflected. The dikes are generally composed of two strong reflection axes oblique to the bedding, and often form a group with V-shaped Or groove-like reflection. The types of traps associated with igneous rocks are mainly the rock-pierced traps, the differences in the overlying strata of rock strata, the compacted anticlines or draped anticlines, the arcuate anticlines, and the lateral occlusion traps of the dikes.