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The Xiongpo fault-fold belt shows prominent NE, ENE- and ~N–S-trending relief, which resulted from multi-stage upper crustal shortening in the Longmen Shan piedmont during the eastward growth of the eastern Tibetan Plateau. Previous studies have determined its 2D structural configurations from seismic profiles and field-based geological cross-sections. Here, we extend this analysis into the entire belt to explore the 3D structural evolution of this complex fault-fold belt and have built a 3D regional fault model. The results reveal along-strike variation of subsurface structural architecture of the Xiongpo fault-fold belt, which is characterized by transformation from a complex superimposition of a deep fault-bend fold beneath a shallow structural wedge in the center segment to a simple shallow fault-bend fold on both ends of the structure, and then to a trishear fault propagation fold on the plunging edges. This structural transformation determines the contrast between the NE-striking relief of the central segment, and the ENE- and ~N-S-striking relief in the two plunging zones. We combine our results with published low-temperature thermochronology and growth strata results to propose a three-stage evolution for the Xiongpo fault-fold belt that closely relates with regional stress field changes, including a NE-striking fault under the NW–SE compression between 40–25 Ma and 15–10 Ma, lateral propagation of the NE-striking fault and initiation of ENE-striking fault by WNW–ESE compression from ~5–2 Ma, ~N–S fault under ~E–W compression until the present. This work enhances our understanding of the stress field changes of eastern Tibet since the Late Eocene. It also can serve as a typical case study deciphering 3D fault-fold growth using seismic and geological imaging, which is helpful to understand 3D structural and landscape evolutions of other complex fault-fold belts worldwide.

The East Kunlun Shan (EKLS) in northern Tibet occupies boundaries of the low‐relief topography and lower crustal low‐velocity zone in the interior plateau, making it ideal for exploring the relationship of surface deformation with underlying geodynamic processes. We used previous and new apatite (U‐Th)/He data to analyze the exhumation history and pattern throughout the EKLS and link surface deformation to deep structures. Integrated (U‐Th)/He ages reveal the rapid exhumation at 27–25 Ma, due to the coeval orogen‐scale tilting of the EKLS. Along with the crustal structures beneath the EKLS, it is inferred that orogen‐scale tilting is the isostatic response of the nonuniform crustal thickening related to northward injection of the Tibetan lower crust. This study highlights the role of ductile deformation within the lower crust in mountain building in northern Tibet, which shares a similarity with mountain building pattern in the eastern plateau margin. Plain Language Summary How deep geodynamic process affects shallow crustal deformation in Tibet is one of the key issues in understanding continental dynamics. The East Kunlun Shan (EKLS) defines northern boundaries of low‐relief topography and crustal low‐velocity zone in the interior plateau. In this study, we explore the relationship between surface deformation and underlying geodynamic processes in the EKLS by analyzing the shallow crustal exhumation pattern in conjunction with deep structures. Amounts of apatite (U‐Th)/He ages across the EKLS reveal the late Oligocene orogen‐scale tilting, indicating the involvement of indistinctive shallow crustal shortening in the mountain building process. Such a regional tilting may be the reflection of nonuniform crustal thickening related to the injection of the Tibetan lower crust when considering the crustal structures beneath the EKLS. By comparing the mountain building patterns in the northern and eastern margins of Tibet, we conclude that ductile deformation in the lower crust may be a common phenomenon to mountain building in plateau margins. Key Points Apatite (U‐Th)/He data reveal the accelerated exhumation at 27‐25 Ma and southward increasing exhumation across the East Kunlun Shan (EKLS) The EKLS has experienced the orogen‐scale tilting during the late Oligocene Orogen‐scale tilting of the EKLS may be the isostatic response of northward injection of the Tibetan weak lower crust

The Yanshan movement/orogeny has been proposed for 90 years, which is of special significance in the history of geological research in China. This study conducted a review by synthesizing major achievements regarding episodic deformation features, sedimentary and magmatic records of the Yanshan orogeny in China, and clarified the episodic tectono-magmatism and its geodynamic origins. The tectonic implications of the Yanshan orogeny are discussed in the context of global plate tectonics and supercontinent reconstruction. Lines of evidence from structural, sedimentary and magmatic data suggest that the Yanshan orogeny represents a regional-scale tectonic event that affected the entire China continent in late Mesozoic period. Numerous age and structural constraints consistently indicate that the Yanshan orogeny was initiated in the Jurassic (at ∼170±5 Ma). and was characterized by alternating stages of crustal shortening at ∼170–136 Ma, crustal extension at ∼135–90 Ma, and weak shortening at ∼80 Ma. The 170–136 Ma crustal shortening was reflected in the generation of two regional stratigraphic unconformities (the Tiaojishan and Zhangjiakou unconformities), which were initially named the A and B episodes of “the Yanshan Orogeny” by Mr. Wong Wenhao in 1928. Geodynamically, the Yanshan orogeny in East Asia was associated with nearly coeval oceanic subduction and continental convergence in the Paleo-Pacific, Neo-Tethys, and Mongol-Okhotsk tectonic domains. As a consequence, three giant accretionary-collisional tectonic systems were formed along the continental margins of East Asia, i.e., the Mongol-Okhotsk, Bangonghu-Nujiang, and SE China subduction- and collision-related accretionary systems. The Yanshan orogeny induced widespread crustal-scale folding and thrusting, tectonic reactivation of long-lived zones of crustal weakness, and extensive magmatism and mineralization in intraplate regions. Based on the time principle of supercontinent assembly and break-up, we propose that the mid-Late Jurassic multi-plate convergence in East Asia might represent the initiation of the assembly of the Amasia supercontinent, and the Yanshan orogeny might be the first “stirrings” that is a prerequisite for the birth of the Amasia supercontinent.

The surface uplift of mountain belts is generally assumed to reflect progressive shortening and crustal thickening, leading to their gradual rise. Recent studies of the Andes indicate that their elevation remained relatively stable for long periods (tens of millions of years), separated by rapid (1 to 4 million years) changes of 1.5 kilometers or more. Periodic punctuated surface uplift of mountain belts probably reflects the rapid removal of unstable, dense lower lithosphere after long-term thickening of the crust and lithospheric mantle.

Cenozoic convergence between the Indian and Asian plates produced the archetypical continental collision zone comprising the Himalaya mountain belt and the Tibetan Plateau. How and where India–Asia convergence was accommodated after collision at or before 52 Ma remains a long-standing controversy. Since 52 Ma, the two plates have converged up to 3,600 ± 35 km, yet the upper crustal shortening documented from the geological record of Asia and the Himalaya is up to approximately 2,350-km less. Here we show that the discrepancy between the convergence and the shortening can be explained by subduction of highly extended continental and oceanic Indian lithosphere within the Himalaya between approximately 50 and 25 Ma. Paleomagnetic data show that this extended continental and oceanic \"Greater India\" promontory resulted from 2,675 ± 700 km of North–South extension between 120 and 70 Ma, accommodated between the Tibetan Himalaya and cratonic India. We suggest that the approximately 50 Ma \"India\"–Asia collision was a collision of a Tibetan-Himalayan microcontinent with Asia, followed by subduction of the largely oceanic Greater India Basin along a subduction zone at the location of the Greater Himalaya. The \"hard\" India–Asia collision with thicker and contiguous Indian continental lithosphere occurred around 25–20 Ma. This hard collision is coincident with far-field deformation in central Asia and rapid exhumation of Greater Himalaya crystalline rocks, and may be linked to intensification of the Asian monsoon system. This two-stage collision between India and Asia is also reflected in the deep mantle remnants of subduction imaged with seismic tomography.

We explore the connections between crustal shortening, volcanism, and mantle dynamics in the Atlas of Morocco. In response to compressional forces and strain localization, this intraplate orogen has evolved far from convergent plate margins. Convective effects, such as lithospheric weakening and plume‐related volcanism, contributed in important ways to the building of high topography. We seek to better understand how crustal and mantle processes interacted during the Atlas' orogeny by combining multiple strands of observations, including new and published data. Constraints on crustal and thermal evolution are combined with new analyses of topographic evolution, petrological, and geochemical data from the Anti‐Atlas volcanic fields, and a simple numerical model of the interactions among crustal deformation, a mantle plume, and volcanism. Our findings substantiate that: (a) crustal deformation and exhumation accelerated during the middle/late Miocene, contemporaneous with the onset of volcanism; (b) volcanism has an anorogenic signature with a deep source; (c) a dynamic mantle upwelling supports the high topography. We propose that a mantle plume and the related volcanism weakened the lithosphere beneath the Atlas and that this favored the localization of crustal shortening along pre‐existing structures during plate convergence. This convective‐tectonic sequence may represent a general mechanism for the modification of continental plates throughout the thermo‐chemical evolution of the supercontinental cycle. Key Points Crustal thickening is limited and cannot account for the topography elevation of the Atlas system Resumption of volcanism is contemporaneous with the acceleration of crustal deformation and topography growing The erosion and weakening of the lower lithosphere, as a consequence of mantle plume, may enhance crustal deformation and exhumation

A short step to an earthquake The Longmen Shan mountain range, which defines the eastern margin of the Himalayas, exhibits greater topographic relief than anywhere else in the Tibetan plateau. It was the site of the devastating 2008 Wenchuan magnitude-7.9 earthquake. Prior to the earthquake, geodetic and geologic surveys measured little shortening across the range front, prompting vigorous debate about the forces producing the topography of this mountain belt. Now Judith Hubbard and John Shaw present evidence from balanced geologic cross-sections that suggests that crustal shortening is a primary driver for uplift of the Longmen Shan and the Tibetan plateau, and that the 2008 Wenchuan earthquake was a product of this shortening process. This paper presents balanced geologic cross-sections showing that crustal shortening, structural relief and topography are strongly correlated in the Longmen Shan mountain range front, suggesting that crustal shortening is a primary driver for uplift and topography of the Longmen Shan on the flanks of the Tibetan plateau. The authors conclude that the 2008 Wenchuan earthquake is an active manifestation of this shortening process. The Longmen Shan mountain range, site of the devastating 12 May 2008 Wenchuan ( M =  7.9) earthquake, defines the eastern margin of the Himalayan orogen and exhibits greater topographic relief than anywhere else in the Tibetan plateau. However, before the earthquake, geodetic and geologic surveys measured little shortening across the range front 1 , 2 , 3 , inspiring a vigorous debate about the process by which the topography of the mountain belt is produced and maintained. Two endmember models have been proposed: (1) brittle crustal thickening, in which thrust faults with large amounts of slip that are rooted in the lithosphere cause uplift 4 , and (2) crustal flow, in which low-viscosity material in the lower crust extrudes outward from the Tibetan plateau and inflates the crust north and east of the Himalayas 5 , 6 , 7 . Here we use balanced geologic cross-sections to show that crustal shortening, structural relief, and topography are strongly correlated in the range front. This suggests that crustal shortening is a primary driver for uplift and topography of the Longmen Shan on the flanks of the plateau. The 2008 Wenchuan ( M =  7.9) earthquake, which ruptured a large thrust fault along the range front causing tens of thousands of fatalities and widespread damage, is an active manifestation of this shortening process.

Defining the structural style of fold–thrust belts and understanding the controlling factors are necessary steps towards prediction of their long-term and short-term dynamics, including seismic hazard, and to assess their potential in terms of hydrocarbon exploration. While the thin-skinned structural style has long been a fashionable view for outer parts of orogens worldwide, a wealth of new geological and geophysical studies has pointed out that a description in terms of thick-skinned deformation is, in many cases, more appropriate. This paper aims at providing a review of what we know about basement-involved shortening in foreland fold–thrust belts on the basis of the examination of selected Cenozoic orogens. After describing how structural interpretations of fold–thrust belts have evolved through time, this paper addresses how and the extent to which basement tectonics influence their geometry and their kinematics, and emphasizes the key control exerted by lithosphere rheology, including structural and thermal inheritance, and local/regional boundary conditions on the occurrence of thick-skinned tectonics in the outer parts of orogens.

Cordilleran orogenic systems, such as the modern Andes, are long belts of deformation and magmatism that are associated with the subduction of oceanic plates beneath continental ones. Although the oceanic plates have been thought to control the evolution of such systems, a number of processes operating in the upper continental plates have not been fully accounted for. The western American Cordilleras, for example, display a 25–50 million year (Myr) cycle of linked upper-plate processes. In a typical cycle, as the two plates converge and a magmatic arc forms, most of the continental crust shortens by thrusting behind the arc, whereas the lowermost continental lithosphere is shoved beneath the arc — a process that fuels episodic high-flux magmatism in the arc and simultaneously generates dense melt residues. On reaching a critical mass, these residues sink into the mantle, creating space beneath the arc and setting the stage for renewal of the cycle. This alternative model explains key features of Cordilleran systems, such as cyclical trends in the flux and composition of magma supplied to the upper plate, and the foundering of arc roots. Cordilleran orogenic systems are long belts of deformation and magmatism that form when oceanic plates subduct beneath continental ones. Links between processes in the upper continental plate explain key features of Cordilleran systems, such as cyclical trends in the flux and composition of magma supplied to the upper plate.

Central and western Europe were affected by a compressional tectonic event in the Late Cretaceous, caused by the convergence of Iberia and Europe. Basement uplifts, inverted graben structures, and newly formed marginal troughs are the main expressions of crustal shortening. Although the maximum activity occurred during a short period of time between 90 and 75 Ma, the exact timing of this event is still unclear. Dating of the start and end of Late Cretaceous basin inversion gives very different results depending on the method applied. On the basis of borehole data, facies, and thickness maps, the timing of basin reorganization was reconstructed for several basins in central Europe. The obtained data point to a synchronous start of basin inversion at 95 Ma (Cenomanian), 5 Myr earlier than commonly assumed. The end of the Late Cretaceous compressional event is difficult to pinpoint in central Europe, because regional uplift and salt migration disturb the signal of shifting marginal troughs. Late Campanian to Paleogene strata deposited unconformably on inverted structures indicate slowly declining uplift rates during the latest Cretaceous. The differentiation of separate Paleogene inversion phases in central Europe does not appear possible at present.