The Kohat fold and thrust belt in Pakistan shows a significantly different structural style due to the structural evolution on the double décollement compared to the rest of the Subhimalaya. In order to better understand the spatio-temporal structural evolution of the Kohat fold and thrust belt, we combine balanced cross sections with apatite (U–Th-Sm)/He (AHe) and apatite fission track (AFT) dating. The AHe and AFT ages appear to be totally reset, allowing us to date exhumation above structural ramps. The results suggest that deformation began on the frontal Surghar thrust at ~15 Ma, predating or coeval with the development of the Main Boundary thrust at ~12 Ma. Deformation propagated southward from the Main Boundary thrust on double décollements between 10 Ma and 2 Ma, resulting in a disharmonic structural style inside the Kohat fold and thrust belt. Thermal modeling of the thermochronologic data suggest that samples inside Kohat fold and thrust belt experienced cooling due to formation of the duplexes; this deformation facilitated tectonic thickening of the wedge and erosion of the Miocene to Pliocene foreland strata. The spatial distribution of AHe and AFT ages in combination with the structural forward model suggest that, in the Kohat fold and thrust belt, the wedge deformed in-sequence as a supercritical wedge (~15-12 Ma), then readjusted by out-sequence deformation (~12-0 Ma) within the Kohat fold and thrust belt into a sub-critical wedge.

巴基斯坦的科哈特褶皱和逆冲带显示出明显不同的结构样式，这是因为与苏北喜马拉雅山的其余部分相比，双重折断构造上的构造演化。为了更好地了解Kohat褶皱和逆冲带的时空结构演化，我们将平衡截面与磷灰石（U–Th-Sm）/ He（AHe）和磷灰石裂变径迹（AFT）测年相结合。AHe和AFT的年龄似乎已被完全重置，这使我们能够确定挖掘出的结构坡道以上的尸体。结果表明，变形始于约15 Ma的额叶Surghar推力，早于或等效于约12 Ma的主边界推力的发展。变形从主边界推力向南传播到10 Ma至2 Ma之间的双重断层，导致Kohat褶皱和逆冲带内部构造不和谐。热年代学数据的热模型表明，由于双体的形成，科哈特褶皱和逆冲带内部的样品经历了冷却。这种变形促进了楔形的构造增厚和中新世至上新世前陆地层的侵蚀。AHe和AFT年龄的空间分布与结构前向模型相结合表明，在Kohat褶皱和逆冲带中，楔形物按顺序变形为超临界楔形物（〜15-12 Ma），然后按出序顺序重新调整褶皱和逆冲带中的变形（〜12-0 Ma）成亚临界楔形。这种变形促进了楔形的构造增厚和中新世至上新世前陆地层的侵蚀。AHe和AFT年龄的空间分布与结构前向模型相结合表明，在Kohat褶皱和逆冲带中，楔形物按顺序变形为超临界楔形物（〜15-12 Ma），然后按出序顺序重新调整褶皱和逆冲带中的变形（〜12-0 Ma）成亚临界楔形。这种变形促进了楔形的构造增厚和中新世至上新世前陆地层的侵蚀。AHe和AFT年龄的空间分布与结构前向模型相结合表明，在Kohat褶皱和逆冲带中，楔形物按顺序变形为超临界楔形物（〜15-12 Ma），然后按出序顺序重新调整褶皱和逆冲带中的变形（〜12-0 Ma）成亚临界楔形。