The Tajik basin and southwestern Tian Shan constitute the northwestern tip of the India-Asia collision zone. Basin inversion formed the thinskinned Tajik fold-thrust belt, outlined by westward convex fold trains, underlain by a decollement in Jurassic evaporites. The belt's leading edge-the Uzbek Gissar-and its transpressional northern lateral margin-the Tajik Gissar-constitute the thickskinned foreland buttresses. Apatite fission-track data indicate~40-to 15-Ma reheating by sediment burial in the Tian Shan. In the Gissar and the Tajik fold-thrust belt, apatite fission-track and (U,Th)/He ages date the major phase of shortening/erosion between~12 and 1 Ma, with exhumation to 2-to 3-km crustal depths within a few Myr after onset of shortening. Shortening spread immediately across the fold-thrust belt, typical for belts floored by a detachment in ductile rocks, and into the foreland buttresses. Reactivation concentrated in the internal (eastern) fold-thrust belt with the thickest evaporates. The youngest ages (~6.6-1.6 Ma) occur along the Vakhsh thrust, the active erosional front of the fold-thrust belt in the northeastern Tajik basin, where it narrows between the converging Tian Shan and Pamir. Our study links major events in the Pamir hinterland with the Tajik basin and Tian Shan foreland. In the late Eocene-early Miocene, the advancing Pamir-plateau crust loaded the foreland, inducing subsidence, reheating, and early shortening. Basin inversion and major shortening/transpression in the foreland buttresses from~12 Ma onward were synchronous with the subcrustal indentation of Indian lithosphere into the Tajik-Tarim basin lithosphere and the onset of its rollback beneath the Pamir.

中文翻译：

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塔吉克盆地与西南天山、西北印亚碰撞带：2. 盆地反转时间、天山构造与帕米尔高原推进和印亚深部压痕的关系

塔吉克盆地和西南天山构成印亚碰撞带的西北端。盆地反转形成了薄皮的塔吉克褶皱逆冲冲断带，由向西凸出的褶皱列勾勒出轮廓，下方是侏罗纪蒸发岩中的脱层。带的前缘——乌兹别克吉萨尔——及其横压北侧缘——塔吉克吉萨尔——构成了厚皮的前陆扶壁。磷灰石裂变径迹数据表明天山沉积物埋藏约 40 至 15 Ma 再加热。在 Gissar 和 Tajik 褶皱冲断带，磷灰石裂变径迹和 (U,Th)/He 年龄确定了约 12 至 1 Ma 之间缩短/侵蚀的主要阶段，并折返至 2 至 3 公里地壳深度在缩短开始后的几个 Myr 内。起酥油立即在折叠推力带上蔓延，典型用于由韧性岩石中的分离层和进入前陆支撑的带。再活化集中在蒸发最厚的内部（东部）褶皱逆冲带。最年轻的年龄（~6.6-1.6 Ma）发生在瓦赫什逆冲断层，这是塔吉克盆地东北部褶皱冲断带的活跃侵蚀前沿，在汇聚的天山和帕米尔之间变窄。我们的研究将帕米尔腹地的重大事件与塔吉克盆地和天山前陆联系起来。在始新世晚期—中新世早期，推进的帕米尔高原地壳加载前陆，导致下沉、再加热和早期缩短。