The Cenozoic foreland basin at the southwestern Tarim basin was inflicted by both N-S compression of the west Kunlun orogen and northward indentation of the Pamir, which led to significant variations in structural architecture and deformation style. New results from interpretations of seismic profiles in the east segment of the basin are presented here to discuss such spatial variation in structural deformation and temporal variation in structural evolution. The results suggest that the segment commonly exhibits significant northward thrusting, coupled with flexural basin subsidence. Broad fold-and-thrust belt (FTB) is evidenced in the profiles with its front reaching Jiede anticline, resulting in a structural architecture of superposition of the FTB and foredeep of the flexural basin. In the vertical view, the segment is featured by basement-involved deformation belt overlain by detachment deformation belt. The first row of the deformation belt presents spatial variation in structure. The west Kedong portion exhibits anticlines controlled by thrust wedge that has been reworked by dextrally strike-slipping. In contrast, the east Keliyang portion is featured by mainly thrust deformation. Combined with the results from growth strata and magnetostratigraphy, we suggest that the segment presents a northwardly forward breaking pattern, with the deformation occurring along the Kedong belt during the early Pliocene, within the Kekeya belt at early-to mid-Pliocene and in the Guman-Heshitage belt during early-to mid-Pleistocene.%塔西南新生代前陆盆地受西昆仑山造山带南北向挤压和帕米尔弧形构造带向北突进的影响，导致盆山结构与盆地冲断带构造变形在平行造山带方向表现出明显差异。本文通过地震资料解释，系统研究了塔西南新生代前陆盆地东段盆山结构与冲断带的构造变形特征，认为塔西南新生代前陆盆地东段盆山结构表现为西昆仑造山带向北大规模冲断，盆地区挠曲沉降，前陆地区发育宽的褶皱冲断带，冲断带前锋已扩展至捷得背斜一线，褶皱冲断带与前渊坳陷存在大范围重叠。盆地东段的褶皱冲断带在纵向上可以分为基底卷入变形带、滑脱变形带。山前第一排变形带受多期构造叠加影响，产生横向变形的分异：西段柯东段早期为构造楔形体变形形成的背斜构造，后期被甫沙–克里阳右行走滑断裂改造，剖面呈现复杂的变形特征；东段克里阳段构造变形以早期的逆冲推覆为主。结合生长地层与磁性地层分析，冲断带的变形总体表现出前展式的构造变形特征，上新世阿图什组沉积期开始形成柯东构造带；随后变形向北传播，在上新世早中期形成柯克亚构造带；至早中更新世晚期，构造变形扩展至固满–合什塔格构造带。
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