C.P. Rajendran, Ph.D.

Centre for Earth Sciences (CEaS)   

Indian Institute of Science

Bangalore 560012, India                                 

 

Phone: 91-80-2293-3402(O)

            91-80-2360-0126(R)

 

e-mail: cprajendran@ceas.iisc.ernet.in

alt. e-mail: cp.rajendran@yahoo.com

Education

Post-doctoral fellow 1989-1993; University of South Carolina, USA

Ph.D. 1988; Cochin University of Science and Technology, India

M.Sc. 1978; Cochin University of Science and Technology, India.

B.Sc. 1976; University College, University of Kerala, India.

Professional Experience

 2008-present: Indian Institute of Science, Bangalore (Ramanujan Fellow)

1979-1989;1993-2008: Ctr. for Earth Science. Studies, Trivandrum (scientist)                                                                                  

 Areas of Research

Earth processes: earthquake and tsunami hazards, subduction tectonics and crustal deformation, Holocene geology, climate and landscape evolution.

 Charles Lyell in his “Principles of Geology” was perhaps the first to appreciate the scientific value of landscape changes, created by earthquakes. A classical case, among others, to which he made reference, was the 1819 Rann of Kachchh earthquake that produced dramatic land level changes. This earthquake produced a linear elevated tract of land called “Allah Bund” in the low-lying Rann in the northwest India, which even changed the course of a tributary of Indus River. A pioneering geologist from the colonial India, Thomas Oldham has also contributed much to the early understanding of the surface expressions of the great earthquakes (e.g. the 1897 Shillong earthquake of the northeast India), and equally importantly how such surface effects could be used to understand the earthquake mechanisms. This line of research, after a long unexplained gap, has picked up now in various parts of the world, as one of the important tools in seismic hazard evaluations. “Paleoseismology”, which means “study of past earthquakes”, has now gained currency among the geoscientists, as major tool in seismic hazard studies.

 

I am involved in pursuing this line of research activity focusing on the geological aspects of the earthquakes. Through each earthquake, the nature briefly reveals itself. I observe the morphological changes, which include surface displacement during an earthquake and also the secondary impacts like soil liquefaction and surface deformations to decipher the individual characteristics of the causative earthquake. The source areas of large earthquakes tend to preserve these earthquake expressions in the landscape and in the shallow geological records. From the study of such preserved records and constraining the ages of the features, I deduce the recurrence of the earthquakes and associated hazards, and in some cases also the tsunamis that emanate from sea-quakes. In short, I like to understand an earthquake from a geological perspective, a “quantum” in the geological continuum that shapes the earth’s surface.

 

I like to address the issues like where the earthquakes most likely to occur; what controls their distribution in space and time; and how large are these expected earthquakes? Through the study of earthquakes I try to understand the ongoing tectonic movements (active tectonics). I take recourse to the inputs from GPS (geodesy) and seismology to supplement my geological observations. With the combined use of various disciplines I try to address the problems of earthquake generation and recurrence. Not all faults produce earthquakes; I like to understand which are the potential faults that can generate earthquakes.

 

The Indian subcontinent provides some of the unique and spectacular examples of earthquake source areas. The variety of source zones in India allows me to work in the continental interiors, and also in areas where the plates interact, such as the Himalayan belt and the Andaman-Nicobar Arc (which in 2004 generated an unprecedented transoceanic tsunami), and occasionally I stray to areas elsewhere in the world. Recently, I was working on the Iranian coast of Makran to understand the tsunami and earthquake recurrence in the region. 

 

Each area presents an array of earthquake behavior in terms of fault activity, landscape changes and active tectonics, which essentially say that these processes are complex and non-uniform, but I find there is an underlying unity of processes within this diversity. Ultimately I am interested to decipher the common characteristics and behaviors that define various seismic source zones, most importantly a geologically meaningful recurrence model for individual seismotectonic provinces in India, and how they compare with earthquakes globally.

                                                                                                           

 Areas of Research

Earth processes: earthquake and tsunami hazards, subduction tectonics and crustal deformation, Holocene geology, climate and landscape evolution.