Nuclear tests at Mt. Mantap have reactivated intraplate faults

September 17, 2026| Source: Science

Underground nuclear explosions typically produce short-lived seismic sequences that decay rapidly after testing ceases. By contrast, seismicity near the Punggye-ri nuclear test site at Mt. Mantap in the Democratic People’s Republic of Korea has persisted and intensified for years after the final large-yield explosion in 2017, evolving from diffuse activity to spatially organized distribution along fault-controlled structures. Analysis of 17 years of continuous waveform data reveals a progressive increase in seismicity and delayed reactivation of shallow faults. Earthquakes cluster beneath asymmetric topography, indicating progressive stress redistribution within a critically stressed crustal volume. These observations challenge conventional expectations, showing that under specific geological conditions, underground nuclear testing can drive multiyear fault reactivation and extend posttest seismicity well beyond the immediate aftermath of an explosion.

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Extensive glacier loss in the coterminous United States.

Glaciers populate the mountain ranges of the western conterminous United States and despite their importance to alpine hydrology, their area and volume change have never been comprehensively evaluated. Our study shows that since the mid-twentieth century about one-quarter of the glaciers have disappeared and the overall area and volume are reduced by one-third. The pattern of glacier shrinkage suggests most glaciers in the conterminous United States are largely maintained by local topographic in

Physical/TechOctober 20, 2026

Reaction-based cryo-EM resolves the continuous conformational spectrum of CTP synthase catalysis.

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Physical/TechOctober 20, 2026

GTP orchestrates CTP synthase via an allosteric effector-cycling mechanism.

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Physical/TechOctober 20, 2026

Antiferromagnetism and tightly bound Cooper pairs induced by kinetic frustration.

Antiferromagnetism and superconductivity are often viewed as competing orders in correlated electron systems. Here, we demonstrate that kinetic frustration in hole motion facilitates their coexistence within the square-lattice repulsive Hubbard model. Combining exact analytical solutions on tailored geometries with large-scale numerical simulations, we reveal a robust pairing mechanism: Holes on opposite sublattices behave as if they carry opposite effective charges due to spin singlet formation

Physical/TechOctober 20, 2026

Coordinated transformations of the labyrinth and occiput during the dinosaur-bird transition.

Evolutionary shape changes of the vertebrate semicircular canals (SCCs) are often ascribed to evolutionary transitions in locomotion, including the origin of flight during the dinosaur-bird transition. However, the potential for transformations of braincase architecture to influence SCC shape independent of sensory-functional adaptation has generally been overlooked. We evaluate the influence of both factors using a large dataset of 146 living and recently extinct crown birds, including taxa rep