ABSTRACT The complex tectonic evolution of the western Ordos Basin (WOB) has long been considered to be responsible for the distinctive tectonic‐geomorphic framework within this tectonic belt. The Weiningbeishan Tectonic Belt (WTB), located at the junction of multiple tectonic units in the central segment of the WOB, constitutes a key region for investigating intracontinental tectonic evolution. Combined with regional geology, the present study employed low‐temperature thermochronology to comprehensively constrain the Mesozoic‐Cenozoic uplift and exhumation history of the WTB. The obtained apatite fission track ages range from 120.6 ± 4.7 to 147.1 ± 8.0 Ma, representing a significant cooling event from the Late Jurassic to Early Cretaceous. Combined with thermal history modelling, we further reveal four major cooling‐uplift events since the Mesozoic: the Late Triassic, Late Jurassic, Palaeocene‐Eocene and Miocene. These multi‐phase events are well recorded in the geological data of the WTB and adjacent regions. Furthermore, this study has further compiled existing low‐temperature thermochronological data of the WOB and conducted a systematic comparison of the characteristics and dynamic settings of these tectonic events. The results indicate that: (1) the Late Triassic tectonic event is most prominent in the southern segment with a northward propagation trend, linked to the collision and amalgamation of the North China Block (NCB) and South China Block (SCB); (2) the Late Jurassic tectonic event is associated with multi‐directional compression on the Ordos Basin (OB), evidenced by widespread low‐temperature thermochronological records; (3) the Late Cretaceous tectonic event is characterised by regional slow uplift, related to deep geodynamic changes beneath the NCB; (4) the Eocene tectonic event is correlated with regional extension, corresponding to the distribution of contemporaneous faulted basins; and (5) the Late Miocene tectonic event also demonstrates stronger deformation in the south, related to the outward expansion of the northeastern Tibetan Plateau. Therefore, the Mesozoic‐Cenozoic tectonic evolution of the WOB has been controlled by the superimposed and fluctuating influences of multiple adjacent tectonic units, ultimately resulting in the complex and diverse tectonic‐geomorphic patterns across its various segments.
Zhao et al. (Sun,) studied this question.