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CHAPTER-1
Introduction
Chapter -1 Introduction
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CHAPTER-1
INTRODUCTION
1.1. Introduction
Mountain belts formed by continent-continent collision are perhaps the most
dominant geologic features of the surface of the Earth (Dewey and Burke, 1973). The
Himalaya is a classic example of an orogenic system created by continent–
continent collision ( Dewey and Bird, 1970; Dewey and Burke, 1973; Molnar and
Tapnier, 1975; Replumaz and Tapponnier, 2003; Fournier et al., 2004; Najman et al.,
2010; Hall, 2012) and the Himalaya formed by huge tectonic forces contain evidence
of the complete Wilson cycle from the Mesozoic to the Eocene, followed by post-
collisional deformation that is still active. The Himalayan-Tibetan orogeny originated
when the Tethys ocean subducted northward beneath the Asian plate, and the crust of
the Indian and Asian plates began to collide at ~ 55 Ma (Powell and Conaghan, 1973;
Coward and Butler, 1985). Himalaya has extension over 2500 km from north-west
(33o15'N, 74o36'E) to south-east (29o37'N, 95o15'E) strike with an average width
along the entire longitudinal extension ranging from 100-400 km. In the northern side,
Indus-Tsangpo Valley separates the main Himalaya from the Trans-Himalaya. Its
youthfulness and incredible exposure make the orogen best for studying various
geologic processes related to mountain building. Its potential as a guide to interpret
the feedback processes between lithospheric deformation and atmospheric circulation
has encouraged intense research in recent years on the history of the Himalayan
orogen, it has played a significant role in global climate change, and its interaction
with erosion (Harrison et al., 1998; Molnar et al., 1993; Royden et al., 1997;
Ramstein et al., 1997; Tapponnier et al., 2001; Beaumont et al., 2001; Yin et al.,
2002; Yi et al., 2011). Owing to scientific interest, the Himalayan fold-and-thrust
belts have been extensively studied since 1950 after the Himalayan territory was
opened. According to Valdiya (1988), the various postulations on evolution of the
Himalayan Mountains can be put into two categories in which one school of thought
attributes the origin to vertical movements and attendant block faulting along deep
faults and fractures which also served as channel ways for the granitic magmas
(Van Hinsbergen et al., 2011) and the other view is that the orogen came into
existence as a result of horizontal compression of marine sediments, the compression
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resulting from northward drift of the Indian subcontinent and colliding with the
Eurasian plate, the Indus-Tsangpo zone representing the junction of the two
continents (Ali and Aitchison, 2005; Gibbons et al., 2012). India and Asia continued
convergence at the rate of 5 cm/yr estimated from the magnetostratigraphy (Patriat
and Achache, 1984), and the collision was accommodated by major faults along the
Himalaya (Brunel et al., 1983; Macfarlane et al., 1993; Hodges et al., 1996, 2000;
DeCelles et al., 1998a). So south of the suture zone lies the Himalayan thrust belt
which consists of series of south vergent, southward propagating thrust faults (Fig.
1.1) that developed in response to ongoing subduction of Indian plate beneath the
Asian plate (Gansser, 1964; Coward and Butler, 1985; Searle, 1991; Srivastava and
Mitra, 1994; Yin and Harrison, 2000). Because of the ongoing convergence, uplift,
and climate interactions, the Himalayan orogenic system may be the world’s best
geological field laboratory and is the focus of integrated research involving structural
geology, sedimentology, thermobarometry, geochronology and geophysics.
Fig.1.1. Simplified Tectonic map of the Himalayan Orogen (modified after Arora et al., 2012).
The information regarding the history of the collision between India and
Eurasia (i.e. when the last oceanic lithosphere was subducted and continental
lithosphere comes into contact with other continental lithosphere) can be extracted by
examining the timing of deformation, metamorphism, erosion and sedimentation
within the collisional belt (Searle et al., 2003; Aitchison et al., 2007; Guillot et al.,
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2008; Metcalfe, 2013). In view of some authors, the evolution of the orogen involved
some distinct accretion events (Whitmarsh et al., 2001; Aitchison et al., 2007), while
others suggested a single collision event followed by a expanded history (Searle et al.,
1992, 1999; Vance and Harris.,1999; Noble et al., 2001; Walker et al., 2001;
Beaumont et al., 2004; Jamieson et al., 2006; Leech, 2008). These controversial
matters could be determined by increasing detail in terms of the analysis of what geo-
chronological and structural data within the orogen reveals in terms of the evolution
of its tectono-metamorphic stratigraphy, and of its architecture. Alternatively, the
impact of individual accretion events might be evident in plate reconstructions of the
relative motion of India to Eurasia applying ocean floor magnetic anomaly data
(White and Lister, 2012). One key piece of evidence applied to establish when the
collision of the two continents occurred is plate reconstructions of India’s motion
relative to Eurasia. Molnar and Tapponnier (1975) were the first to suggest that a
decrease in the rate of northward movement of India from 100–112 mm/year to 45–65
mm/year at ∼40 Ma represented the collision of India and Eurasia. Consequently,
plate reconstructions also observed a decline in the relative motion of India relative to
Africa, Antarctica and Eurasia (Dewey et al., 1989; Molnar et al., 1988; Patriat and
Achache, 1984; Patriat and Segoufin, 1988). Although there were differences in each
of these models, they all attribute the deceleration of the Indian plate between 55 and
36 Ma to the collision of India and Asia (Jain, 2014) and is consistent with geological
observations that suggest substantial changes occurred in the Himalayan orogen
during this time period (e.g., Rowley, 1996; Guillot et al., 2003). Van Hinsbergen et
al., (2011) suggests the deceleration of India relative to Eurasia may be related to
something other than the collision of the two continents. These researchers
highlighted that India’s motion increased at ∼90 Ma and between ∼65 and 50 Ma.
They suggested that plate acceleration and deceleration could be related to plume
head arrival and increasing continent-plume distance respectively.
Studies along the Himalayan arc that employ an understanding of the
structural architecture using the concepts of fold-thrust belt development (Dhalstrom
et al., 1969; Boyer and Elliott, 1982) have been conducted in Pakistan (Coward and
Butler, 1985), northern India (Srivastava and Mitra, 1994), eastern Nepal (Schelling
and Arita, 1991; Schelling, 1992), western Nepal (DeCelles et al., 2001; Robinson,
2006; Robinson et al., 2008), central Nepal (Pearson, 2002) and western Bhutan
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(McQuarrie et al., 2008). These orogen-scale studies provide a useful method for
understanding the deep structures of the mountain belt and calculating an amount of
upper crustal shortening after the Indo-Asia collision. The shortening values reported
on the above studies can be used to identify along-strike variability of structures and
amount of shortening. These variations in shortening might explain the response of
lithosphere to collision and location of maximum deformation in the Himalaya. These
mountain building activities involve the accumulation of stress and these accumulated
stress are released in the phased manner which leaves behind imprints, in the form of
different patterns of structural elements. The imprints shaped by different
deformational episodes are present as signatures of Himalayan and pre-Himalayan
orogens. Different models have been given by different workers concerning the
Himalayan orogeny from time to time on the basis of different criteria. The
compressional tectonics in the Himalayan region is an accepted fact of field geology
but a number of geological facts, for example limited width (<500km) of the Tethys
ocean, mafic-ultramafic diapirism in an extremely long and narrow lithosphere in the
Indus-Suture Zone, intra-continental ensialic basin in the Tethys region throughout its
long life span have led to alternate models to explain the structural evolution of the
region (Bhat 1984, 1987). In spite of a large number of evolutionary models, a fact is
that the stratigraphy and structural geology of the Himalayan region are not well
understood and it lacks the factual ground data. Dubey (2004) in his publication
narrated the structural evolution of the Himalaya and detailed structural features in
parts of Himalayan region and can be explained with the help of inversion tectonic
model, a model which is totally different from collision tectonics. His model is
essentially based on the field data and can explain the formation of different
generations of folds, faults, and reverse metamorphism. He has also concluded that
the evolution of the Himalaya and other fold belts of India, when considered in
isolation, can be explained with the help of suitable models but when structural trends
and fold orientation data from the Indian subcontinent is considered in entirety none
of the existing models can explain their formation.
1.2. Regional Geology
The Himalaya mountain is a classic example of an orogenic system created by
continent–continent collision (Dewey and Bird, 1970; Dewey and Burke, 1973). The
youthfulness and spectacular exposure make this orogen ideal for studying different
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geologic processes related to mountain building. The Himalaya forms one of the
famous and strongest features in the topography of the world. Himalayan range
outline the Indian subcontinent in a massive 2500 km arc, an icy barrier between the
tropical India and the highlands of Central Asia and lies between its eastern and
western Syntaxis by the Namche Barwa and Nanga Parbat peaks (Fig.1.2).
Fig.1.2. Digital elevation model for the Himalaya. Note the steep front of the Himalayan range towards the South and the huge Tibetan plateau in the North. The two syntaxes near the Nanga Parbat (left) and the Namche Barwa (right) are nicely visible (Yin, 2006). White mark shows the location of the Kashmir Basin in the Himalayan Orogen.
In the Himalayan region and its surrounding, the geomorphology, geologic
structure, and earthquake are result of the northward progression and collision of
India into Eurasia, which accommodated and estimated convergence of 2000-3000km
since the Late Cretaceous (Molnar and Tapponnier, 1978) and continues today at a
rate of about 55 to 60 mm/year (Demets et al., 1994, Bilham et al., 1997, 1998). The
Himalayan mountain system consists of series of southward propagated thrust sheets
which began almost straight away after the collision between Indian and Eurasian
plate in the Eocene (Ratschbacher et al., 1994; Searle et al., 1997; Hodges, 2000;
Richards et al., 2005; Guillot et al., 2008). Himalaya orogen consists/includes three
tectonic slices bounded by three north-dipping Late Cenozoic fault systems which
include Main Boundary Thrust (MBT), the Main Central Thrust (MCT) and the South
Tibetan Detachment System (STD) (Fig.1.1).
The Indian and Asian crusts are separated by Indus-Tsangpo Suture zone
(ITSZ) and are composed of sedimentary rocks, melange, and ophiolitic material.
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There is uncertainty regarding the obduction period of ophiolitic material on the
northern Indian margin. All three tectonic slices are considered to be parts of the north
facing Himalayan passive continental margin commonly known as the Tethyan
Himalaya which developed from middle Proterozoic to Cretaceous times (Brookfield,
1993). Further lying to the south of the Tethys Himalaya, are the metamorphosed
Indian plate rocks of the Higher Himalaya which are bounded by the Main Central
Thrust below and the South Tibetan Detachment fault above (Burg and Chen, 1984;
Burchfiel et al., 1992; LeFort, 1996) and comprises of late Proterozoic to early
Cambrian meta-sedimentary rocks and Tertiary granites (Parrish and Hodges, 1996).
South of the Higher Himalaya lies the Lesser Himalaya consisting of low grade Indian
crustal material of mostly Precambrian to Paleozoic age (Tewari, 1993; Frank et al.,
1995; Hodges, 2000). The Lesser Himalaya is structurally the lowest slice which is
bounded at the base by the Main Boundary Thrust (MBT) and at the top by the Main
Central Thrust (MCT). Further, it is categorized into inner and outer Lesser Himalaya
based on lithological and geochemical differences (Valdiya,1980; Ahmad et al.,
2000). The Sub-Himalayan foreland basin lies South of the Lesser Himalaya
consisting of unmetamorphosed sedimentary rocks which are separated from the
Lesser Himalaya by the Main Boundary Thrust (MBT) (Meigs et al., 1995).
1.2.1. Himalayan divisions
In the Himalayan literature, the geographically, politically, structurally, and
stratigraphically defined Himalaya is often assumed to be interchangeable (LeFort,
1975, 1996). Tectonostratigraphic divisions of the Himalayan orogen is based on
assemblage of rocks enclosed by orogen scale thrust faults. Gansser (1964) divided
the Himalayan orogen into four zones (Fig.1.3). Each zone is then further divided into
formations based on lithology and age. From south to north, the four tectonic
divisions of the Himalayan orogen are: (i) Subhimalaya (Siwaliks); (ii) Lesser
Himalaya; (iii) Greater Himalaya (Higher); (iv) Tibetan-Tehtys Himalaya. Yin (2006)
categorized the Himalayan orogen into north Himalaya and south Himalaya separated
by its high crust line. In this categorization, the North Himalaya is approximately
equivalent to the geographically defined Tethyan Himalaya (Heim and Gansser,
1939) or the Tibetan Himalaya (LeFort, 1975). Following the tradition of Heim
and Gansser (1939) and Gansser (1964), the south Himalaya is divided into Higher,
Lower, and sub-Himalaya from north to south (Fig.1.3).
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Fig.1.3. Tectonostratigraphic division of the Himalaya from Nanga Parbat to the west and Namche Barwa to the east (Gansser, 1964). Equivalent abbreviations using in this study are as follows: Tibetan-Tethys Himalaya/Tibetan Himalaya, Higher Himalaya/Greater Himalaya, Lesser Himalaya/Lesser Himalaya, Siwaliks/Subhimalaya.
1.2.1.1. Sub-Himalaya/Siwaliks
The Sub-Himalaya is the southernmost zone of the Himalayan orogen, and
consists of a foreland basin system that incorporated syntectonic sediments during
Middle Miocene to Pliocene time (~14-2 Ma). The Sub-Himalaya tectonic unit
comprises of Tertiary molasse type sediments which are overthrusted by the Lesser
Himalaya along the Main Boundary Thrust (MBT) and subsequently they themselves
are thrust south-westwards over Holocene sediments of the Indus-Ganges plains by
the Main Frontal Thrust (MFT). As the Himalaya uplifted, sediment shed from the
growing mountains collected in a flexural foredeep to the south. These sediments
lithified and now form the Sub-Himalaya or Siwalik Group which are constituting
densely vegetated low-altitude foothills with an average altitude of 900-1500 m. The
Siwalik molasse basin was created by flexure of the Indian lithosphere below the load
of the southward advancing of thrust sheet, and consists of an about 5 km thick,
upward coarsening succession of fluvial siltstone, sandstone and conglomerate. As in
other parts of Sub-Himalayan zone of Pakistan and Nepal, Sub-Himalaya in NW-
Himalayan also comprises three informal units known as the lower, middle and upper
members on the basis of dominant rock types.
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1.2.1.2. Lesser Himalaya
The Lesser Himalaya shows alpine type mountain ranges with altitudes
ranging between 1500 to 5000 meters. The Lesser Himalaya is ~ 20 km thick pile of
predominantly Early Proterozoic to Lower Cenozoic low to medium grade
metasedimentary rocks with some Ordovician granite intrusion. In this zone inverted
metamorphism also occurs. These low-grade sediments are thrust over the Sub-
Himalaya along the Main Boundary Thrust (MBT) in the south and restricted from the
Higher Himalaya by the Main Central Thrust (MCT) in the north. In the NW-
Himalaya this zone is inhomogeneous and extensively wider particularly in the
Kumaun-Garhwal region whereas squeezed and form a narrow belt in the Himachal-
Kashmir area. Additionally, Lesser Himalayan lithologies can be found in large
tectonic windows below the Higher Himalaya, the Kishtwar Window (Fuchs, 1975;
Guntli, 1993) and the Kullu- Larji-Rampur Window (Frank et al.,1973; Thoni et al.,
2012) indicating a minimum thrusting distance of 100 km on the km thick Main
Central Thrust zone.
The lithologies range from Precambrian to Eocene with a major break in
deposition between middle Cambrian and Eocene, the metamorphic grade is generally
low, but can reach lower greenschist conditions in the uppermost nappes (Srikantia
and Bharaga, 1998). Within the Lesser Himalaya, several tectonic units can be
distinguished, in principal several nappes are thrust above nearly unmetamorphosed,
imbricated, para-autochthonous sedimentary series (Frank et al., 1995; Srikantia and
Bhargava, 1998; Valdiya,1998).
Four successive para-autochthonous Proterozoic sedimentary megacycles,
bordered by unconformities, have been distinguished in the Lesser Himalaya: (Virdi
1995, Srikantia & Bhargava, 1998) (i) Rampur-Berinag cycle (1800 Ma; Miller, et al.
2000) consists of striking ortho- quartzites and slates associated with basic volcanics
(ii) Shali (= Larji = Deoban) cycle (1400-900 Ma) comprises dolomitic and calcareous
stromatolites with very rare siliciclastics (iii) Shimla cycle (900-700 Ma) consists of
shales and greywackes with minor carbonates and rare volcanics and the cycle ends
with redbeds (Nagthat Fm.) (iv) Blaini-Krol-Tal cycle (700 Ma to early Cambrian)
shows two diamictite horizons (Blaini Group) followed by black shales and
carbonates and finally succeeded by dolomites with some siliciclastics.
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1.2.1.3. Higher Himalaya (Greater Himalayan Crystalline Complex)
The Higher Himalaya forms the backbone of the Himalayan orogen and
encompasses the areas with the highest topographical relief. More or less, 30 different
names exist in the literature to describe this zone; however, the most frequently
establish equivalents are the Higher Himalayan Crystalline, Greater Himalayan
Sequence, and Tibetan Slab. The Greater Himalayan rock is separated from the
structurally overlying Tibetan Himalayan zone by the South Tibetan Detachment
system (STDS), which is a series of brittle-ductile normal faults. The base of the
Greater Himalayan rock is thrust over the rock of the Lesser Himalayan unit along the
MCT.
The Higher Himalayas comprised of ductily deformed metamorphic rocks and
marks the axis of orogenic uplift. In the NW-Himalayan region, the Higher Himalaya
is mainly composed of an approximately 10-30 km thick sequence of medium-to
high-grade metamorphic and metasedimentary rocks particularly various gneisses,
schist, quartzite and marbles which are frequently intruded by granites of Ordovician
(~500 Ma) and Lower Miocene (~22 Ma) age (Thakur, 1987; Dezes, 1999).
Deformation seems to have occurred in a north to south direction and is associated
with the MCT which brings the Higher Himalayas on top of the lower Himalayas
(Sorkhabi and Macfarlane, 1999). According to Windley (1995), approximately
350km of shortening had occurred in the Greater Himalayan sequence of rocks.
However, through studies by DeCelles et al., (1998), a major thrust fault within the
zone was discovered and estimated that between 600 and 650km of shortening may
have occurred in this unit. The Higher Himalayan sequence is wider in western part
especially in the Kashmir-Kistwar region and much narrow in eastern side around the
Kumaun-Garhwal vicinity.
1.2.1.4. Tethys Himalaya
The Tethys Himalayan sedimentary zone is one of the major tectonic domains
within the Himalaya (Gansser, 1964; Le Fort, 1996; Hodges, 2000; Yin, 2006),
stretching for about 1500 km from Zanskar (NW India) to south Tibet (SW China).
The Tethys Himalaya is ~100 km large synclinorium and ~12 km thick pile that is
formed by strongly folded and imbricated, sedimentary and weakly metamorphosed
rocks especially, shale, phyllites, limestones and quartzose sandstones of the
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Cambrian to Eocene age (Searle, 1986). Some basalts are also widespread in the
Tibetan sedimentary sequences of the Zanskar and the Kashmir region (Hodges,
2000). Its northern boundary coincides with the Indus-Tsangpo Suture (Gansser,
1983), whereas the southern boundary is represented by the tectonic contact with the
High Himalaya Crystallines (HHC), commonly referred to as South Tibetan
Detachment System (STDS; Burg et al., 1984; Herren,1987; Burchfiel et al., 1992;
Searle and Godin, 2003) and preserves a continuous stratigraphic record for over 500
Ma documenting the history of northern Gondwana during most of the Phanerozoic
(Gaetani and Garzanti, 1991; Brookfield,1993). The Tethys Himalayan zone can be
divided into four subsequences, (1) Proterozoic to Devonian pre-rift sequence
characterized by laterally persistent lithologic units deposited in an epicratonal
setting, (2) Carboniferous to Lower Jurassic rift and post-rift sequence which shows
dramatic northward changes in thickness and lithofacies, (3) Jurassic–Cretaceous
passive continental margin sequenc and (4) upper most Cretaceous–Eocene
syncollision sequence (Liu and Einsele, 1994; Garzanti, 1999; Myrow et al., 2010;
Sciunnach and Garzanti, 2012).
The Himalayan orogen, along strike, may be divided into the western (66o–
81o), central (81o–89 o), and eastern (89o–98o) segments. The western Himalayan
orogen covers the following regions which mostly appear in the literature; Salt Range
in northern Pakistan, Kashmir (also known as the Jammu and Kashmir State of NW
India), Zanskar, Spiti, Chamba, Himachal Pradesh, Lahul, Garhwal, and Kumaun
(also spelled as Kumaon). The central Himalayan orogen includes Nepal, Sikkim, and
south-central Tibet, whereas the eastern Himalayan orogen occupies Bhutan,
Arunachal Pradesh of NE India, and southeastern Tibet.
A systematic change along-strike in the Himalayan topography is mainly
expressed by the geometrical differences or variations of the modern intermontane
basins in the South Himalaya. For instance, the intermontane basins with north–south
widths >80–100 km are situated in northern Pakistan (e.g., Jalalabad and Peshawar
basins) and Kashmir (Kashmir basin) in western Himalaya(Fig.1.4). However,
intermontane basins shows more elongated and narrower geometry (<30–40 km in
width from north–south) in the central Himalayan orogen and are completely absent
in the eastern Himalaya. This variation may be a direct result of an eastward increase
in the total crustal shortening along the Himalayan orogen (Yin, 2006).
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Fig.1.4. Regional geologic map showing location of Kashmir Basin by sold red ellipse in the Himalayan orogen. Main sources are from Liu, (1988), Frank et al., (1995), Fuchs and Linner, (1995); Yin and Harrison, (2000), Ding et al., (2001), DiPietro and Pogue, (2004) and Yin, (2006).
1.3. Kashmir Basin
The Kashmir Basin (Fig.1.4 solid red ellipse and Fig.1.5) is a northwest--
southeast, elongate depression about 140 km long and up to 60 km wide. Kashmir
Basin has the morphological characteristics of an intermontane basin and is located on
a nearly horizontal nappe sheet (Wadia, 1976). Kashmir Basin occupies the
depression formed by the bifurcation of the Great Himalayan Range whose south-
western arm is known as the Pir-Panjal Range and the north-eastern arm as the Main
Himalayan Range. The location of the Valley at a high altitude in the northwest nook
of the sub-continent, and enclosed within high mountain ranges, gives it a distinctive
character with its own climatic peculiarities. Within the Valley, interesting variations
in weather are witnessed, largely owing to the variations in the altitude and aspect
(Arthur Neve, 1933). It is difficult to classify the Valley of Kashmir in a specific
climatic regime as sharp variations are observed from year to year. Meher-Homji,
(1971), established that the climate of the Valley swings between temperate to sub-
Mediterranean in all its variants. The Jehlum River and a host of streams that drain the
bordering mountain slopes together constitute the drainage network of Intermontane
Kashmir Basin.
Intermontane Basins
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Fig.1.5. Three dimensional (3D) view of Intermontane Kashmir Basin situated in NW Himalaya.
1.4. Aim and Objective of the Research
The present study will be carried out with a principal objective to generate as
much as possible updated structural account of the rocks of the area and it’s adjoining
with emphasis on to the analysis of the structural and tectonic features of the region in
relation to the regional tectonics, its kinematic, dynamic and tectonic implications.
The structural features of the area would be analyzed to reconstruct the paleostress
orientation in the area. Drainage analysis will be done as it generally provides
evidence to structural features and lithological variation, supported by the structural
lineament analysis and field investigations. Thus, the role of rock types and geologic
structure in the development of stream networks can be better understood by studying
the nature and type of drainage pattern and by the quantitative different drainage
parameters. The morphometric analysis would help in assessing the area most affected
by floods and soil erosion hazards. The area has been selected for detailed
morphotectonic and morphometric studies with the help of GIS and high resolution
remote sensing data to analyze the generated data for interpreting the effects of the
neotectonism in the area particularly on the fluvial systems in order to locate
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structures possibly of active nature vulnerable to earthquakes. Various types of
structures present in different lithology in the area are analyzed separately in relation
to the regional tectonics. Remote sensing techniques and field investigations would be
carried out to find the relation between drainage network, geomorphic indices and
different features; in identifying the area more influenced by tectonic activity.
Different rock types with associated structures like folds, faults, fractures/joints and
soft sediment deformation structure investigation would help in understanding their
origin and development in relation to Himalayan tectonics. The past earthquake with
their depth and time constraint and particularly their spatial and temporal distribution
of the epicenters would help in analyzing the relative activeness of tectonic features
responsible for their occurrence. Historical records of seismicity including damaging
earthquakes in 1555, 1885 and 2005 in and around Kashmir Basin, give an idea about
the active deformation in Kashmir basin and its surroundings. The presence of
lithology (Karewas) susceptible to liquefaction and soft sediment deformation
structures would help to investigate the past seismic behavior of the area. The
correlation of earthquake epicenters and tectonic lineaments would help out to assess
the seismic hazard and other natural disasters.
1.5. Scientific Benefits
The proposed study would help to assess the geometry, resultant of
lithological variation and presence of structural features in the area. The
morphotectonic and morphometric analysis jointly be applied to infer the
tectonic, erosion risk and flood behaviour of the area. The investigation of
structural features both in hard rock (mesoscopic folds, faults, joints/fractures
and others) and in soft rocks (soft-sediment deformation structures) would help
in understanding their origin and development and interpret the effect of different
tectonic phases of Himalayan deformation. Investigation of seismites and
paleoseismicity would help in the assessment of seismic behaviour of the region
in the past and its future earthquake scenario. Investigations using remote sensing
techniques for calculation of geomorphic indices and field verification would help
to delineate tectonically active structures (faults) which can be the source of
earthquakes in the area. Investigation of mesoscopic structures in hard rock’s
would help to locate the paleostress direction and possible stage of deformation
in the Kashmir basin.