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The northeastern Tibetan Plateau and its surroundings are a tectonically complex region resulting from the continuing collision of India with Eurasia. We studied the tectonic deformation of this region using a GPS block model, which was produced using the most recently published, dense, precise, and complete GPS velocities available combined with a detailed fault geometry. The comparison between our preferred model with numerous faults and a model with fewer faults demonstrates the need for inclusion of lesser active faults affords a closer examination of strain partitioning. The predicted senses of motion and slip rates of active faults in our preferred model are consistent with the geological estimates, supporting the assumption that the decadal GPS slip rates are representative of millennial‐scale geologic slip rates. The observed fault kinematics in the northeastern Tibetan Plateau and its surroundings can be interpreted as the consequence of relative motions between different blocks and block rotations. Key Points: The inclusion of secondary active faults in block modeling affords a closer examination of strain partitioningThe senses of motion and slip rates of active faults predicted by our model are generally in agreement with geologic observationsDeformation of North Eastern Tibet and its surroundings can be interpreted as the result of relative motions between blocks and block rotations [ABSTRACT FROM AUTHOR]

Deciphering the relationship between lateral growth of faults and along‐strike deformation (i.e., shortening and uplift) in the Earth's upper crust remains a challenge. Here we gain insight into the relation between these processes by studying the Kashi anticline, an asymmetric, doubly plunging thrust‐fault‐related fold located in the southwest Tian Shan, China. We use seismic interpretation and field observations, together with 2‐D trishear and excess area methods, to quantify the distribution of shortening along this structure. The shortening distribution along strike of the Kashi anticline is nonlinear and has a peaked, asymmetric, bell shape, with a maximum value of 5.9 ± 0.2 km. After comparing the 3‐D structural model of the Kashi anticline and our trishear models, we propose that lateral propagation‐to‐maximum shortening ratio, initiation fault length, and lateral propagation rate control the lateral fault propagation process and the fold terminations. Moreover, the 3‐D fault morphology and the ages of the growth strata suggest that the Kashi anticline experienced two stages of lateral growth with propagation rates of 60 km/Ma between 1.4 ± 0.2 Myr and 0.9 ± 0.3 Ma, and ~67 km/Myr from 0.9 ± 0.3 Ma to present. These observations highlight the relation between the evolution of lateral fault growth and the along‐strike shortening distribution, allowing us to use the latter (which we can measure) to infer the former (which we cannot). These novel insights from the Kashi anticline can be used to understand lateral growth of thrust and normal faults worldwide. Key Points: Structural interpretations reveal that the western segment of Kashi anticline is a trishear fault propagation fold, whereas the eastern segment is a detachment foldVariations of lateral fault growth produced along‐strike shortening distribution with a peaked, nonlinear bell shapeKashi anticline experienced two stages of lateral growth with propagation rates of 60 km/Myr between 1.4 ± 0.2 and 0.9 ± 0.3 Ma, and ~67 km/Myr from 0.9 ± 0.3 Ma to present [ABSTRACT FROM AUTHOR]