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Extreme wave events of 1000 and 1500 years (radiocarbon ages) have been recently reported in Mahabalipuram region, southeast coast of India. Subsequently, we carried out extensive sedimentological analysis in regions covering a total lateral coverage of 12 km with a new archeological site as the central portion of the study area. Twelve trenches in shore normal profiles exhibit landward thinning sequences as well as upward fining sequences confirming with the global signatures of extreme wave events. The sediment size ranges from fine-to-medium and moderately well sorted-to-well sorted, and exhibit positive skewness with platykurtic-to-leptokurtic nature. We now propose the abrupt winnowing or back and forth motion including unidirectional transport of these deposited sediments, which results in positive skewness. Textural analyses derived from scanning electron microscope studies (SEM) demonstrate the alteration produced, in the ilmenite mineral with vivid presence of pits and crescents with deformation observed on the surface due to extreme wave activities. This is further confirmed with the predominance of high-density mineral such as magnetite (5.2) and other heavy minerals in these deposits inferred the high-intensity of the reworking process of the beach shelf sediments.

The 2004 Indian Ocean tsunami caused massive devastation and left a lasting impact along many of the major coastal regions in South Asia, including the coast of Tamil Nadu, a state in the southeastern tip of India. Following the event, sand deposits draped the low‐lying areas and buried the muddy sediments of the coastal plain [Babu et al., 2007; Srinivasalu et al., 2007]. In addition, erosional features related to the tsunami, such as channels and scarps, have been observed along many parts of the coast (Figure 1a). This tsunami, along with a recorded history of intense monsoons, has highlighted the need for focused research on the role of extreme events in shaping the geological character of India's coastal plains.

Long-term structural monitoring has become an important requisite to ensure structural and operational safety for critical civil infrastructures. Long-term structural monitoring by acquiring data continuously or at small intervals may be difficult to achieve by employing conventional on-site monitoring methods. In order to overcome these difficulties remote structural monitoring (RSM), an advanced structural monitoring technique, can be used to acquire continuous data from the remotely instrumented structure. RSM methodology requires an interdisciplinary approach integrating areas such as structural engineering, sensor technology, communication technology, statistical mechanics, information technology for online data transmission (over larger distances) and damage detection/ health assessment of the structure. RSM has many advantages like, continuous monitoring, early alarm of any incipient damage, and data acquisition even in adverse climatic/environmental conditions. This article describes the development of an RSM scheme, developed at SERC, Chennai. The article outlines the laboratory and field investigations carried out to validate the developed scheme. Brief information about the observations and modifications made during these trials are also presented. A part of the work carried out for synthesizing online data using Auto Regressive Moving Average model is also presented.