Catálogo de publicaciones - revistas

<jats:p>No abstract is available for this article.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The Tieluzi Fault is the largest structure in the East Qinling Mountains, and is considered to be the easternmost continuation of the Altyn Tagh‐Haiyuan‐Qinling Fault System (AHQFS) that allows the eastward extrusion of the Tibetan Plateau and South China Block. We studied the fault geometry and kinematics of the Tieluzi Fault using field investigations, detailed interpretations of high‐resolution satellite imagery and digital elevation models, and late Quaternary dating methods. Paleoseismic investigations indicate that the most recent earthquake along the Tieluzi Fault occurred before 1,500–1,300 cal. BP. Geological and geomorphological observations show that segments west of Lushi County are more active than those to the east. The spatial variations in tectonic activity along the Tieluzi Fault are interpreted to be related to four possible mechanisms: strike change, discontinuity, intersection, and branch. The late Quaternary left‐lateral slip rate is determined to be 0.9 ± 0.1 mm/yr on the Tieluzi Fault. The prominent left‐lateral faulting along the Tieluzi Fault suggests that most of the left‐lateral displacement along the eastern AHQFS has been accommodated by the Tieluzi Fault, which forms the most frontier of the eastward expansion of the Tibetan Plateau. Furthermore, we suggest that the left‐lateral faulting in the East Qinling Mountains is a response to relative eastward motion of the South China block pushed by the Tibetan Plateau with respect to the North China Plain Block. Also, our results indicate that the Tibetan Plateau has undergone a stepwise eastward expansion.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Since the Mesozoic, eastern NE Asia has experienced multiple tectonic events, resulting in a complex structure and forming one of the world's largest Meso‐Cenozoic lacustrine basin systems. Presently, basin evolution models require further elucidation regarding the simultaneous generation of diverse rift basins and the potential impact stemming from the closure of the Mudanjiang Ocean, whose oceanic closure demarcated the boundary between the Songliao Basin and the eastern basins, raises questions about its influence on the development of the basin‐and‐range system. To address these questions, we augment new low‐temperature thermochronological data on basement highs separating the eastern NE Asia basins to investigate the shallow‐deep coupling process of tectonic evolution since the Mesozoic. The new cooling age pattern shows non‐overlapping and spatial differences among major basement highs. Inverse thermal modeling revealed five‐stage cooling episodes among the basement highs, but with different onset and cooling rates of each episode, indicating a significant differential uplift mode. A major reburial stage was identified throughout eastern NE Asia during the mid‐Cretaceous. Compiling cooling age patterns and inverse thermal modeling, we note the existence of a proto‐basin covering an area much larger than the previously contemplated “Pan‐Sanjiang” Basin. In general, our study indicates the final closure of the Mudanjiang Ocean occurred at ca. 150–140 Ma. Since the Early Cretaceous, with changes in the subduction direction, two‐stage flat slab subduction of the Paleo‐Pacific plate and the consequent subduction of the Pacific plate co‐dominated the basements' differential uplift and the formation of the eastern NE Asia basin‐and‐range framework.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The presence of pre‐existing fabrics at all lithospheric scales has been proven to be of primary importance in controlling the evolution of continental rifts. Indeed, observations from natural examples show that even in conditions of orthogonal rifting, when extension should result in simple fault patterns dominated by normal faults orthogonal to extension vectors, inherited fabrics induce complex arrangements of differently‐oriented extension‐related structures. This paper explored the influence of inherited fabrics on rift‐related structures by using a series of analog models deformed in a centrifuge. The models reproduced a brittle‐ductile crustal system and considered the presence of pre‐existing discrete fabrics in the brittle crust in conditions of orthogonal narrow rifting. These fabrics were reproduced by cutting the brittle layer at different orientations with respect to the extension direction. Modeling shows pre‐existing fabrics have a significant influence on rift‐related faults, provided that the angle between inherited fabrics and the rift trend is less than 45°. In these conditions, fabrics cause prominent segmentation of rift‐related faults and induce the development of isolated depocenters. Pre‐existing fabrics strongly influence the geometry of extension‐related structures, resulting in curved fault patterns and en‐echelon arrangement of oblique faults. These findings provide insights into the development of continental rift systems in nature: our modeling shows indeed significant similarities (i.e., peculiar fault architecture and geometries) with the faults in different sectors of the East African Rift System (e.g., the Magadi and Bogoria basin, Kenya Rift), testifying that reactivation of inherited fabrics is a paramount process in shaping continental rifts.</jats:p>

<jats:p>No abstract is available for this article.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Two main types of subduction are recognized around the world: accretionary and erosive. The northern Peruvian margin is a well‐known example of a margin subjected to subduction erosion, but to date the along‐margin variability and temporal changes in subduction process and forearc basin evolution have not been characterized in detail. Interpretation of regional seismic lines and integration of oil‐industry wells and seafloor data captures the erosive nature of subduction underneath the forearc with only a minor accretionary component to the north. Episodes of uplift driven by plate coupling were followed by normal faulting/extensional collapse due to plate decoupling. This mechanism explains the dominance of normal faulting across the forearc until the Oligocene with a slight reactivation within the Miocene. The subduction history is complex and includes a reduction in plate convergence rate related to forearc crustal shortening, represented by large‐scale structures including the Peru fault (reactivated) and the Illescas fault‐propagation anticlines of the Northwest Peru transpressional system. This crustal deformation started in the Miocene. Integration with magnetic anomaly data indicates that activity of the present‐day transpressional system driven by tectonic escape of the Nazca Sliver toward the northeast, may explain the seismicity gap in southern Ecuador and northern Peru. An evolutionary model of the northern Peruvian margin shows how subduction zone geodynamics left its erosive fingerprint in the forearc basin configuration.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The Southwestern Branch of the East African Rift System propagates through the Central and Southern African plateaus and ends in the Okavango Makgadikgadi Zambezi Basin. This basin hosts the Okavango Graben and the Eiseb Graben, considered as the terminus of the Southwestern Branch of the rift. To the southeast, the Makgadikgadi Basin is affected by a series of normal faults forming the Makgadikgadi Rift Zone (MRZ) which regional geodynamic significance remains unclear. Based on fieldwork and geomorphic analysis, we revisited the geomorphological features associated with paleolakes and the fault pattern within the Makgadikgadi Basin to better constrain the dynamics of the MRZ. Fault scarps and offsets along linear dunes show normal‐dip kinematics of faults, indicating a NW‐SE extension direction in the area. Furthermore, lacustrine shorelines in the basin are undeformed, proving that they post‐date the fault activity. The previously published ages of these shorelines demonstrate that the MRZ currently has a low tectonic activity. Integrated in the geodynamic framework of the region, these results suggest that present‐day deformation shifts toward the Okavango Graben north of the MRZ. We therefore propose a “zip‐opening” model to explain the propagation of the Southwestern Branch of the East African Rift System where the tip of the system progressively progresses southwestward, driven by motions of the continental plates.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Understanding the propagation of shortening, especially the interaction of shallow and deep structural levels in space and time is important to understand the accretion process of a compressional orogen as well as to fully understand earthquake hazards to populated foreland basins. Here we combine evidence from geologic maps and stream‐terrace surveys to construct a set of retrodeformable cross‐sections of the western North Qilian Shan foreland. The uplifted, severely tilted Mesozoic and older rock units suggest the presence of both deep and shallow décollements in western and central part of our research area, and that these structures alternated activity since commencement of the latest phase of the North Qilian Shan uplift. Conversely, in the east, the absence of foreland fold‐and‐thrust belt and the moderately tilted Mesozoic rocks indicate the deformation is dominated by thick‐skinned uplift. Based on our cross‐sections, we estimate the long‐term shortening rate of the Jiuxi foreland basin of 1.2–1.8 m/Kyr. Deformed foreland terraces show that, from west to east in our research area, active deformation switches between different structural levels. This trade‐off between deformation styles in time and space shows that two décollement levels bound a crustal‐scale duplex as the foreland is incorporated into the orogen. We suggest the complex and out‐of‐sequence deformation pattern may relate to pre‐existing weakness within the basement rocks and is likely a common characteristic of the North Qilian foreland. This may impose an additional challenge for seismic hazard estimation of the region.</jats:p>

<jats:p>No abstract is available for this article.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Vietnam contains complex faults coupled with a diffuse igneous province that has been active since the mid‐Miocene. However, existing fault maps demonstrate little consensus over the location of Neogene basalt flows and relative ages of mapped faults, which complicates interpretations of tectonic model for the evolution of Indochina. This paper identifies discrete tectonic blocks within Vietnam and aims to define the Neogene‐Recent tectonic setting and kinematics of south‐central Vietnam by analyzing the orientation, kinematics, and relative ages of faults across each block. Fault ages and relative timing are estimated using cross‐cutting relationships with dated basalt flows and between slickenside sets. Remote sensing results show distinct fault trends within individual blocks that are locally related to the orientations of the basement‐involved block‐bounding faults. Faults observed in the field indicate an early phase of dip‐slip motion and a later phase of strike‐slip motion, recording the rotation of blocks within a stress field. Faulting after the change in motion of the Red River Fault Zone at ∼16 Ma is inferred, as faults cross‐cut basalt flows as young as ∼0.6 Ma. Strike‐slip motion on block‐bounding faults is consistent with rotation and continuous extrusion of each block within south‐central Vietnam. The rotation of the blocks is attributed to the “continuum rubble” behavior of small crustal blocks influenced by upper mantle flow after the collision between India and Eurasia. We infer a robust lithospheric‐asthenospheric coupling in the extrusion model, which holds implications for other regions experiencing extrusion even in the absence of a free surface.</jats:p>