Wadia Institute Of Himalayan Geology Research Articles

Status of geo-scientific research at Wadia Institute of Himalayan Geology, Dehradun during 2020–2023

Status of geo-scientific research at Wadia Institute of Himalayan Geology, Dehradun during 2020–2023

Proceedings of the Annual General Meeting of the Geological Society of India–2022 held on 16.11.2022 at the Wadia Institute of Himalayan Geology, Dehradun

Proceedings of the Annual General Meeting of the Geological Society of India–2022 held on 16.11.2022 at the Wadia Institute of Himalayan Geology, Dehradun

Research Status at Wadia Institute of Himalayan Geology (WIHG), Dehradun during 2015 - 2019

The Wadia Institute of Himalayan Geology (WIHG) at Dehradun is an autonomous institution of the Department of Science & Technology (DST), GoI, which came into being in 1968. It has been pursuing basic researches to unravel the orogenic processes of majestic Himalaya and to provide improved understanding on seismogenesis, geodynamic processes, climate-tectonic interactions, evolution and extinction of life, ore formation, glaciology, river system, natural hazards (landslides, floods, and earthquakes), anthropogenic impact etc. towards the well-being of population and safeguarding the properties and structures in the Himalaya and adjoining regions. The research activities to understand the mountain building processes and shed light on above topics are based on observations made by using rudiments of structural geology, petrology, paleontology, stratigraphy, sedimentology, geomorphology, different branches of geophysics, remote sensing etc.

Call for Applications Wadia Institute of Himalayan Geology, Dehradun

Call for Applications Wadia Institute of Himalayan Geology, Dehradun

Wadia Institute of Himalayan Geology

Wadia Institute of Himalayan Geology

Frequency dependent attenuation characteristics of coda waves in the Northwestern Himalayan (India) region

Digital seismogram data of 82 earthquakes from the Northwestern Himalayan (India) region recorded at different stations during 2004–2006 were analyzed to study the seismic coda wave attenuation characteristics in this region. We used 132 seismic observations from local earthquakes with a hypocentral distance <240km and a magnitude range of 1.2–4.9 to study the coda QC using the single isotropic scattering model. These earthquakes were recorded at 20 temporary seismic stations installed in the Northwestern Himalayas (India) by the Wadia institute of Himalayan Geology, Dehradun. The QC values were estimated at 10 central frequencies: 1.5, 3, 5, 7, 9, 12, 16, 20, 24, and 28Hz using starting lapse-times of 10, 20, 30, 40, 50, and 60s and coda window-lengths of 10, 20, 30, 40, and 50s. The QC fits the frequency dependent power-law, QC=Q0fn. For a 10s lapse time with a 10-s coda window length QC=47.42f1.012 and for a 50s lapse time with a 50s coda window length, QC=204.1f0.934. Q0 (QC at 1Hz) varied from ∼47 for a 10s lapse time and a 10s window length, to ∼204 for a 50s lapse time and a 50s window length. An average frequency dependent power law fit for the study region may be given as QC=116.716f0.9943. The exponent of the frequency dependence law n ranged from 1.08 to 0.9, which correlates well with values obtained in other seismically and tectonically active and heterogeneous regions of the world. In our study region, QC increases both with respect to lapse time and frequency, i.e., the attenuation decreases as the quality factor is inversely proportional to attenuation. The low QC values or high attenuation at lower frequencies and high QC values or low attenuation at higher frequencies suggest that the heterogeneity decreases with increasing depth in our study region.

A study on the heavy rainfall event around Kedarnath area (Uttarakhand) on 16 June 2013

The heavy rainfall event during 14–17 June 2013 in Uttarakhand and more specifically, its occurrence around the Kedarnath region on 16 June 2013 with devastating floods and massive landslides ruined thousands of lives and properties. Increasing levels of water in two main rivers of the State, namely Alaknanda and Mandakini, resulted in the collapse of bridges, damaging and washing away of property worth many crores. In the present study, the advanced research version of the Weather Research and Forecasting (WRF) system (hereafter used as WRF model) is used to simulate this heavy rainfall event. The synoptic analysis at different locations such as Rudraprayag, Uttarkashi, Chamoli, Pauri, Tehri, Dehradun and adjoining districts suggested that the rainfall is about 200% more than normal. The rainfall associated with this event is well captured with the model simulation. The rainfall simulated by WRF model is in the range of 320–400 mm over Kedarnath during the actual occurrence of the event, which is in reasonably good agreement with the observed value of rainfall (325 mm) collected by Wadia Institute of Himalayan Geology.

Body Wave Crustal Attenuation Characteristics in the Garhwal Himalaya, India

We estimate frequency-dependent attenuation of P and S waves in Garhwal Himalaya using the extended coda normalization method for the central frequencies 1.5, 2, 3, 4, 6, 8, 10, 12, and 16 Hz, with earthquake hypocentral distance ranging from 27 to 200 km. Forty well-located local earthquake waveforms were used to study the seismic attenuation characteristics of the Garhwal Himalaya, India, as recorded by eight stations operated by Wadia Institute of Himalayan Geology, Dehradun, India, from 2007 to 2012. We find frequency-dependent P and S wave quality factors as defined by the relations Q P = 56 ± 8f 0.91±0.002 and Q S = 151 ± 8f 0.84±0.002 by fitting a power-law frequency dependence model for the estimated values over the whole region. Both the Q P and Q S values indicate strong attenuation in the crust of Garhwal Himalaya. The ratio of Q S/Q P > 1 obtained for the entire analyzed frequency range suggests that the scattering loss is due to a random and high degree of heterogeneities in the earth medium, playing an important role in seismic wave attenuation in the Himalayan crust.

Pilgrims, progress, and the political economy of disaster preparedness – the example of the 2013 Uttarakhand flood and Kedarnath disaster

Alan D. Ziegler,* Robert J. Wasson, Alok Bhardwaj, Y. P. Sundriyal, S. P. Sati, Navin Juyal, Vinod Nautiyal, Pradeep Srivastava, Jamie Gillen and Udisha Saklani 1 National University of Singapore, Geography Department, Singapore 2 Institute of Water Policy in the Lee Kuan Yew School of Public Policy, National University of Singapore, Singapore 3 Department of Geology, HNB Garhwal University, Srinagar Garhwal, Uttarakhand, India 4 Physical Research Laboratory, Navrangpura, Ahmedabad, India 5 Department of Ancient History and Archaeology, HNB Garhwal University, Srinagar-Garhwal, Uttarakhand, India 6 Wadia Institute of Himalayan Geology, Dehra Dun, Uttarakand, India

WIHG Winter School in Geomathematics Sponsored by Science &amp; Engineering Research Board (SERB) DST, Government of India 16–30 December 2013 at Wadia Institute of Himalayan Geology (An Autonomous Institution of DST, Govt. of India), Dehradun (Uttarakhand)

WIHG Winter School in Geomathematics Sponsored by Science &amp; Engineering Research Board (SERB) DST, Government of India 16–30 December 2013 at Wadia Institute of Himalayan Geology (An Autonomous Institution of DST, Govt. of India), Dehradun (Uttarakhand)

Study of attenuation mechanism for Garwhal–Kumaun Himalayas from analysis of coda of local earthquakes

The relative contribution of intrinsic ( Q i − 1 ) and scattering ( Q s − 1 ) attenuation to seismic wave attenuation was estimated for the Garwhal–Kumaun Himalayas using Multiple Lapse Time Window Analysis (MLTWA) method under the assumption of isotropic scattering. Local earthquake data recorded by an array operated by Wadia Institute of Himalayan Geology (WIHG), India was used for this purpose. It is observed that scattering attenuation primarily contributes to seismic wave attenuation in this region and its value is much higher compared to that of intrinsic attenuation at around 1 Hz frequency. As frequency increases the relative contribution of scattering attenuation to total attenuation starts decreasing. However, as seismic albedo is higher than 0.5 for all the frequencies considered, it is concluded that the medium here is highly heterogeneous in nature.

Hydrological characteristics of the Dokriani Glacier in the Garhwal Himalayas

Wadia Institute of Himalayan Geology, Dehradun 248 001, India Abstract Observations of discharge, temperature and suspended sediment made at a gauging site established near the snout of the Dokriani glacier in the western Himalayan region are presented. These observations were made during a scientific expedition to this glacier over 21 days (23.8.1992-12.9.1992). Because of harsh weather conditions, obser­ vations could not be made for a longer period. The minimum streamflow in the glacier melt stream was observed at 0700 h whereas the maximum was observed at 1800 h. The ratio of maximum to minimum flow was computed to be 1.81 from the continuous hourly observations. Based on an analysis of the recession of the hydrograph, it was found that the meltwater time lag from the accumulation zone of the glacier was more than seven times higher than that from the ablation zone. No specific relationship was observed between suspended sediment and discharge. The average values of the suspended sediment concentration and load were found to be 350 ppm and 180 t day 1, respectively, for the study period. Weathering processes in different zones of the glacier were also studied to find out the source of the sediment transported by the melt- water into the melt stream. A high correlation coefficient (r = 0.89) was found between the glacier specific runoff and the air temperature at the gauging site. It showed that temperature alone can represent the melting of the glacier and may be considered for the hydrological modelling of glacier melt runoff. Based on observations over three days under clear weather conditions for isolated snow blocks, the average snowmelt factor was computed to be 5.4 mm /(°C. 6 h). Caracteristiques hydrologiques du glacier Dokriani, Garhwal Himalaya

The Uttarkashi earthquake of 20 October 1991: field observations

ABSTRACTThe epicentre of the destructive 20 October 1991 earthquake is in the north‐east of the Uttarkashi region of the Higher Himalaya. The earthquake was felt up to 250–350 km away from Poh and Keylong in the north to Delhi in the south and beyond Chandigarh in the west. Seismologists of the Seismotectonic Group of Wadia Institute of Himalayan Geology studied fissures, surface breaks, and the foreshock and aftershock activity caused by this event. Land fissures show normal dislocations of 0.06–1 m, run E‐W and NE‐SW in the epicentral region and could be followed for 30–40 km.

Contributions to geodynamic research in the Himalaya

Parts of Tethyan and the Higher Himalaya in Ladakh, Kumaun, Garhwal, Arunachal Pradesh and adjoining areas have been investigated by the Wadia Institute of Himalayan Geology. A summary of the geological work carried out in the last five years is presented.

Palaeozoic Biostratigraphy of the Tethys Himalaya in North-Eastern Kumaun

NEW fossil finds in the Kali and Kuti valleys in north-eastern Kumaun Himalaya considerably elucidate the problems of the biostratigraphic subdivision of the Palaeozoic succession and tectonic history of the Tethys Himalaya. Northern Kumaun was explored by Griesbach1–2 in the 1890s and Heim and Gansser3 made this region a classical area for the study of the Tethys Zone of the Himalaya through their monumental work in the 1930s. Although mostly conforming to the general structural picture of the entire Tethys Himalaya, the area showed certain biostratigraphic features that did not agree well with the wide regional stratigraphy and tectonic history as inscribed in the lithological successions in Spiti to the north-west and in West Nepal to the south-east. To study afresh the peculiarities of the Kumaun Tethys Himalaya, an expedition was sponsored and organized by the Wadia Institute of Himalayan Geology in August and September, 1971. Many significant facts have emerged from this short expedition. The new scheme of stratigraphy—with its implication on the tectonic history—accords very well with that established in the Dhaulagiri-Nilgiri region in western Nepal4,5. The highlights of the result of the investigation are as follows.