Geology and Tectonic of Chaman Fault

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2. GEOLOGY AND TECTONIC OF
CHAMMAN FAULT
 Members;
Abdul Majeed Bughio
M.A Dahri
Shazan Qureshi
Assigned By;
M.Afzal Jamali
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3. CHAMAN
 Chaman ‫چمن‬) is the capital of Qilla Abdullah
District, Balochistan Province, Pakistan. It is
situated just south of the West-Chaman
border crossing with the
neighbouring Kandahar
Province of Afghanistan. After the
capital Quetta, Chaman is the second-
largest city and tehsil in
the Pashtun majority northern part of
Balochistan Province.
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5. CHAMAN FAULT
The Chaman Fault is a major,
active geological
fault in Pakistan and Afghanistan that
runs for over 850 km.
 Tectonically, it is actually a system of
related geologic faults that separates
the Eurasian Plate from the Indo-
Australian Plate.
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 It is a terrestrial, primarily transform, left-
lateral strike-slip fault. The slippage rate along the
Chaman fault system as the Indo-Australian Plate
moves northward (relative to the Eurasian Plate)
has been estimated at 10 mm/yr or more

9.  In addition to its primary transform aspect, the
Chaman fault system has a compressional
component as the Indian Plate is colliding with the
Eurasian Plate.
 This type of plate boundary is sometimes called a
transpressional boundary.
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10.  From the south, the Chaman fault starts at the triple
junction where the Arabian Plate, the Eurasian Plate and
the Indo-Australian Plate meet, which is just off
the Makran Coast of Pakistan.
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11.  The fault tracks northeast
across Balochistan and then north-northeast
into Afghanistan, runs just to the west
of Kabul, and then northeastward across the
right-lateral-slip Herat fault, up to where it
merges with the Pamir fault system north of
the 38° parallel.
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12. The Ghazaband and Ornach-Nal
faults are often included as part of
the Chaman fault system. South
of the triple junction, where the
fault zone lies undersea and
extends southwest to
approximately 10°N 57°E, it is
known as the Owen Fracture
Zone.
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13. Seismotectonic Context
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15. While there is general agreement
that the fault is slipping at a rate of
at least 10 mm/yr, there is a report
of volcanic rocks in Pakistan
dated to 2 m.y. BP which have
been offset such as to indicate a
slip rate of 25–35 mm/yr.
 Offsets have been described
throughout the fault in Pakistan
that are young enough that “only
the alluvium of the bottom of
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16. The parallel mountain ranges of
eastern Balochistan, (east to west)
the Kirthar Mountains, the Khude
Mountains, the Zarro Mountains, the
Pab Mountains and the Mor
Mountains, are a result of the
compressional plate boundary and are
aligned parallel to the Chaman fault
movement. The fault itself is west of
these ranges.
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17. OTHER FAULTS IN PAKISTAN
 Main Karakoram Thrust.
 Riasi Thrust.
 Salt Range Thrust.
 Bannu Fault.
 Quetta-Chiltan Fault.
 Allah Bund Fault.
 Hoshab Fault.
 Makran Coastal Fault
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19. MAJOR EARTHQUAKE PRODUCE BY CHAMMAN FAULT
 On September
2013, a 7.7
magnitude earthqua
ke was recorded
along a fault
associated with
the Chaman
fault system in
southern Pakistan.
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20. CONCLUSION
 Rupture initiated at the southern tip of the Chaman Fault and
propagated along the Hosbah fault within the Makran
accretionnary prism
 Large strike-slip motion (6m on average, along 200km long
fault trace, 0-12km depth) on pre-existing thrust fault
 Strike-slip enhanced due to eastward squeezing of Makran
prims
 No shallow slip deficit
 Large rupture velocity on
misoriented fault
 Rupture failed to propagate along
the Chaman fault (despite most
aftershocks there).

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