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A multidisciplinary seismic survey earlier this year in the Pacific Northwest is expected to reveal much new information about the earthquake threat to U.S. and Canadian urban areas there. A disastrous earthquake is a very real possibility in the region. The survey, known as the Seismic Hazards Investigation in Puget Sound (SHIPS), engendered close cooperation among geologists, biologists, environmental groups, and government agencies. It also succeeded in striking a fine balance between the need to prepare for a great earthquake and the requirement to protect a coveted marine environment while operating a large airgun array.

The timing and size of the last great earthquake in the central Himalaya continues to excite scientific controversy, despite a decade of palaeoseismological investigations. The studies along the frontal thrust in the Indian part of the central Himalaya disclose a faulting event between 14th and 15th century, and a dominant view presupposes the 1505 CE earthquake as the likely source. Here we evaluate the database along with independent inputs to determine the timing of the last faulting event on the frontal thrust of the central Himalaya. From the historical perspective, the Nepalese archives make a direct reference to a significant earthquake in 1344 CE, and the Indian sources hint at a restoration phase for the mid‐14th century monuments in the northern plains and coeval destruction to the ancient temples in the central Himalaya. Aside from the constraints generated from the earthquake proxies including liquefaction features and deformed stalagmites, the previous and currently acquired geological data from multiple trenches across the frontal thrust show that the last faulting event occurred between 13th and 14th centuries—the time interval coinciding with the 1344 CE earthquake. The episodic valley fills debris flow depositions identified in the Pokhara Valley in the east‐central Nepal provide additional constraints for the 1344 CE earthquake along with two previous ones in 1255 and 1100 CE. The consilience of multiple pieces of evidence from India and Nepal in combination with the new data inputs from two trench locales implicates the 1344 CE as the last of the medieval sequence of earthquakes. With a rupture length of ~600 km of the central Indian Himalaya and an average slip of 15 m, this earthquake is consistent with moment magnitude of Mw ≥8.5. An earthquake of similar size is overdue in this part of the Himalaya, considering the long elapsed time of ≤700 years.

As many as seven tsunamis from the past 8000 years are evidenced by sand sheets that rest on buried wetland soils at Badabalu, southern Andaman Island, along northern part of the fault rupture of the giant 2004 Aceh-Andaman earthquake. The uppermost of these deposits represents the 2004 tsunami. Underlying deposits likely correspond to historical tsunamis of 1881, 1762, and 1679 CE, and provide evidence for prehistoric tsunamis in 1300–1400 CE, in 2000–3000 and 3020–1780 BCE, and before 5600–5300 BCE. The sequence includes an unexplained hiatus of two or three millennia ending around 1400 CE, which could be attributed to accelerated erosion due to Relative Sea-Level (RSL) fall at ~3500 BP. A tsunami in 1300–1400, comparable to the one in 2004, was previously identified geologically on other Indian Ocean shores. The tsunamis assigned to 1679, 1762, and 1881, by contrast, were more nearly confined to the northeast Indian Ocean. Sources have not been determined for the three earliest of the inferred tsunamis. We suggest a recurrence of 420–750 years for mega-earthquakes having different source, and a shorter interval of 80–120 years for large magnitude earthquakes.

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