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An updated kinematic model constrained by GPS observations and fault slip rate information from the Central Asia Fault Database provides updated modeled slip rates for major faults in the Pamir. The kinematic model constrains thin sheet continuum mechanics models that distinguish the contributions of subducting continental lithosphere to force balance. Dynamic model sensitivity tests show that major features of the force balance results are insensitive to chosen lithospheric compensation style, integration depth, and inclusion of subducting low‐density continental lithosphere in the upper 100 km. Forward models incorporate deviatoric stresses associated with gravitational potential energy, velocity boundary conditions, and lateral strength variations. Differential strain rate fields, which represent residual forces not accounted for in the forward models, separate and quantify the deformation associated with the Pamir slab. The downward pull of foundering lithosphere augments compression along the Pamir Frontal Thrust System and shear along the eastern and western Pamir boundaries. North‐south extension in the residual differential strain rate field is spatially associated with Pamir gneiss domes and may be related to the interaction of the slab with the mantle. We do not find evidence for slab pull associated with a separate Hindu Kush slab. Surface deformation is controlled by a balance of body forces, lateral boundary forces, and pull from the subducting Pamir slabSubduction contributes compression normal to the Pamir Frontal Thrust System and shear at the eastern and western Pamir boundariesLateral variations in trench‐normal compression reflect differences in deeper slab dynamics between the Pamir and Hindu Kush

Kinematic and dynamic models quantify deformation and force balance in the Pamir, a region undergoing the rare and poorly understood process of intracontinental subduction. We constrain a detailed kinematic model with 506 recent GPS velocities and Quaternary fault slip rates and show that the Pamir is organized like the Himalaya and Tibet, with regions of (1) localized strain rate ≥100e‐9/year along the Pamir Frontal Thrust System (the subduction interface), similar to the Himalaya, and (2) distributed north‐south compression and east‐west extension, similar to Tibet. Through standard thin viscous sheet methods we demonstrate that the lithospheric force balance in the Pamir is a combination of stresses caused by gravitational potential energy and India‐Eurasia convergence accommodated at a subduction interface, in this case the Pamir Frontal Thrust System. We find that strain rate and deviatoric stress patterns near the Pamir Frontal Thrust System are characteristic of a mature subduction zone, despite its initiation in continental lithosphere. Although the Pamir and Tibet are kinematically and dynamically similar, the Pamir is stiffer overall than Tibet, perhaps due to the presence of the highly arcuate, geometrically stiffened continental slab at depth. The Pamir is kinematically organized like the Himalaya and Tibet with localized (subduction‐like) and distributed (plateau‐like) deformationStress patterns near the subduction interface indicate a mature subduction zone, despite initiation in continental lithosphereThe Pamir is stiffer than Tibet, likely due to the presence of a geometrically stiffened, subducting continental slab

Vertical GPS displacement time series from 16 continuous sites over a period from 2007 to 2014 are compared to time series of monthly averages of liquid water equivalent thickness from the Gravity Recovery and Climate Experiment and precipitation from the Climate Research Unit to investigate hydrologic loading in Ethiopia and Eritrea. The GPS vertical time series record the presence of one or two rainy seasons, the amplitude surface displacements in response to monsoon water load, and phases consistent with a purely elastic response to a water load that accumulates throughout the rainy period. Comparison of observed amplitudes to those calculated for an average Earth model shows no systematic weakness related to the rift. GPS vertical displacement correlates to GRACE and CRU monsoon observationsMonsoon water excites an elastic deflection of the surfacePhase lag between peak precipitation and flexure records water storage

GPS velocities measured in the Pamir and surrounding regions show a total of ~30?mm/yr of northward relative motion between stable Pakistan and Eurasia. The convergence budget is partitioned into 10–15?mm/yr of localized shortening across the Trans-Alai Thrust, which bounds the Pamir on the north, consistent with southward subduction of intact lithosphere. Another 10–15?mm/yr of shortening is distributed across the Chitral Himalaya and Hindu Kush, suggesting that Hindu Kush seismicity might be related to northward subduction of Indian lithosphere. Modest shortening at <5?mm/yr occurs north of the Trans-Alai Thrust, across the South Tien Shan and between the Ferghana Valley and Eurasia. Negligible north-south shortening occurs within the high Pamir, but as much as 5?mm/yr, and perhaps 10?mm/yr, of east-west extension occurs within this region. This extension is matched by a comparable amount of east-west shortening in the Tajik Depression. The localization of shortening to the margins of the Pamir combined with observations of distributed internal extension implies that the east-west vertically averaged, horizontal compressive normal stress is smaller than the north-south compressive stress. There is a major surface zone of shortening corresponding to the Hindu KushThere are two marginal north-south shortening zones bounding the PamirEast-west extension of the Pamir matches shortening in the Tajik Depression