Collaborative research: fault or not? Unraveling the role of himalayan lineaments in controlling geohazards and structural segmentation

The National Science Foundation Division of Earth Sciences awarded Pomona College $351,604 on August 1, 2026, under the Geosciences program (CFDA 47.050) to investigate whether Himalayan lineaments in central Nepal are active strike-slip faults that influence crustal deformation and earthquake rupture patterns.

The research focuses on the Gaurisankar, Thaple, Judi, and Pokhara lineaments in central Nepal, which transect major Himalayan faults and potentially affected rupture behavior during the 2015 magnitude 7.9 Gorkha earthquake and its magnitude 7.3 aftershock. The project tests the hypothesis that these relatively straight landscape features are Cenozoic strike-slip fault systems that accommodate crustal motion and modulate earthquake rupture extents. The research combines remote sensing, field mapping, structural geology, petrology, and geochronology to evaluate the origin, geometry, and activity of these features. Results will inform earthquake hazard assessment and mitigation strategies for protection of structures and populations at risk in seismic zones. The project will train U.S. students in modern geological research skills and disseminate findings to the scientific community and public.

Performance occurs at Pomona College's location in Claremont, California. The award period runs from August 1, 2026, through July 31, 2029.

Abstract

Earthquakes in the himalaya, such as the powerful 2015 nepal earthquake, put millions of people at risk. These mountains are located alongside crustal faults and linear landscape features called lineaments. This project will study whether the lineaments are faults that can influence or trigger earthquakes. Understanding potential hazards can improve earthquake safety, lower landslide damage, and protect structures. This project will use fieldwork, satellite images, earthquake records, and laboratory tests to study the lineaments. The researchers will train U.S. Students on modern skills in geology. Projects findings will be shared with the scientific community and the public to increase understanding of earthquake hazards and their associated risks. This project will investigate whether himalayan lineaments are active strike-slip faults that influence crustal deformation and earthquake rupture patterns in nepal. Lineaments are relatively straight landscape features and are not interpreted as faults unless sufficient evidence exists to classify them as such. The study will focus on the gaurisankar, thaple, judi, and pokhara lineaments in central nepal, which cut across major himalayan faults and potentially affected rupture behavior during the 2015 MW 7.9 gorkha earthquake and its MW 7.3 aftershock. Although lineaments are widely recognized, their origin and significance remain poorly understood. The research is based on the hypothesis that they are cenozoic, strike-slip fault systems that transect the himalayan orogen, accommodate crustal motion, and modulate earthquake rupture extents. The project combines remote sensing, field mapping, structural geology, petrology, and geochronology to evaluate the origin, geometry, and activity of these features. The project will test whether the lineaments are deeply rooted faults or non-tectonic geomorphic features. The results will improve the basic understanding of the structure of the himalayan orogen and help train students in modern geohazard research. The project will produce public maps and data to help local communities improve planning and infrastructure resilience. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the foundation's intellectual merit and broader impacts review criteria.- subawards are not planned for this award.