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Studying the driving force of intracratonic uplifts is important in understanding the deformation mechanism of continental lithosphere and the role of mantle dynamics. The Adirondack Mountains are located at the eastern Laurentian margin in the northeastern United States forming a distinct domal uplift. Subsurface structural constraints on their uplift mechanism are limited. Here we construct a high-resolution velocity model for the crust and mantle lithosphere using full-wave ambient noise tomography. A distinct low shear velocity anomaly with a diameter of similar to 70-100km is imaged beneath the Moho at the Adirondack Mountains. This anomaly is connected with the large-scale low-velocity volume beneath southern New England and eastern New York at greater depths. The observed low-velocity anomalies may reflect asthenosphere upwelling induced by a combined effect of the Great Meteor hot spot and edge-driven mantle convections. The buoyancy of upwelling asthenosphere, together with possible thermal expansion, may have uplifted the Adirondack Mountains.

Plain Language Summary The formation of the Adirondack Mountains in northeastern New York state has been mysterious to scientists. A few mechanisms have been proposed, though deep structural constraints on evaluating those hypotheses are limited. Using an advanced seismic imaging method, we have constructed a detailed model of the lithosphere (the crust and mantle parts of the tectonic plates) in the northeastern United States, down to the depth of about 100km. We discovered a pillow of anomalously low seismic speed with a diameter of similar to 70-100km, at the depths of 50-85km beneath the Adirondack Mountains. This low-speed column is connected, at greater depths, with the broader low-speed anomaly beneath the southern New England and eastern New York region. These low-speed features may have resulted from the rising of asthenosphere, a weak layer beneath the lithosphere. The upward force of the upwelling asthenosphere flow, together with possible thermal expansion, may have provided the mechanism that formed the Adirondack Mountains.