chapter-1 introduction - shodhgangashodhganga.inflibnet.ac.in/bitstream/10603/152653/9/08 chapter...

CHAPTER-1

Introduction

Chapter -1 Introduction

1

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.


6

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.

chapter-1 introduction - shodhgangashodhganga.inflibnet.ac.in/bitstream/10603/152653/9/08 chapter...

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