<p>Continental tectonics is characterized by a mosaic of relatively young mobile belts surrounding ancient cratonic cores. The formation and evolution of such mobile belts have remained a hotspot and frontier in the study of continental geology since the establishment of plate tectonics theory. While the traditional plate tectonics confines the orogenic activity to subduction and collision processes at plate margins, numerous orogens also occur in continental interiors far from active plate boundaries. This article presents a systematic analysis of geological records from globally representative intracontinental orogen and integrates multidimensional evidence chains from tectonics, metamorphism, and magmatism, aiming to establish the causative mechanisms and product characteristics of intracontinental orogeny. Our results reveal three key aspects of intracontinental orogeny: (1) independence and universality as a distinct tectonic type independent of active plate boundaries; (2) the control of continental lithospheric heterogeneity, where continental weak zones—possessing greater reactivation potential than rigid cratonic cores—are prerequisites for intracontinental orogenesis; (3) the dual dynamic mechanism involving either far-field compressional stress transmission from remote plate margins or near-field extensional stress focus from local plate bottom. Although all intracontinental orogens were produced by the reactivation of tectonic weak zones (fossil suture zones and rift zones), they manifest themselves in two ways. One is realized by far-field stresses from remote plate margins to cause fold-thrust deformation and crustal uplift, giving rise to intracontinental compression orogens. The other is achieved by near-field stresses from local underplating of asthenospheric upwelling consequential to lithospheric foundering, resulting in regional metamorphism at high geothermal gradients and felsic magmatism as well as detachment faulting and the extrusion of metamorphic core complexes to form intracontinental rift orogens. Based on global comparative studies, this article attempts to integrate regional models of intracontinental orogens into the theoretical framework of dual dynamic mechanisms and reconstruct their three-stage development from continental margin orogens through intracontinental weak zones to intracontinental orogens. Studies of typical cases indicate that the majority of intracontinental orogens experienced two-stage processes from subduction/collision orogenies at plate margins to intracontinental compression/rift orogenies, with some of them developing into a new stage of the intracontinental compressional orogeny through. This article dismantles the traditional paradigm of “mountain building = plate margin process”, demonstrating that the development of intracontinental orogens from past plate margins is a common phase in continental tectonics and thus can be generalized by a tectonic model for intracontinental reworking of plate margins. It is one of key steps in continental assembly-breakup cycles and hence a necessary process between continental collision and seafloor spreading, thus serving as a prelude to supercontinent breakup. Recognition of the dual dynamic mechanisms for intracontinental orogeny provides new insights into the occurrence of mineral resources, fossil energy and earthquake hazards in continental interiors, as well as the stability of cratonic lithospheres, representing a critical step toward advancing the paradigm shift from the plate tectonics theory to the continental dynamics.</p>

Origin and genesis of intracontinental orogens

期刊论文
发表日期：

2025年11月11日

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Yu Wang,
Yongfei Zheng

摘要

Continental tectonics is characterized by a mosaic of relatively young mobile belts surrounding ancient cratonic cores. The formation and evolution of such mobile belts have remained a hotspot and frontier in the study of continental geology since the establishment of plate tectonics theory. While the traditional plate tectonics confines the orogenic activity to subduction and collision processes at plate margins, numerous orogens also occur in continental interiors far from active plate boundaries. This article presents a systematic analysis of geological records from globally representative intracontinental orogen and integrates multidimensional evidence chains from tectonics, metamorphism, and magmatism, aiming to establish the causative mechanisms and product characteristics of intracontinental orogeny. Our results reveal three key aspects of intracontinental orogeny: (1) independence and universality as a distinct tectonic type independent of active plate boundaries; (2) the control of continental lithospheric heterogeneity, where continental weak zones—possessing greater reactivation potential than rigid cratonic cores—are prerequisites for intracontinental orogenesis; (3) the dual dynamic mechanism involving either far-field compressional stress transmission from remote plate margins or near-field extensional stress focus from local plate bottom. Although all intracontinental orogens were produced by the reactivation of tectonic weak zones (fossil suture zones and rift zones), they manifest themselves in two ways. One is realized by far-field stresses from remote plate margins to cause fold-thrust deformation and crustal uplift, giving rise to intracontinental compression orogens. The other is achieved by near-field stresses from local underplating of asthenospheric upwelling consequential to lithospheric foundering, resulting in regional metamorphism at high geothermal gradients and felsic magmatism as well as detachment faulting and the extrusion of metamorphic core complexes to form intracontinental rift orogens. Based on global comparative studies, this article attempts to integrate regional models of intracontinental orogens into the theoretical framework of dual dynamic mechanisms and reconstruct their three-stage development from continental margin orogens through intracontinental weak zones to intracontinental orogens. Studies of typical cases indicate that the majority of intracontinental orogens experienced two-stage processes from subduction/collision orogenies at plate margins to intracontinental compression/rift orogenies, with some of them developing into a new stage of the intracontinental compressional orogeny through. This article dismantles the traditional paradigm of “mountain building = plate margin process”, demonstrating that the development of intracontinental orogens from past plate margins is a common phase in continental tectonics and thus can be generalized by a tectonic model for intracontinental reworking of plate margins. It is one of key steps in continental assembly-breakup cycles and hence a necessary process between continental collision and seafloor spreading, thus serving as a prelude to supercontinent breakup. Recognition of the dual dynamic mechanisms for intracontinental orogeny provides new insights into the occurrence of mineral resources, fossil energy and earthquake hazards in continental interiors, as well as the stability of cratonic lithospheres, representing a critical step toward advancing the paradigm shift from the plate tectonics theory to the continental dynamics.