
The Main Frontal Thrust (MFT), also known as the Himalayan Frontal Thrust (HFT) is a geological
fault in the
Himalayas
The Himalayas, or Himalaya (; ; ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the planet's highest peaks, including the very highest, Mount Everest. Over ...
that defines the boundary between the
Himalayan foothills and
Indo-Gangetic Plain
The Indo-Gangetic Plain, also known as the North Indian River Plain, is a fertile plain encompassing northern regions of the Indian subcontinent, including most of northern and eastern India, around half of Pakistan, virtually all of Bangla ...
.
The fault is well expressed on the surface thus could be seen via satellite imagery. It is the youngest and southernmost
thrust
Thrust is a reaction force
In physics, a force is an influence that can change the motion of an object. A force can cause an object with mass to change its velocity (e.g. moving from a state of rest), i.e., to accelerate. Force can al ...
structure in the Himalaya
deformation front. It is a splay branch of the
Main Himalayan Thrust
The Main Himalayan Thrust (MHT) is a décollement under the Himalaya Range. This thrust fault follows a NW-SE strike, reminiscent of an arc, and gently dip towards the north, beneath the region. It is the largest active continental megathrust ...
(MHT) as the root
décollement
Décollement () is a gliding plane between two rock masses, also known as a basal detachment fault. Décollements are a deformational structure, resulting in independent styles of deformation in the rocks above and below the fault. They are ass ...
.
It runs parallel to other major splays of the MHT; Main Boundary Thrust (MBT) and Main Central Thrust (MCT). The
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 is a ...
, which extends from the Banda Islands to
Myanmar
Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John Wells explai ...
is joined with the MFT.
The fault
strikes
Strike may refer to:
People
*Strike (surname)
Physical confrontation or removal
*Strike (attack), attack with an inanimate object or a part of the human body intended to cause harm
*Airstrike, military strike by air forces on either a suspected ...
in a NW-SE direction and
dips at an angle of 20° to 30° in the north.
Main Boundary Thrust
The Main Boundary Thrust (MBT) is another major thrust fault in the Himalaya orogenic wedge that was active in the
Cenozoic
The Cenozoic ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterised by the dominance of mammals, birds and flowering plants, a cooling and drying climate, and the current configu ...
.
It runs parallel to the MFT with a spacing distance of about 20 km.
Shortening rate
Shortening rate varies across the MFT, these figures provide the speed in various locations.
Seismic activity
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 the future.
[{{Cite book, last1=Bilham , first1=R. , editor1-last=Treloar , editor1-first=P.J. , editor2-last=Searle , editor2-first=M.P. , title=Himalayan Tectonics: A Modern Synthesis , chapter=Himalayan earthquakes: a review of historical seismicity and early 21st century slip potential , series=Geological Society, London, Special Publications , year=2019 , volume=483 , pages=423–482 , doi=10.1144/SP483.16, isbn = 9781786204059, s2cid=133821585 ] 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.
Reference
Tectonics
Himalayas
Active faults
Structural geology
Seismic faults
Seismic faults of Asia
Thrust faults
Seismic faults of Pakistan
Geology of the Himalaya
Subduction zones
Geology of Asia
Geology of Nepal
Geology of Pakistan
Geology of India
Geology of China
Geology of Bhutan