Accepted Manuscript

Slope stability analysis of Balia Nala , Kumaun Lesser Himalaya, , ,

Mohit Kumar, Shruti Rana, Pitamber Dutt Pant, Ramesh Chandra Patel

PII: S1674-7755(16)30218-9 DOI: 10.1016/j.jrmge.2016.05.009 Reference: JRMGE 291

To appear in: Journal of Rock Mechanics and Geotechnical Engineering

Received Date: 16 January 2016 Revised Date: 26 April 2016 Accepted Date: 17 May 2016

Please cite this article as: Kumar M, Rana S, Pant PD, Chandra Patel R, Slope stability analysis of Balia Nala landslide, Kumaun Lesser Himalaya, Nainital, Uttarakhand, India, Journal of Rock Mechanics and Geotechnical Engineering (2016), doi: 10.1016/j.jrmge.2016.05.009.

This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. ACCEPTED MANUSCRIPT Slope stability analysis of Balia Nala landslide, Kumaun Lesser Himalaya, Nainital, Uttarakhand, India

Mohit Kumar a,*, Shruti Rana a, Pitamber Dutt Pant a, Ramesh Chandra Patel b a Department of Geology, Kumaun University, Nainital, India b Department of Geophysics, Kurukshetra University, Kurukshetra, India Received 16 January 2016; received in revised form 26 April 2016; accepted 17 May 2016

Abstract: Balia Nala is the outlet of the , flowing towards southeast direction. Presence of Nainital habitation at its right bank has high socio-economic importance. This study presents the stability analysis of a ravine/valley along Balia Nala. Variegated slates (lower Krol and upper Blaini formations) are the main rock types, wherever the outcrop does exist and rest of the area is covered by slope wash and river borne materials. Three sets of joints are presented in the area, but 4 sets of joints also exist at some locations. Nainital lake fault intersected by Manora fault from southwest direction passes through eastern side of the study area, and some small faults, which are sub-branches of Nainital lake fault, are observed (with 10 m offset) and promote the landslide in the area. This study shows that different kinds of discontinuities (joints, faults and shear zones) and rapid down cutting by the stream due to neotectonic activity affect the stability of the slope. The fragile lithology and deep V-shaped valley further accelerate the mass movement in the study area. In addition, rock mass rating (RMR), factor of safety (FOS) and graphical analysis of the joints indicate the study area as landslide-prone zone. This study will be helpful in not only reducing the risk on life of people, but also in assisting the ongoing civil work in the study area. Keywords: rock mass rating (RMR); factor of safety (FOS); Balia Nala landslide; slope stability analysis

composed of pyriteous slates of Kailakhan member (Infra Krol), slates of 1. Introduction Manora member (calcareous slates, greyish to greenish in color), purple slates of Hanumangarhi member (ferruginous slates), and dolomite blocks Slope failure may lead to loss of lives, property and environmental of Pashandevi member (Valdiya, 1988). In Balia ravine near Tallital of degradation. In the Himalayan region, slope instability (Panikkar and Nainital hills, the major lithologies are crumpled Kailakhan slate Subramanyam, 1997), tectonic activity and mass movement frequently (pyritiferous slates of Infra Krol) and lower Krol slate. occur due to steep slopes (Paul and Mahajan, 1999), and highly sheared, The study area is bound by the MBT in the south along which the LHS crushed and deformed rocks. In the southern margin of Kumaun sub- has thrust over the sub-Himalaya (Fig. 1). The MBT is characterized by Himalaya, the frequency of is high due to structural and imbricating thrusts and faults (Valdiya, 1984). It influences the active neotectonic activities along the main boundary thrust (MBT) zone tectonic movements in this area. Other major faults in this area are (Valdiya and Bartariya, 1989; Valdiya, 2001, 2003). In the past two NainitalMANUSCRIPT lake fault (Middlemiss, 1890) and Manora fault (Valdiya, 1988) decades, Malpa rockfall in 1998 (Pant and Luirei, 1999), Okhimath (Fig. 1). The Nainital lake fault passes through the Nainital lake and landslide along Mandakini valley in 1998 (Sah and Bist, 1998), Amiya rotational movement along this NW-SE trending lake fault is described as landslide of southern Kumaun (Pant and Luirei, 2005), Phata Byung the mechanism of development of the Nainital lake. The landslide of Rudraparyag district in 2001 (Naithani et al., 2002; thermoluminescence dating of neotectonic events as recorded in fault Chaudhary et al., 2010), Budha Kedar landslide in Balganga valley (Sah gages and buried soils formed on landslide debris related to the lake fault et al., 2003), Varunawat landslide in 2003 (Gupta and Bist, 2004), indicates that the Nainital lake was formed at calibrated annum 40 −50 ka Agastyamuni landslide in 2005 (Rautela and Pande, 2005), natural (Singhvi et al., 1994). The eastern ridge, named as Sher-Ka-Dada, is the hazards in Alaknanda valley (Joshi and Kumar, 2006), landslide in up thrown block exposing the lower Krol , whereas the western Pitthoragarh district in 2009 (Sarkar and Kanungo, 2010), and landslide in block (Ayarpatta ridge) is down thrown block exposing the upper Krol Asi in 2012 (Gupta et al., 2013; Martha and Kumar, 2013) have succession. This fault has dextrally offset the MBT near Beluakhan west devastatingly affected Uttarakhand, India. of Jeolikot (Valdiya, 1984) and Manora fault near Alukhet (Fig. 1). Nainital is a popular hill station in the Indian state of Uttarakhand and Development of Balia Nala is related to movements along the Nainital headquarter of in the Kumaun foothills of the outer lake fault oriented obliquely or transversely to the regional trend of Himalaya. The slopes of the nearby mountains are most populated, with orographic arc. The drainage is trellis type considerably sharpened and an elevation ranging from 1940 m to 2100 m. To prevent and/or reduce suitably modified by neotectonic tear faults (Valdiya, 1988). Drainage the landslide hazards, stability analysis has been carried out in this area density is high due to softness of the rocks (Valdiya, 1988). (Fig. 1). ACCEPTED3. Study area 2. Geology and tectonic setup

The geological setting of the Kumaun Himalaya has been studied in details by many scholars (e.g. Auden, 1934; Heim and Gansser, 1939; Fuchs and Sinha, 1974; Hukku et al., 1974; Pal and Merh, 1974; Pande, 1974; Valdiya, 1980). Nainital hills, the area of study, represent the outer sequence of the lesser Himalayan sequence (LHS). It is the southeastern part of a strip of en echelon basins of the Krol belt. The study area is

*Corresponding author. E-mail address: [email protected] ACCEPTED MANUSCRIPT

Fig. 1. Geological and location map of the study area (Valdiya, 1988).

The study area stretches 2.1 km along the Balia Nala and is delineated by 29 °22 ′E−29 °21 ′E latitude and 79 °28 ′N−79 °28 ′23.2 ″ longitude 4. Methodology (towards southwest of Nainital, Fig. 1). The elevation ranges from 1450 m to 1920 m. The right bank of this stream has two populated localities, i.e. Geological and engineering geological mapping has been carried out in (a) locality nearby Government Inter College (GIC) and (b) Saraswati theMANUSCRIPT study area on 1:1000 scale (Fig. 3a and b). Geological cross-sections ′ ′ ′ Vihar, both affected by landslides. have been plotted in Fig. 4 along four section lines (1-1 , 2-2 , 3-3 and 4- 4′) marked in Fig. 3. This work has focused on the rock mass characterization by rock mass rating (RMR), factor of safety (FOS) and kinematics analysis (stereographic projection) of the discontinuities. RMR has wide application in tunnels, slopes, foundations and mines (Bieniawski, 1989). In rock mass classification system, methodology is proposed to identify the quantitative condition of road slope. It is broadly used in underground rock tunnels and road cut slopes. RMR also plays a key role in calculation of the slope mass rating. RMR includes the collection of field data, i.e. orientations of different discontinuities, uniaxial compressive strength (UCS) (measured using Schmidt hammer according to ISRM (1978, 1981, 2007), Bieniawski (1989), and Brencich et al. (2013)), spacing, slope direction and dip, conditions of discontinuities and groundwater conditions. Rock quality designation (RQD) has been calculated according to Singh and Goel (1999) in the

field. RQD is calculated using number of joints per unit volume Jv and

equal to 115 −3.3 Jv. FOS has been calculated for every outcrop according ACCEPTEDto Hoek and Bray (1981). FOS of a rock slope is the ratio of resisting forces to driving forces. If FOS is less than or equal to 1, the slope will fail. If FOS is much larger than 1, the slope will be quite stable. However,

Fig. 2. Average monthly and annual rainfall during 2007 −2013 (Source: Aryabhata if the FOS is slightly greater than 1, small disturbance may cause the Research Institute of Observational Science, Nainital). slope to fail (Hoek and Bray, 1981). To analyze various modes of rock slope failures (plane, wedge, and toppling failures), Markland’s test has been performed as described by Hoek and Bray (1981). Various modes of Annual rainfall recorded in this area is 2468 mm during 1995 −2009, failures have occurred due to presence of unfavorable oriented while it is 4190 mm during 2007 −2013 (Fig. 2). The recorded rainfall discontinuities (Hoek, 2007). Kinematics refers to the motion of bodies shows 70% increase (Gupta et al., 2015). Each monsoon triggers slope without reference to the forces that causes them to move (Goodman, instability, as more than 80% of slope along Balia Nala is composed of 1989). It is one of the most useful techniques in the recent years to argillaceous rocks (slates) (Fig. 3a). ACCEPTED MANUSCRIPT investigate possible failure modes of rock masses which contain discontinuities (Hussain et al., 2015).

Fig. 3. Geological map (a) and engineering geological map (b) of the study area with four cross-sections (1-1′, 2-2′, 3-3′ and 4-4′).

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Fig. 4. Geological cross-sections (1-1′, 2-2′, 3-3′ and 4-4′) along the marked section lines in Fig. 3.

FOS for wedge failure of slope can be calculated by ACCEPTED MANUSCRIPT 1 Hanumangarhi member (reddish color), as shown in Fig. 3a. This rock has F = sinβ tan φ (1) sin(ξ / 2)tan ϕ weak to very weak strength. Other rock types in the area include dolomite where β is the angle between intersection line of discontinuity and the of Pashandevi member which is compact with high strength, and marl. bisector, φ is the friction angle, ξ is the wedge angle, and ϕ is the plunge Engineering geological map (Fig. 3b) shows that most of the area is of intersection line of two discontinuities. covered by slope wash and river born materials, and at few localities, FOS for planar failure of slope can be calculated by slates, dolomite and Tal formation rocks are exposed as pinching and FcAW=+[ ( cosψ −− UV sin ψφ )tan]/( W sin ψ + V cos ψ ) (2) swelling shape on the surface. Most of the rock mass is highly deformed where c is the cohesion, A is the area of the block, W is the weight of and dissected by 3 −4 sets of joints (Fig. 5a). − sliding block, U is the uplift force due to water pressure on sliding Nainital lake fault has been described to develop during 40 50 ka surface, V is the force due to water pressure in tensile crack, and ψ is the (Singhvi et al., 1994) with a movement rate of 6 cm per year (Kotliya et dip of failure plane. al., 2009). This study indicates that the Nainital lake fault is a result of neotectonic activities in this area. Most prominent evidence is the rapid 5. Results and discussion down cutting along the course of Balia Nala. At locations 7 and 10 (Fig. 3a), two subsidiary faults of the Nainital lake fault are identified along During mapping, many structural features have been documented. which ~10 m lithological offset (Fig. 5b) of dextral sense has occurred − Predominant rock type presented in the area is slate of Manora member (Fig. 5c). Waterfalls of 0.5 0.7 m in height (Fig. 5d) are also (greenish color), Kailakhan member (grey to dark grey color) and characteristic features presented along these faults.

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Fig. 5. (a) Four sets of joints in the carbonaceous slate. (b) A dextral strike slip fault along the stream with 10 m offset. (c) Shear sense indicator showing dextral movement. (d) 0.5 −0.7 m high waterfall along the stream. (e) GIC ground showing 0.5 m subsidence. (f) Toppling failure at the right bank of the stream. (g) Cracks in the houses at the right bank. (h) Tensile cracks presented nearby GIC ground. All the geological cross-sections drawn in this area show the orientation and distribution of the discontinuities in the area. In this area, relationship between slope and discontinuities. The L-section of the area slope is steep (>60°) (Table 1). It has resulted in 5−10 m thick slope wash (Section 1-1′ in Fig. 4) shows the gradient of the stream and the material (Sections 2-2′, 3-3′and 4-4′). Section 2-2′ in Fig. 4 shows that the ACCEPTED MANUSCRIPT dip of joint J1 (64°) is steeper than that of the slope. Argillaceous slate is surface with 0.1 −0.3 m wide and 2 −3.3 m deep (Fig. 5h). Our surface data exposed along the course of the stream and dolomite is exposed at the top show that the GIC ground has 5 −10 m thick overburden below which of it. The slates along the course of stream are eroded rapidly. Due to there are tensile cracks (Section 2-2′ in Fig. 4). However, ground these and neotectonic activities in the area (Kotliya et al., 2009), the rocks penetrating radar (GPR) data (Gupta et al., 2015) also confirmed our at the right bank slide downward due to which toppling failure and observation on GIC. At the left bank, Kelakhan slate underlies the subsidence (0.5 −1.5 m) of ground are common at GIC ground (Fig. 5e Manora slate. Joint J2 presented in these rocks dips 58 °−78° towards and f). It is supported by various evidences such as tilting of poles and valley, which accelerates the slope failure (L-27 in Fig. 6). ground (Fig. 5e), cracks in the houses (Fig. 5g) and tensile cracks on the

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Fig. 6. Stereographic projection for different locations (L-13, L-14, L-16, L-17, L-27 and L-29) with respect to presented discontinuities, slope and river trend.

Section 3-3′ shows that, at the right bank, there is no planar and wedge At this section, discontinuities J0, J1 and J2 form wedge (L-7 in Fig. 7) formations (L-16 and L-17 in Fig. 6). At this location, Saraswati Vihar and planar failures (L-7 and L-8 in Fig. 7). colony is situated. At the left bank, location L-12 (Fig. 7) is stable, but RMR was calculated on the basis of various parameters. RMR value away from the river bed, discontinuities J1 and J2 form the wedge which ranges from 36 to 55 for the locations L-7, L-8 and L-13, whereas it has plunge of 266 °/49 ° towards valley (L-29 in Fig. 6). Section 4-4′ ranges from 46 to 60 at locations L-1, L-2, L-6, L-7 and L-29. Based on shows that the thickness of slope wash material varies from 10 m to 15 m. the RMR classification, rocks of this area fall into poor to fair class (Table 1).

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Fig. 7. Stereographic projection for different locations (L-1, L-2, L-6, L-7, L-8, L-10, L-11 and L-12) with respect to presented discontinuities, slope and river trend. L-7 (right Table 1. Final results of this study. bank Slope Rock RMR slope) Slate 60 72.2 55-56 Fair Planar failure J2 0.06 Location angle RQD (%) RMR Failure type Responsible type class L-8 Slate 60 78.8 52-57 Fair Planar failure J1 0.4 (°) discontinuity FOS L-9 Slate 60 72.2 50-54 Fair L-1 Slate 60 65.5 54 Fair Wedge failure J1, J2 -0.29 L-10 Slate 60 58.9 59-60 Fair L-2 Slate 60 65.5 52-57 Fair Wedge failure J1, J2 0.012 Stable L-11 Slate 60 72.2 56-61 Fair L-6 Slate 60 45.7 59-60 Fair Wedge failure J0, J1 -0.16 L-12 Slate 60 72.2 52 Fair L-7 (left L-13 Slate 60 49 36-37 Poor Planar failure J1 0.12 bank L-14 Slate 60 52.3 40 Poor slope) Slate 60 72.2 55-56 Fair Wedge failure J1, J3 0.02 Stable L-16,17 Slate 60 49 50-52 Fair ACCEPTED MANUSCRIPT L-27 Slate 60 45 51-53 Fair Auden JB. Geology of the Krol belt. Records of the Geological Survey of India 1934; L-29 Slate 60 42.4 46-47 Poor Wedge failure J1, J2 0.03 67:357-454.

Bieniawski ZT. Engineering rock mass classification. New York: John Wiley and Sons, Stereographic projection analysis has been carried out to understand the Inc., 1989. kinematics based on the Markland’s test and using internal friction angle Brencich A, Cassini G, Pera D, Riotto G. Calibration and reliability of the rebound and relative slope direction/dip of discontinuities. Kinematics analyses of (Schmidt) hammer test. Civil Engineering and Architecture 2013; 1(3):66-78. slope at locations L-1, L-2, L-6, L-7, L-8, L-13 and L-29 (Figs. 3, 6 and Chaudhary S, Gupta V, Sundriyal YP. Surface and sub-surface characterization of Byung 7) show that these locations are structurally controlled and not safe for the landslide in Mandakini valley, Garhwal Himalaya. Himalayan Geology 2010; 31(2): construction. Totally 15 locations are analyzed for wedge and planar 125-32. failures (Table 1, Figs. 6 and 7). Out of 15 investigated sites, 8 sites Fuchs G, Sinha AK. On the geology of Nainital (Kumaun Himalaya). Himalayan Geology (53.33%) are unstable. Internal friction angle of 25° and cohesion of 40 1974; 4:563-80. kPa are taken for slate according to Hoek and Bray (1981). Both the dry Goodman RE. Introduction to rock mechanics. New York: Wiley, 1989. and wet conditions have been considered during the FOS calculation. Gupta V, Bist KS. The 23 September 2003 Varunavat Parvat landslide in Uttaranchal FOS is smaller than 1 for the landslide-prone sites (Table 1). township, Uttaranchal. Current Science 2004; 87(11): 1600-5. Stereographic projection of discontinuities confirms the wedge and planar Gupta V, Dobhal DP, Vaideswaran SC. August 2012 cloudburst and subsequent flash flood failures in the study area (Figs. 6 and 7). At the left bank, wedge failures in the Asi Ganga, a tributary of the , Garhwal Himalaya, India. Current have 285°/50° (L-7 in Fig. 7) and 266°/49° (L-29 in Fig. 6) trend and Science 2013; 105(2): 249-53. plunge with FOS of 0.02 and 0.03, respectively. Rocks at these locations Gupta V, Bhasin RK, Kaynia AM, Tandon RS, Venkateshwarlu B. Landslide hazard in the belong to class III (Table 1). Similarly, at the right bank, wedge failure Nainital township, Kumaun Himalaya, India: the case of September 2014 Balia Nala has 85°/30° (L-2 in Fig. 7), 34°/43° (L-6 in Fig. 7) and 99°/39° (L-1 in landslide. Natural Hazards 2015; 80(2): 863-77. Fig. 7) trend and plunge with FOS of 0.012, 0.16 and 0.29, respectively. Heim A, Gansser A. Central Himalaya: Geological observations of the Swiss Expedition in Planar failure also shows FOS<1 (Table 1) at locations L-7, L-8 and L-13 1936. Zurich: Gebruder Fretz, 1939. (Figs. 6 and 7). On average, the study area receives 2000 mm rainfall per Hoek E, Bray J. Rock slope engineering. Hertford: Stephen Austin and Sons, Ltd., 1981. year during 2007 −2013 (Fig. 2). Rainfall is a paramount factor which Hoek E. Practical rock engineering. 2007. https://www.rockscience.com/ influences chemical weathering. It controls the supply of moisture for documents/hoek/corner/practical-Rock-Engineering-Full-Text.pdf. chemical reactions and for the removal of soluble constituents of the Hukku BM, Srivastava AK, Jaitle GN. Evolution of lakes around Nainital and the problem minerals. In the study area, the average overburden thickness is 10 −15 m of hillside instability. Himalayan Geology 1974; 4:516-31. (Fig. 5). So percolates into the surface and increases the pore water Hussain G, Singh Y, Bhat GM. Geotechnical investigation of slopes along the National Highway (NH-1D) from Kargil to Leh, Jammu and Kashmir (India). Geomaterials pressure which promotes the failure along the discontinuity planes (Hoek 2015; 5: 56-67. and Bray, 1981). The rain acts as lubricant along discontinuity surfaces, International Society for Rock Mechanics (ISRM). Suggested methods for the quantitative and facilitates the process of rock sliding. In soil (slope wash) slopes after description of discontinuities in a rock mass. International Journal of Rock Mechanics raining, the weight of soil mass increases and thus threatens the stability and Mining Sciences and Geomechanics Abstracts 1978; 15(6): 319-68. of the soil mass. Besides, groundwater helps to develop the pore water ISRM. Suggested methods for determining hardness and abrasiveness of rocks. In: Rock pressure within the soil mass which further aggravates the instability. MANUSCRIPT Characterization, Testing and Monitoring: ISRM Suggested Methods. Oxford: Therefore, the role of rainfall cannot be negligible in this area as it acts as Pergamon; 1981. pp. 95-6. lubricant for argillaceous sediments. ISRM. The complete ISRM suggested methods for rock characterization, testing and monitoring: 1974-2006. Springer, 2007. 6. Conclusions Joshi V, Kumar K. Extreme rainfall events and associated natural hazards in Alaknanda valley, Indian Himalayan region. Journal of Mountain Science 2006; 3: 228-36. − Along Balia Nala, the area has 3 4 joint sets. The RMR value obtained Kotliya BS, Joshi LM, Dumka RK, Kumar K. Vulnerability of the Balia Nala landslide at from the study area ranges from 36 to 61, representing poor to fair rock Nainital: Preliminary GPS analysis. In: Sah BL (ed). Natural Resources Conservation class. The highest RMR value is obtained from location L-11 and the in Uttarakhand. Haldwani: Ankit Publication; 2009. pp. 136-50. lowest from L-13. Kinematics analysis also reveals that most joint planes Martha TR, Kumar KV. September 2012 landslide events in Okhimath India: An intersect with each other and form different potential failures. Out of 15 assessment of landslide consequences using very high resolution satellite data. locations, 5 locations are susceptible to the wedge failure and 3 locations Landslides 2013; 10: 469-79. to plane failure. Finally, FOS calculated for the failure-prone locations Middlemiss CS. Geological sketch of Nainital with some remarks on the natural conditions ranges from 0.06 to 0.4 for plane failure and −0.29 to 0.03 for wedge governing the mountain slopes. Records of the Geological Survey of India 1890; 21: failure. 213-34. Naithani AK, Joshi V, Prashad C. Investigation on the impact of cloudburst in their district, Conflict of interest Uttaranchal-31 August 2001. Journal of Geological Society of India 2002; 60: 573-7. Pal D, Merh SS. Stratigraphy and structure of the Nainital area in Kumaun Himalaya. We wish to confirm that there are no known conflicts of interest Himalayan Geology 1974; 4: 547-62. ACCEPTEDPande IC. Tectonic interpretation of the geology of the Nainital area. Himalayan Geology associated with this publication and there has been no significant financial support for this work that could have influenced its outcome. 1974; 4: 532-46. Panikkar SV, Subramanyam V. Landslide hazard analysis of the area around Dehradun and Acknowledgements Mussorie, Uttar Pradesh. Current Science 1997; 73(12): 1117-23. Pant PD, Luirei K. Malpa rockfall of 18 August 1998 in the Northeastern Kumaun

Himalaya. Journal of the Geological Society of India 1999; 54(4): 415-20. The authors are thankful to Department of Geology, Kumaun Pant PD, Luirei K. Amiya landslide in the catchment of , Southern Kumaun, University at Nainital for necessary laboratory facilities. Uttarakhand. Journal of the Geological Society of India 2005; 65(3): 291-5.

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Mohit Kumar obtained a M.Sc. degree in applied geology from Kurukshetra University, Kurukshetra and is perusing PhD from Kumaun University, Nainital. He has two years’ experience in engineering geology and three years in academic as assistant professor in Kurukshetra University and guest faculty in Kumaun University, Nainital. He has been involved in geotechnical consulting for hydropower project and structural mapping project in Kedar valley. He is interested in engineering geology and structural geology.

Shruti Rana obtained a M.Sc. degree in geology from Kumaun University, Nainital and is perusing PhD from Kumaun University, Nainital. She is interested in geochemistry and tectonics.

Pitamber Dutt Pant obtained M.Sc. and PhD in geology from Kumaun University, Nainital and is professor in Department of Geology, Kumaun University, Nainital. He has published more than 30 research papers in national and international journals and is interested in landslide investigation, mitigation and structural geology. MANUSCRIPT

Ramesh Chandra Patel obtained M.Sc. and PhD in geology from Indian Institute of Technology and is professor in Department of Geophysics, Kurukshetra University, Kurukshetra. He has published more than 30 research papers in national and international journals (tectonics, techno physics, GSI) and is interested in low temperature thermochronology (fission track dating) and structural geology.

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