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道孚盆地位于中国四川西部鲜水河断裂带次一级的道孚和乾宁两条断裂左旋右阶的阶区内，是属拉分型盆地。本文根据１：５万活断裂地质填图的资料，从盆地的性态与地层的分布和演化入手，来研讨鲜水河断裂带次一级断裂的运动特征与演化过程。盆地为乾宁断裂、道孚断裂和子龙断裂（东西向）所围限，位于道孚县城关附近，北西起格日经道孚县城到格西乡泥湾一带，是一三角形的狭长河谷盆地，长约１７公里，宽１—３．５公里。地势南东高北西低，盆地北西部鲜水河和纽日河的汇合处，是现代的沉积中心，沉积了大片全新世晚期的冲、洪积层（Ｑ）。在格西乡附近是三角形盆地的最宽处，地势北东高南西低。盆地北东最高处为中更新世的冲洪积堆积（Ｑ），向南西为一宽大的扇形斜坡，由晚更新世早、中期冲、洪积层组成（Ｑ），斜坡下为现代河谷全新世早、中期的冲、洪积层（Ｑ）。道孚断裂、乾宁断裂和子龙断裂，都是第四纪以来的活动断裂。由于它们不同时期的活动与演化，所沉积的相应沉积物是断裂组合活动空间的具体反映。据此从盆地的形成、断裂组合活动可划分出两个阶段：第一阶段在中更新世之后，晚更新世之前。那时乾宁断裂北西段的东支断裂开始活动，切断金卡附近的中更新世冲、洪积层（Ｑ）；同时伴随运动的?
The Daofu Basin is located in the second order of the Xianshuihe fault zone in western Sichuan, China, and belongs to the subdivision basin in the order of the two zones of Daofu and Qianning faults with the left-hand faulted zone. Based on the data of 1: 50000 active fracture geological mapping, this paper discusses the movement characteristics and evolution of the secondary fracture of the Xianshuihe fault zone from the characteristics of the basin and the distribution and evolution of the strata. The basin is surrounded by the Ganning fault, the Daofu fault and the Zilong fault (east-west direction), and is located near the Daguan County's Guanghuan. The northwest rising grid passes through Dofu County to the mud bay of Gexi Township. It is a triangular narrow valleys , About 17 km long and 1-3.5 km wide. The terrain is high in the south, low in the north and low in the west, and the confluence of the Xianshuihe and Niu Rihe in the northwestern part of the basin is a modern sedimentary center that deposits large amounts of red and alluvial deposits (Q) in the late Holocene. In the vicinity of Geshee Township is the widest point of the triangular basin, the topography of North East High South West low. The highest point in the northeast of the basin is the mid-Pleistocene alluvial accumulation (Q), which is a large fan-shaped slope to the south and west. It consists of early, mid-flood and alluvium layers (Q) in late Pleistocene, Early, mid-red, alluvium (Q). Daofu fault, Ganning fault and Zilong fault are the active faults since Quaternary. Due to their activity and evolution in different periods, the corresponding sediments deposited are the specific reflection of the fracture combination activity space. Based on this, two phases can be distinguished from the formation and fault assemblage of the basin: the first stage is after the middle Pleistocene and before the late Pleistocene. At that time, the eastern branch of the northwestern segment of the Ganning fault started its activities and cut off the Middle Pleistocene red and alluvial layers near the gold card (Q). At the same time,