Abstract:The Zagros orogenic belt is one of the youngest orogenic belts in the world, but previous studies of its tectonic evolution history are still controversial. The foreland basin is rich in thermal history information, which provides an important way to explore the uplifting and exhumation history of the orogenic belt. In this study, we collected 11 coarse sandstone samples of the Kuh-E Bedush syncline and Kuh-E Murdeh syncline in the forefront of the middle Zagros foreland basin. A total of 38 single-grain ages were obtained by using apatite (U-Th)/He thermochronometry, which range from 79.9 Ma to 0.8 Ma. Single-grain age of most samples is relatively scattered, indicating that these samples did not undergo a complete thermal reset. In contrast, sample LS10 which located at the bottom of the Murdeh syncline has a (U-Th) / He age that is much younger than its corresponding stratigraphic age, and clusters at 8.3 ~ 6.8 Ma, indicating sample LS10 has been completely reset and recorded the last cooling event. Therefore, we believe that the Zagros foreland basin experienced a rapid exhumation event during the Late Miocene ~ 7.5 Ma. In addition, we found that the unreset AHe ages roughly distributed in four periods: Late Cretaceous-Early Paleozoic, Early-Middle Eocene, Oligocene, early-middle Miocene. Three different thermal histories were set based on the obtained He ages and previous studies, and the forward modeling results fit well with the actual samples. We suggest that the Agha Jari formation in the central foreland basin may source from: (1) continuous exhumation of obduction body mainly dominated by ophiolites since the late Cretaceous; (2) the Sanandaj-Sirjan metamorphic zone (SSZ) with gradual acceleration of cooling rate during the Oligocene and Miocene; (3) the syn-orogenic conglomerates accumulated above the thrusting body of High Zagros at the end of the Oligocene, then exhumed again during the Miocene thrusting period.