scholarly journals Structural Overview and Morphotectonic Evolution of a Strike-Slip Fault in the Zone of North Almora Thrust, Central Kumaun Himalaya, India

2016 ◽  
Vol 2016 ◽  
pp. 1-16 ◽  
Author(s):  
Lalit M. Joshi ◽  
Pitamber D. Pant ◽  
Bahadur S. Kotlia ◽  
Girish C. Kothyari ◽  
Khayingshing Luirei ◽  
...  
Keyword(s):  
Shear Zone ◽  
Strike Slip ◽  
Strike Slip Fault ◽  
Asymmetry Factor ◽  
Base Line ◽  
Gradient Index ◽  
River Channels ◽  
Fluvial Terraces ◽  
Dextral Strike Slip Fault ◽  
Dextral Strike Slip

The aim of the present research is to provide the base line details of the NNW-SSE trending Raintoli fault (RF) which is running parallel to the North Almora Thrust (NAT) along the Saryu valley from Seraghat-Naichun to Seri in the central sector of the Uttarakhand Himalaya, India. The RF is characterized as dextral strike slip fault and behaves as a ductile shear zone within the zone of NAT. The dextral sense of shear movement of RF is delineated by the fabric of the shear zone rocks including microscopically observed indicators such as sigma and delta porphyroclasts, quartz c-axis, and the field structural data. Additionally, in the quaternary period the dextral strike slip fault is reactivated with oblique slip component as characterized by various geomorphic indicators, for example, triangular facets, abandoned river channels, unpaired fluvial terraces, and V-shaped valleys with recurrent seismicity. Further, the morphometric parameters including Valley Floor Width to Valley Height (Vf), asymmetry factor (AF), and gradient index (GI) further prove active nature of RF as suggested by low values of hypsometric integration, V-shaped valley, higher gradient index, and tilting of Saryu basin.

scholarly journals Structural analysis of S-wave seismics around an urban sinkhole; evidence of enhanced subrosion in a strike-slip fault zone

2017 ◽  
Author(s):  
Sonja H. Wadas ◽  
David C. Tanner ◽  
Ulrich Polom ◽  
Charlotte M. Krawczyk
Keyword(s):  
Strike Slip ◽  
Strike Slip Fault ◽  
Key Factors ◽  
S Wave ◽  
Seismic Profiles ◽  
Reflection Seismic ◽  
Dextral Strike Slip Fault ◽  
Seismic Sections ◽  
The Town ◽  
Dextral Strike Slip

Abstract. In November 2010, a large sinkhole opened up in the urban area of Schmalkalden, Germany. To determine the key factors which benefited the development of this collapse structure and therefore the subrosion, we carried out several shear wave reflection seismic profiles around the sinkhole. In the seismic sections we see evidence of the Mesozoic tectonic movement, in the form of a NW–SE striking, dextral strike-slip fault, known as the Heßleser Fault, which faulted and fractured the subsurface below the town. The strike-slip faulting created a zone of small blocks (

scholarly journals First evidence of active transpressive surface faulting at the front of the eastern Southern Alps, northeastern Italy. Insight on the 1511 earthquake seismotectonics

2018 ◽  
Author(s):  
Emanuela Falcucci ◽  
Maria Eliana Poli ◽  
Fabrizio Galadini ◽  
Giancarlo Scardia ◽  
Giovanni Paiero ◽  
...  
Keyword(s):  
Strike Slip ◽  
Southern Alps ◽  
Strike Slip Fault ◽  
Fault System ◽  
The Past ◽  
Fold And Thrust Belt ◽  
Northeastern Italy ◽  
Dextral Strike Slip Fault ◽  
Seismic Lines ◽  
Dextral Strike Slip

Abstract. We investigated the eastern corner of northeastern Italy, where the NW-SE trending dextral strike-slip fault systems of western Slovenia intersects the south-verging fold and thrust belt of the eastern Southern Alps . The area suffered the largest earthquakes of the region, among which are the 1511 (Mw 6.3) event and the two major shocks of the 1976 seismic sequence, with Mw = 6.4 and 6.1 respectively. The Colle Villano thrust and the Borgo Faris-Cividale strike-slip fault have been first analyzed by interpreting industrial seismic lines and then by performing morpho-tectonic and paleoseismological analyses. These different datasets indicate that the two structures define an active, coherent transpressive fault system that activated twice in the past two millennia, with the last event occurring around the 15th–17th century. The chronological information, and the location of the investigated fault system suggest its activation during the 1511 earthquake.

scholarly journals Pull-apart basin tectonic model is structurally impossible for Kashmir basin, NW Himalaya

2016 ◽  
Author(s):  
A. A. Shah
Keyword(s):  
Strike Slip ◽  
Strike Slip Fault ◽  
Fault System ◽  
Nw Himalaya ◽  
Tectonic Model ◽  
Pull Apart Basin ◽  
Piggyback Basin ◽  
Kashmir Basin ◽  
Dextral Strike Slip Fault ◽  
Dextral Strike Slip

Abstract. Kashmir Basin in NW Himalaya is considered a Neogene-Quatermary piggyback basin that was formed as result of the continent-continent collision of Indian and Eurasian plates. This model however is recently challenged by a pull-apart basin model, which argues that a major dextral strike-slip fault through Kashmir basin is responsible for its formation. And here it is demonstrated that the new tectonic model is structurally problematic, and conflicts with the geomorphology, geology, and tectonic setting of Kashmir basin. It also conflicts, and contradicts with the various structural features associated with a typical dextral strike-slip fault system where it shows that such a major structure cannot pass through the middle of the basin. It is demonstrated that such a structure is structurally, and kinematically impossible, and could not exist.

scholarly journals Interpretasi Struktur Geologi Berdasarkan Fault Fracture Density (FFD) dan Implikasinya Terhadap Potensi Likuefaksi di Daerah Kalibening, Kabupaten Banjarnegara, Jawa Tengah

EKSPLORIUM ◽  
2021 ◽  
Vol 42 (1) ◽  
pp. 47
Author(s):  
Huzaely Latief Sunan ◽  
Akhmad Khahlil Gibran ◽  
Maulana Rizki Aditama ◽  
Sachrul Iswahyudi ◽  
Fajar Rizki Widiatmoko ◽  
...  
Keyword(s):  
Bouguer Anomaly ◽  
Shallow Groundwater ◽  
Geological Structure ◽  
Mapping Method ◽  
Strike Slip ◽  
Strike Slip Fault ◽  
Fracture Density ◽  
Geological Structures ◽  
Dextral Strike Slip Fault ◽  
Dextral Strike Slip

ABSTRAK Keberadaan struktur geologi sering dikaitkan dengan bencana tanah longsor dan gempa bumi. Daerah Kalibening merupakan lokasi yang cukup menarik untuk dilakukan penelitian terkait hal tersebut. Daerah ini tersusun atas satuan batuan berumur Pleistosen dan Resen. Berdasarkan stratigrafinya, batuan tersebut terpotong oleh struktur sesar. Hal ini berarti menjadikan sesar di daerah tersebut termasuk dalam kategori sesar aktif. Morfologi yang tinggi dengan suatu cekungan di tengahnya mengindikasikan bahwa daerah tersebut pembentukannya dipengaruhi oleh sesar. Penelitian ini bertujuan untuk menentukan pola struktur geologi yang mengontrol daerah penelitian. Untuk menentukan pola struktur geologi, digunakan metode pemetaan struktur Fault Fracture Density (FFD) yang dikombinasikan dengan peta residual anomali Bouguer dan peta kelurusan hillshade. Secara umum, hal yang paling penting dalam mempelajari struktur geologi adalah geometri elemen struktur. Model konseptual struktur geologi selanjutnya digunakan untuk menganalisis potensi likuefaksi yang ada pada daerah penelitian. Interpretasi struktur menunjukkan adanya sesar mendatar dekstral yang diikuti sesar-sesar penyerta dan cekungan pull-apart yang diduga merupakan hasil pensesaran normal yang timbul dari mekanisme strike-slip. Sesar mendatar dekstral ini menghasilkan cekungan yang terisi oleh sedimen lepas yang rentan mengalami likuefaksi jika terjadi gempa bumi dan gerakan tanah. Kajian ini menyimpulkan bahwa daerah Kalibening rentan terjadi likuefaksi karena adanya pergerakan sesar mendatar dekstral, sedimen lepas yang mendominasi daerah penelitian, dan muka air tanah yang dangkal. ABSTRACT The existence of geological structures is often associated with landslides and earthquakes. The Kalibening area is an interesting location for research on that purpose. This area is composed of Pleistocene and Recent rocks units. Based on its stratigraphy, the rocks in the area are truncated by fault structure. It means that the fault in the area is categorized as an active fault. The high morphology and a basin existence on its center indicate that the area formation was controlled by faults. The research is carried out to determine the trend of the geological structures that control the study area. To determine the trend of the geological structure, a structural mapping method of Fault Fracture Density (FFD) map combined with the Bouguer anomaly residual map and hillshade lineaments map is used. In general, the most important thing in the study of structural geology is the geometry of the structural elements. The conceptual model of geological structures is subsequently used to analyze the liquefaction potential of the study area. The interpretation of the structures shows the existence of dextral strike-slip fault followed by companion faults and pull-apart basin that is inferred as the result of normal faulting in the strike-slip mechanism. The dextral strike-slip fault produces a basin filled with loose sediment that is prone to liquefaction in the event of an earthquake and ground motion. This study concludes that the Kalibening area is prone to liquefaction due to the existence of the movement of dextral strike-slip fault, loose sediments that dominate the study area, and shallow groundwater table.

scholarly journals Is pull-apart basin tectonic model feasible for the formation of Kashmir basin, NW Himalaya

2017 ◽  
Vol 16 (1) ◽  
Author(s):  
Afroz Ahmad Shah ◽  
Mohammad Noor Firdhaus bin Yassin ◽  
Muhammad Izzat Izzuddin bin Haji Irwan
Keyword(s):  
Tectonic Setting ◽  
Strike Slip ◽  
Strike Slip Fault ◽  
Nw Himalaya ◽  
Tectonic Model ◽  
Pull Apart Basin ◽  
Piggyback Basin ◽  
Kashmir Basin ◽  
Dextral Strike Slip Fault ◽  
Dextral Strike Slip

Kashmir Basin in NW Himalaya is considered a Neogene-Quatermary piggyback basin that was formed as result of the continent-continent collision of Indian and Eurasian plates. This model however is recently challenged by a pull-apart basin model, which argues that a major dextral strike-slip fault that runs through the Kashmir basin is responsible for its formation. And here it is demonstrated that this tectonic model is structurally unrealistic, and poses problems with geomorphology, geology, and tectonic setting of Kashmir basin. The major flaw of the model remains its orientation, and geometry, because a major dextral fault, which form a pull-apart basin, cannot cut through the center of a basin. It is therefore shown that the recently suggested pull-apart model is structurally impossible, and thus the Central Kashmir Fault (CKF), a proposed major dextral fault of Alam et al. (2015), could not exist.

Dextral strike-slip faulting in the Cariboo Mountains, British Columbia: a natural example of wrench tectonics in relation to Cordilleran tectonics

2002 ◽  
Vol 39 (6) ◽  
pp. 953-970 ◽  
Author(s):  
L F Reid ◽  
P S Simony ◽  
G M Ross
Keyword(s):  
British Columbia ◽  
Rocky Mountain ◽  
Strike Slip ◽  
Strike Slip Fault ◽  
Fault System ◽  
Fault Systems ◽  
Dextral Strike Slip Fault ◽  
Deformation Event ◽  
Step Over ◽  
Dextral Strike Slip

The Cariboo Mountains, British Columbia, contain an intracontinental dextral strike-slip fault system that crosscuts the regional fold structures. This fault system accounts for a minimum of 120 km and a maximum of 200 km of dextral strike-slip displacement. This probably accommodates some of the motion associated with the southern termination of the Northern Rocky Mountain Trench Fault and is part of a step-over zone between the Northern Rocky Mountain Trench Fault and the Fraser River – Straight Creek fault systems. The Isaac Lake Synclinorium is a kilometre-scale Jurassic fold structure that is bounded by the dextral oblique Isaac Lake and Winder strike-slip faults. These faults are part of the regional strike-slip fault system that is found throughout the Cariboo Mountains. Deformation associated with the strike-slip faults is complex and is partitioned into motion along the faults and into the formation of kilometre-scale folds that are found in areas between the faults. The angular relationship between the strike-slip faults and folds conforms to models developed for dextral strike-slip fault systems with drag on high-friction faults. We interpreted these structures to have formed during a continuous deformation event. Timing constraints indicate that faulting started by the Late Cretaceous and may have had a long and protracted history into the Tertiary.

scholarly journals Coseismic fault-slip distribution of the 2019 Ridgecrest Mw6.4 and Mw7.1 earthquakes

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yang Gao ◽  
HuRong Duan ◽  
YongZhi Zhang ◽  
JiaYing Chen ◽  
HeTing Jian ◽  
...  
Keyword(s):  
Strike Slip ◽  
Fault Slip ◽  
Slip Distribution ◽  
Synthetic Aperture ◽  
Seismic Events ◽  
Interferometric Synthetic Aperture Radar ◽  
The Past ◽  
Dextral Strike Slip Fault ◽  
Fault Slip Distribution ◽  
Dextral Strike Slip

AbstractThe 2019 Ridgecrest, California seismic sequence, including an Mw6.4 foreshock and Mw7.1 mainshock, represent the largest regional seismic events within the past 20 years. To obtain accurate coseismic fault-slip distribution, we used precise positioning data of small earthquakes from January 2019 to October 2020 to determine the dip parameters of the eight fault geometry, and used the Interferometric Synthetic Aperture Radar (InSAR) data processed by Xu et al. (Seismol Res Lett 91(4):1979–1985, 2020) at UCSD to constrain inversion of the fault-slip distribution of both earthquakes. The results showed that all faults were sinistral strike-slips with minor dip-slip components, exception for dextral strike-slip fault F2. Fault-slip mainly occurred at depths of 0–12 km, with a maximum slip of 3.0 m. The F1 fault contained two slip peaks located at 2 km of fault S4 and 6 km of fault S5 depth, the latter being located directly above the Mw7.1hypocenter. Two slip peaks with maximum slip of 1.5 m located 8 and 20 km from the SW endpoint of the F2 fault were also identified, and the latter corresponds to the Mw6.4 earthquake. We also analyzed the influence of different inversion parameters on the fault slip distribution, and found that the slip momentum smoothing condition was more suitable for the inversion of the earthquakes slip distribution than the stress-drop smoothing condition.

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