https://libjncir.jncasr.ac.in/xmlui/handle/10572/1854 GDU 2026-04-04T05:31:47Z https://libjncir.jncasr.ac.in/xmlui/handle/10572/2595 Damming rivers in the tectonically resurgent Uttarakhand Himalaya Valdiya, K. S. In the fault-ridden, seismically and tectonically active belts recurrently ravaged by excessive rains and. resultant landslides in Uttarakhand a very large number of big and small dams are being constructed and planned. Quite many of these projects suffered crippling damages during the 2013 disaster as mountain slopes slid down and floodwater severely eroded stream banks and dumped huge volumes of sediments on critical facilities. If the idea is to have environment-friendly power projects, then the planners and dam builders must not ignore the geological reality of the geodynamically sensitive region. Better sites for dams can be explored far upstream of the Main Central Thrust Zone. Open Access 2014-01-01T00:00:00Z https://libjncir.jncasr.ac.in/xmlui/handle/10572/2585 Sheltered coastal environments as archives of paleo-tsunami deposits: Observations from the 2004 Indian Ocean tsunami Andrade, Vanessa; Rajendran, Kusala; Rajendran, C. P. The 2004 earthquake left several traces of coseismic land deformation and tsunami deposits, both on the islands along the plate boundary and distant shores of the Indian Ocean rim countries. Researchers are now exploring these sites to develop a chronology of past events. Where the coastal regions are also inundated by storm surges, there is an additional challenge to discriminate between the deposits formed by these two processes. Paleo-tsunami research relies largely on finding deposits where preservation potential is high and storm surge origin can be excluded. During the past decade of our work along the Andaman and Nicobar Islands and the east coast of India, we have observed that the 2004 tsunami deposits are best preserved in lagoons, inland streams and also on elevated terraces. Chronological evidence for older events obtained from such sites is better correlated with those from Thailand, Sri Lanka and Indonesia, reiterating their usefulness in tsunami geology studies. (C) 2014 Elsevier Ltd. All rights reserved. Restricted Access 2014-01-01T00:00:00Z https://libjncir.jncasr.ac.in/xmlui/handle/10572/2586 Slow Slip Acceleration beneath Andaman Islands Triggered by the 11 April 2012 Indian Ocean Earthquakes Paul, J.; Rajendran, K.; Rajendran, C. P. The M-w 8.6 and 8.2 strike-slip earthquakes that struck the northeast Indian Ocean on 11 April 2012 resulted in coseismic deformation both at near and distant sites. The slip distribution, deduced using seismic-wave analysis for the orthogonal faults that ruptured during these earthquakes, is sufficient to predict the coseismic displacements at the Global Positioning System (GPS) sites, such as NTUS, PALK, and CUSV, but fall short at four continuous sites in the Andaman Islands region. Slip modeling, for times prior to the events, suggests that the lower portion of the thrust fault beneath the Andaman Islands has been slipping at least at the rate of 40 cm/yr, in response to the 2004 Sumatra-Andaman coseismic stress change. Modeling of GPS displacements suggests that the en echelon and orthogonal fault ruptures of the 2012 intraplate oceanic earthquakes could have possibly accelerated the ongoing slow slip, along the lower portion of the thrust fault beneath the islands with a month-long slip of 4-10 cm. The misfit to the coseismic GPS displacements along the Andaman Islands could be improved with a better source model, assuming that no local process contributed to this anomaly. Restricted Access 2014-01-01T00:00:00Z https://libjncir.jncasr.ac.in/xmlui/handle/10572/2292 Geological marvels, hallowed shrines and unification of people of India Valdiya, K. S. Spectacular landforms and extraordinary geological features sculptured by uncommon earth processes occur in different parts of the Indian subcontinent. Presumably, unable to unravel the mysteries of their origin, and realizing that singularly odd features located in picturesque places attract believers and non-believers alike, the leading lights of the society of ancient India invested them with the aura of divinity and established shrines of the commonly venerated deity. Influencing convincingly people belonging to diverse racial-ethnic groups inhabiting different parts of the country, speaking languages belonging to disparate groups, indulging in different socio-cultural practices and eating and dressing differently, to go on regular visits to these hallowed sites or seats of deity, the visionary sages and seers of the ancient India endeavoured successfully to promote interactions of visitors to these geological marvels located in different parts of the country and bring about cross-fertilization of thoughts and cultural elements, and thus the unification of the largest section of the population. Open Access 2016-01-01T00:00:00Z