JAPRS & SIS, Vol.34, Part 7, “Resource and Environmental Monitoring”, Hyderabad, India, 2002 
  
STRUCTURAL ANALYSIS OF LINEAMENTS USING REMOTE SENSING 
TECHNIQUES IN A PART OF LESSER GARHWAL HIMALAYA, TEHRI- 
UTTARKASHI DISTRICTS 
Arvind.C.Pandey®, Chandra.S.Dubey” 
"Haryana State Council for Science & Technology, Chandigarh. email: arvindchandrap yahoo.com 
"Department of Geology, University of Delhi, Delhi-110007 
  
KEY WORDS: Lineaments, Garhwal Himalaya, Thrust, Faults, Joints, Satellite Image 
ABSTRACT: 
Himalayan Mountain was formed due to continent-to-continent collision during the Tertiary period. Post collision deformation and 
tectonics resulted in the development of lineaments, parallel and transverse to the Himalayan trend. In the present study lineament 
mapping was done in the area on 1:50,000 scale using IRS-IC, geocoded False Colour Composite (FCC) images of October 1996. 
Based on the litho-tectonic setting of the area, the lineaments are present in Krol block (slate-limestone-quartzite formations), 
Chandpur block (phyllite), Pratapnagar block (quartzite) and Crystalline block (gneisses & schist). Each of the blocks is 
separated from the adjacent block by a major thrust of regional extent. The lineament distribution in the study area indicates 
four prominent trends with a total number of 1096 lineaments. These are N55°E-S55°W, N50°W-S50°E, N90°E-S90°W and 
N10°E-S10°W. It is to state that these groups were closely linked with thrusts, faults, joints and anticlinal/synclinal axes. 
The rocks of Tehri-Uttarkashi area experienced four phases of deformation during the Himalayan orogeny. In sequence to 
these phases of folding, the thrusting of rocks of the Central Crystallines, Pratapnagar, Chandpur and Krol groups took 
place, which was accompanied by transverse faulting. The joints were also developed in conjugate sets during the folding 
episodes. The origin of these lineaments can be ascribed to tectonic forces, which caused various phases of folding and 
tectonics in the region. The satellite images proved highly useful in delineation of lineaments which coupled with ground 
based information on kinematics of minor and major structures provided meaningful insights into the tectonic evolution 
of the area. 
1.4 INTRODUCTION caused by structural and geomorphic features or by tonal 
contrast. Continent to continent collision in the Himalayas is 
well known. Post collision deformation and tectonics 
resulted in the development of lineaments, parallel and 
transverse to the Himalayan trend. Some of these lineaments 
are also seismically active (Khattri, et al. 1989). The Tehri- 
Uttarkashi region of Garhwal Himalaya is characterised by a 
large number of lineaments, which represent regional joint 
patterns, major fractures, anticlinal or synclinal fold axes as 
well as faults. The lineaments are rectilinear or curvilinear 
depending on the inclination of structural plane. 
The area under investigation lies in the Tehri and Uttarkashi 
districts, (Garhwal) of Uttaranchal State bounded by 78?15' — 
78°45' east longitude and 30°15' — 30°50" north latitude covering 
an area of about 2700 square kilometer. The Garhwal Himalaya 
structurally consists of superposed and imbricated nappes, 
which are delineated at their base by well-defined thrusts. In the 
present study the author has attempted the delineation of 
lineaments on the satellite images to deduce their relationship 
with the tectonics in the region. 
The study area is constituted by a number of nappes, namely, 
the Krol, Chail (I, II, III) and Crystalline nappes (I, II, III). Each 
of the nappes is characterized by a distinct lithology and 
1.3 METHODOLOGY 
  
metamorphism. Based on the field investigations and satellite 
image interpretation, the thrusts of regional extent viz; Garhwal 
thrust, North Almora thrust (NAT), Pratapnagar thrust, 
Bhudhakedar thrust (Main Central thrust-III) and Jutogh thrust 
(Main Central thrust-II) were delineated in the area. These 
thrusts of regional extent show NW-SE trend with northeasterly 
dips varying 25°-45°, except for the North Almora thrust which 
dips in south. 
1.2 LINEAMENT ANALYSIS 
Lineament is simple or composite linear feature on the earth 
surface with a subsurface extension. It is either straight or 
curved. The surface features demarcating the lineaments can be 
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In the present study lineament mapping was attempted in the 
area on 1:50,000 scale using IRS-IC, geocoded False Colour 
Composite images of October 1996. Lineaments are well 
expressed on IRS images because of low sun angle, the 
suppression of distracting spatial details, and the regional 
coverage. The IRS-IC, geocoded FCC images because of their 
better spatial resolution (23.5m) and large scale (1:50,000) help 
in accurate mapping of lineaments as compared to black and 
white LANDSAT images of 1:250,000 scale. The lineaments 
are demarcated on the satellite images using standard photo 
interpretation technique of lineament mapping. These 
lineaments are then transferred on tracing sheets for statistical 
analysis of lineaments. Virdi (1979), Bharktya. and Gupta 
(1982) utilised the black and white LANDSAT images of 
1:250,000 scale, who mainly focussed on the regional 
distribution of mega lineaments.