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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 fault in the world. Overview The MHT accommodates crustal shortening of India and Eurasia as a result of the ongoing collision between the Indian and Eurasian plates. Deformation of the crust is also accommodated along splay structures including the Main Frontal Thrust (MFT), Main Boundary Thrust (MBT), Main Central Thrust (MCT) and possibly the South Tibetan Detachment. The MHT is the root detachment of these splays. At this present moment, the MFT and MHT accounts for almost the entire rate of convergence (15-21 mm/yr). This fault defines where the India subcontinent is underthrust beneath the Himalayan orogenic wedge. In April 2015, a section of the MHT produced a blind rupture earthquake, killing nearly 9,000 Nepalese. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrust Fault
A thrust fault is a break in the Earth's crust, across which older rocks are pushed above younger rocks. Thrust geometry and nomenclature Reverse faults A thrust fault is a type of reverse fault that has a dip of 45 degrees or less. If the angle of the fault plane is lower (often less than 15 degrees from the horizontal) and the displacement of the overlying block is large (often in the kilometer range) the fault is called an ''overthrust'' or ''overthrust fault''. Erosion can remove part of the overlying block, creating a ''fenster'' (or '' window'') – when the underlying block is exposed only in a relatively small area. When erosion removes most of the overlying block, leaving island-like remnants resting on the lower block, the remnants are called ''klippen'' (singular '' klippe''). Blind thrust faults If the fault plane terminates before it reaches the Earth's surface, it is referred to as a ''blind thrust'' fault. Because of the lack of surface evidence, blind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modified Mercalli Intensity Scale
The Modified Mercalli intensity scale (MM, MMI, or MCS), developed from Giuseppe Mercalli's Mercalli intensity scale of 1902, is a seismic intensity scale used for measuring the intensity of shaking produced by an earthquake. It measures the effects of an earthquake at a given location, distinguished from the earthquake's inherent force or strength as measured by seismic magnitude scales (such as the "" magnitude usually reported for an earthquake). While shaking is caused by the seismic energy released by an earthquake, earthquakes differ in how much of their energy is radiated as seismic waves. Deeper earthquakes also have less interaction with the surface, and their energy is spread out across a larger volume. Shaking intensity is localized, generally diminishing with distance from the earthquake's epicenter, but can be amplified in sedimentary basins and certain kinds of unconsolidated soils. Intensity scales empirically categorize the intensity of shaking based on the effect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1991 Uttarkashi Earthquake
The 1991 Uttarkashi earthquake (also known as the Garhwal earthquake) occurred at 02:53:16 Indian Standard Time ( UTC+05:30) on 20 October with a moment magnitude of 6.8 and a maximum Mercalli intensity of IX (''Violent''). This thrust event was instrumentally recorded and occurred along the Main Central Thrust in the Uttarkashi and Gharwal regions of the Indian state of Uttarakhand (then still part of Uttar Pradesh). High intensity shaking resulted in the deaths of at least 768 people and the destruction of thousands of homes. Tectonic setting The Garhwal division in northern India, flanked by the Tons River to the west and the Alaknanda River to the east, is located at the boundary of the Indian and Eurasian tectonic plates. In the region, the Indian Plate is moving northeastward at a rate of per year. The Main Central Thrust is the primary northwest-striking structure and dips to the north at 30–40°. The fault plane solutions from the parametric catalogs for the 1991 an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1988 Nepal Earthquake
The 1988 Nepal earthquake ( ne, विसं २०४५ को भूकम्प) occurred in Nepal near the Indian border and affected much of northern Bihar. The magnitude 6.9 earthquake shook the region on August 21, killing at least 709 persons and injuring thousands. The earthquake struck in two installments of 10 seconds and 15 seconds each and left cracks in 50,000 buildings, including Raj Bhavan and the old Secretariat Building in Patna, Bihar. See also * List of earthquakes in 1988 *List of earthquakes in India *List of earthquakes in Nepal References External links M6.9 - Nepal-India border region– United States Geological Survey Earthquakes in Bihar, India– Amateur Seismic Centre * {{DEFAULTSORT:Nepal Earthquake, 1988 1988 Nepal Earthquake, 1988 1988 1988 earthquakes Natural disasters in Bihar Earthquake An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
