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[Display omitted] • The Shillong plateau in northeast India records Archean/Proterozoic to Cenozoic histories. • Shillong group of rocks present as a supracrustal unit within the plateau which preserves multiple deformation events. • Microstructural investigations on shear zone rocks suggest a deformation sequence for the study area. • Kinematic and vorticity analyses indicate the transpressive nature of the Barapani Shear Zone (BSZ). • The BSZ is represented here as an intraterrane shear zone that is restricted within the plateau only. The analysis of shear zone kinematics plays a crucial role in understanding the tectonics at micro-, meso-, and regional scales within a given terrane. This study focuses on investigating the kinematics of prominent asymmetric structural features preserved within the Barapani Shear Zone (BSZ). These features are utilized to establish vorticity numbers in relation to the reference frames of the BSZ. Typically, shear zones provide finite values for kinematics and vorticity numbers. The BSZ is identified as an intraterrane, multiply deformed shear zone within the Shillong Plateau, which exhibits varying kinematics and vorticity numbers measured across different deformation zones. The research reveals that the BSZ underwent successive D 1 , D 2 , D 3 , and D 4 events, resulting in preserved S 1 , S 2 , and S 3 planar fabrics, with D 4 evidenced by brittle deformation features. However, determining shear zone kinematics purely based on the orientation of these planar fabrics and mineral lineation with respect to the external reference frame is insufficient. Consequently, this study calculates vorticity numbers and kinematics by considering both the external and internal reference frames of the BSZ. The study suggests that superposed transpressional tectonics prevailed during D 2 and D 3 events. [ABSTRACT FROM AUTHOR]

[Display omitted] • The far-field effects of the Indian-Asian collision and the crust-mantle processes triggered by the paleo-Pacific plate formed the Weihe Graben in the Paleogene. • The eastward extrusion of the Tibetan Plateau controls the evolution of the Weihe Graben since the Neogene. • The Weihe Graben was formed by a strike-slip and extensional combined mechanism in the Paleogene, but an extensional mechanism since the Neogene. The Weihe Graben is located in the composite area of the Tethys-Himalayan tectonic and circum-pacific tectonic domains and is an essential structural feature related to Cenozoic intracontinental deformation. However, two different hypotheses, sinistral strike-slip, and extensional mechanism, are proposed for the origin of this graben. In this study, we designed crust-scale analog models based on fault kinematics to better understand the deformation and dynamic mechanisms of the Weihe Graben. Fault kinematics shows early sinistral strike-slip and NW-SE extensional deformation and late NE-SW, S-N, and NW-SE extensional deformation. Our experimental results reveal that Model C1 (sinistral strike-slip + NW-SE extension) is the most similar to the geological structure of the Weihe Graben in the Paleogene. Furthermore, the NE-SW extension results in two larger subsidence areas in the northeast and southwest of the basin, similar to the formation of the two depressions during the Miocene. The S-N extension causes the basin to expand southward and northward, consistent with the sedimentary characteristics of Weihe Graben in the Pliocene. The NW-SE extension leads to relatively strong fault activity in the northwest and southeast of the basin, resembling the active fault characteristics since the Quaternary. Therefore, we propose that the Weihe Graben formed by a strike-slip and extensional combined mechanism in the Eocene-Oligocene, influenced by the far-field effects of the Indian-Asian collision and crust-mantle processes triggered by the stagnant paleo-Pacific plate. Subsequently, during the Neogene-Quaternary, the graben's development shifted towards an extensional regime under the influence of the eastward extrusion of the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

• The drainage systems and mountain ridges have been systematically left-lateral deflected or offset along the MTF. • Two morphogenic earthquakes occurred close to or slightly earlier than 9.41 ± 0.94 ky BP and after ∼1540 yr BP. • The MTF is a Holocene active fault. The Motuo Fault zone (MTF), the southeast boundary of the eastern Himalaya syntaxis, is an important information carrier to understand the present-day kinematics and geodynamics of the Tibetan Plateau. However, little knowledge has been obtained about its Holocene activity and structural features of the MTF due to the ubiquitous vegetation covering. Interpretations of satellite imageries, outcrop and trench observations, together with the radiocarbon and Optically Stimulated Luminescence (OSL) dating results reveal that (1) the MTF consists of multiple NE–SW-trending branch faults, forming a wide fault system that could be generally divided into the western segment, central segment and eastern segment; (2) the drainage systems, mountain ridges and alluvial fans have been systematically left-laterally deflected or offset along the MTF; (3) two surface-rupturing earthquakes occurred close to or slightly earlier than 9.41 ± 0.94 ky BP and after ∼1540 yr BP, respectively, indicating that the MTF is an Holocene active fault. Due to the very limited exposure, it is quite possible that many paleoseismic events have not been revealed by this study and previous publications. For a better understanding and assessment of the seismogenic behavior of the MTF, a complete paleoseismic sequence and reasonable earthquake recurrence model need to be set up, especially considering the complex geometry of the fault system that probably suggests intricate fault rupturing. [ABSTRACT FROM AUTHOR]

• K-Ar illite fault-gouge ages constrain the timing of the Wadi Kabir Fault at the Oman continental margin. • Fault-gouge ages of ∼95–85 Ma relate to contractional deformation and emplacement of the iconic Samail Ophiolite. • The age of 57.9 ± 2.0 Ma age corresponds with pronounced footwall cooling during the formation of the Bandar Jissah Basin. The complex structural geometry along the northern continental margin of Oman formed during polyphase deformation from the mid-Cretaceous to the Miocene. We focus on the kinematics and tectonics of the Wadi Kabir Fault, which represents an eastern segment of the large-scale, composite Frontal Range fault system that forms the northern boundary of the central Al Hajar Mountains. The most exhumed rocks outcrop in the Saih Hatat window of the Al Hajar Mountains, which occurs in the footwall of the Wadi Kabir Fault. To better understand the tectonic history of the Wadi Kabir Fault, we report three K-Ar illite fault-gouge ages. Sample FG16-1 from a shallowly north-dipping gouge zone of the eastern segment of the Wadi Kabir Fault yielded two consistent ages that overlap within 2σ uncertainties at ∼90 Ma. Sample FG16-2 from the central segment of the fault yielded a K–Ar age of 57.9 ± 2.0 Ma (2σ uncertainties), which is interpreted as a late Paleocene faulting event as it perfectly matches the cooling history of the high-pressure rocks of the Saih Hatat window in the footwall of the Wadi Kabir Fault. We present two tectonic interpretations for the ∼90 Ma fault-gouge age and prefer a synchronous kinematic relationship with the parallel and contractional mid-Cretaceous Yenkit Shear Zone that was active at the distal Arabian Platform since 114 Ma. Because the 57.9 ± 2.0 Ma age is associated with pronounced footwall cooling, we interpret this age to be related to the formation of the Bandar Jissah Basin in the hanging wall of the Wadi Kabir Fault. We conclude that the Frontal Range fault system likely formed during the Paleocene and that its young (≤∼43 Ma) history was accommodated along the western segment of the fault, as there is no evidence of this Eocene fault interval at the Wadi Kabir Fault. [ABSTRACT FROM AUTHOR]