Abstract In 24 March 2011, an earthquake on the scale of M w 6.8 occurred at the west end of the Nam Ma Fault, which is 215 km long, crossing Myanmar, Laos and China. The rupture occurred on a 30 km-long segment in Myanmar. The earthquake was limited to individual segments, reducing its magnitude. The ASTER GDEM is accessible from a download site. Its relief map illustrates linear features reflecting fault scarps, step-overs, pull-apart areas and bends associated with tectonic deformation. A harmonized geological map of the study area that was continuous over the cross-border areas was compiled. The map reveals lithologies, ages of formations, continuous displacement lines and exotic terranes. Intensive field surveys provided information on tectonics in Myanmar while on the Laos side intensive surveys were not conducted. The ASTER GDEM data and the harmonized geological maps were used to support mapping of the entire segmentation of the Nam Ma Fault. The mapped Nam Ma Fault consists of five segments. Estimated slip-plane areas and magnitudes of possible earthquakes of the respective segments indicate that the greatest magnitude is 7.3 in the case of rupture of a 100 km long segment.

Abstract Northern Thailand is located in a structurally complex area between three major tectonic regimes, a region of extensional tectonics to the south and two major strike-slip zones, the Sagaing fault zone to the west and the Red River fault zone to the northeast. Cenozoic tectonics in northern Thailand resulted from the collision between the Indian plate and Eurasia. The continued indentation of the Indian plate into Eurasia caused polyphase extrusion of Sundaland and the movement of major strike-slip faults. The movement of these faults accompanying the regional east-west extension during Late Oligocene to Early Miocene initiated the formation of the Tertiary basins. Thirty-six major faults and forty-two intra-cratonic depositional basins in northern Thailand have been recognized and delineated using Landsat TM images. More than 70% of these basins are related to strike-slip tectonics. Five basin types have been recognized on the basis of geometric and kinematic considerations. These are fault-tip basins, pull-apart basins, fault-wedge basins, fault zone basins, and extensional basins. The opening and development of these basins was influenced by the movement of NW-trending dextral faults and NE-trending sinistral faults associated with north-south shortening and east-west extension.