The Main Frontal Thrust (MFT) , also known as the Himalayan Frontal Thrust (HFT) , is a geological fault in the Himalayas that defines the boundary between the Himalayan foothills and Indo-Gangetic Plain . The fault is well expressed on the surface thus could be seen via satellite imagery. It is the youngest and southernmost thrust structure in the Himalaya deformation front . It is a splay branch of the Main Himalayan Thrust (MHT) as the root décollement .
8-752: It runs parallel to other major splays of the MHT; Main Boundary Thrust (MBT) and Main Central Thrust (MCT). The Sunda Megathrust , which extends from the Banda Islands to Myanmar is joined with the MFT. The fault strikes in a NW-SE direction and dips at an angle of 20° to 30° in the north. The Main Boundary Thrust is another major thrust fault in the Himalaya orogenic wedge that was active in
16-420: Is a megathrust , located at a convergent plate boundary where it forms the interface between the overriding Eurasian plate and the subducting Indo-Australian plate . It is one of the most seismogenic structures on Earth, being responsible for many great and giant earthquakes , including the 2004 Indian Ocean earthquake and tsunami that killed over 227,000 people. The Sunda megathrust can be divided into
24-419: Is segmented. The largest earthquakes occur on separate 'patches' along the megathrust surface ( 1797 , 1833 , 1861 , 2004 , 2005 & 2007 ), with smaller events occurring at the boundaries between these patches ( 1935 , 1984 , 2000 & 2002 ). The rupture area of the 1861 event appears to be very similar to that for the 2005 event, suggesting that it can be regarded as a repeat event. The 2007 event
32-576: The Andaman Megathrust , Sumatra(n) Megathrust and Java(n) Megathrust . The Bali - Sumbawa segment is much less active and therefore does not have the "megathrust" term associated with it. The subducting plate consists of two protoplates, the Indian plate and Australian plate . Similarly, the overriding plate consists of two microplates, the Sunda and Burma plates. The relative motion of
40-518: The Cenozoic . It runs parallel to the MFT with a spacing distance of about 20 km. Shortening rate varies across the MFT, these figures provide the speed in various locations. The MFT accommodates almost the entire rate of subduction of the Indian Plate therefore, it is no surprise that numerous earthquakes have occurred along this fault, and is expected to produce very big earthquakes in
48-512: The future. Many earthquakes associated with the MFT has resulted in visible ground ruptures , as seen in the Bihar earthquake of 1934 and 1505 magnitude 8.2-8.8 earthquake . Sunda megathrust The Sunda megathrust is a fault that extends approximately 5,500 km (3300 mi) from Myanmar (Burma) in the north, running along the southwestern side of Sumatra , to the south of Java and Bali before terminating near Australia . It
56-601: The subducting and overriding plates varies slightly along strike due to these complexities but is always strongly oblique. The strike-slip component of the oblique convergence is accommodated by displacement on the Great Sumatran fault , while the dip-slip component is taken up by the Sunda megathrust. The Sunda megathrust is curviplanar, forming an arc in map view and, at least in Sumatra, increasing in dip from 5°-7° near
64-470: The trench, then increasing gradually from 15°-20° beneath the Mentawai Islands to about 30° below the coastline of Sumatra. At this plate boundary, earthquakes occur along the Sunda megathrust and within both the subducting and overriding plates. The largest earthquakes are generated when the megathrust itself ruptures. Studies of both recent and historical earthquakes show that the megathrust
#542457