Rose diagram sinistral dextral movement
The Miocene is a time of great tectonic change that ushered in the modern tectonic regime. These grabens dominate the subsequent tectonic movement and are still very active as northwest‐trending dextral‐slip faults northwest of the mountains. The Gulu, Damxung‐Yangbajain and Angan graben systems that pass east of the Nyainqĉntanglha Mountains are locally controlled by the earlier northeast‐trending faults. The regional uplift of the southern Tibetan Plateau thus appears to have occurred between 8.3 Ma and 6.5 Ma. This relatively local uplift that left adjacent Eocene and Miocene deposits preserved was followed by a regional uplift and the initiation of a system of generally north‐south grabens in the Late Miocene at ∼6.5 Ma. The latter are replaced farther to the east by the west‐northwest‐trending Lhünzhub thrust faults with dextral‐slip. EXERCISE 1A: Geological Attitudes and 3D Block Diagram Interpretation. Northwest‐trending dextral‐slip faults formed to the northwest of the raisen batholith, whereas the northeast‐trending South Damxung thrust faults with some sinistral‐slip formed to the southeast. The dextral‐slip movement ended at ∼11 Ma and the batholith rose, as marked by gravitational shearing at 8.6–8.3 Ma, and a new fault system developed. Field evidence supports that the sinistral slip movement along the NW-trending faults occurred prior to that of the dextral motion. These faults were took shape by the Early Miocene, and the large Nyainqĉntanglha granitic batholith formed along the thrust system in 18.3–11.0 Ma as the western block drove under the eastern one. trending joints and faults show both dextral and sinistral slip movement and additionally the NW-SE trending lineaments display both dextral and sinistral senses. The east‐west dextral‐slip Gangdise fault system merges eastward into the northeast‐trending, southeast‐dipping Nyainqĉntanglha thrust system that swings eastward farther north into the dextral‐slip North Damxung shear zone and Jiali faults. Xun, ZHAO Zhonghai, WU Daogong, HU Qisheng, LIUĪbstract: Dextral‐slip in the Nyainqĉntanglha region of Tibet resulted in oblique underthrusting and granite generation in the Early to Middle Miocene, but by the end of the epoch uplift and extensional faulting dominated. Ces nouvelles observations apportent d’importantes indications pour la reconstitution des structures pré-Crétacé entre l’Oural et le Tien Chan.Miocene Tectonic Evolution from Dextral‐Slip Thrusting to Extension in the Nyainqĉntanglha Region of the Tibetan Plateau Miocene Tectonic Evolution from Dextral‐Slip Thrusting to Extension in the Nyainqĉntanglha Region. Les structures principales sont des failles décrochantes dextres orientées nord–ouest. L’événement triasique D3 avec raccourcissement en direction nord–sud reflète la collision du microcontinent de Turan contre la marge méridionale du Kazakhstan. Les structures principales sont des plis subméridionaux et des failles décrochantes sénestres orientées nord–sud. L’événement D2 fini-Permien et triasique est contrôlé par une compression en direction est–ouest qui reflète une déformation collisionnelle dans l’Oural. L‘événement D1 au Carbonifère tardif se caractérise par des structures de charriage et plissement de style Laramide, sur la marge nord du Kazakhstan, avec raccourcissement en direction NE–SW. Dans la déformation, trois événements sont reconnus. Sur l’exemple de la dorsale de Karatau dans le territoire du Sud Kazakhstan, on discute l‘histoire de la déformation au cours du Paléozoïque tardif à la jonction Oural–Tien Chan.