Understanding the Andaman Seafloor: A Geospatial Journey into Tectonics and Seamounts

It was during my Master’s dissertation that I got a chance to explore one of the most tectonically intriguing regions of our planet, namely, the Sunda-Andaman subduction zone. I was first attracted to this particular region due to its immense geo-dynamic importance. Highly tectonic regions are often said to hold the key to deciphering the various geological processes that are at play in our ever-evolving planet.

By exploring these regions, we do not just get to understand our geological past, but also get a fair idea of the processes that are still at play in these regions, thus evolving our planet as we know it today. However, my fascination with this particular region was further enhanced by my stint at the National Institute of Oceanography in Goa. A new curiosity was kindled within me, namely, what exactly lies beneath the ocean’s surface, and how can we decipher these geological secrets that are hidden beneath the ocean’s surface.

Why Tectonics and Geodynamics Fascinate Me

Tectonics and geodynamics are also closely inter-related. The link between tectonics and geodynamics allows us to understand the evolution of the landscape and the ocean basins through time.

For me, this link between tectonics and geodynamics is interesting because it allows us to catch a glimpse of the interaction between the Earth’s systems.

The Role of Seamounts in Understanding Subduction Zones

The main focus of my dissertation was based on the analysis of the structural and morphological characteristics of seamounts in the Andaman forearc basin. Seamounts can be defined as underwater mountain formations that emerge from the ocean bed. These formations are attributed to various volcanic activities that are a result of tectonic activities.

Seamounts that are located in tectonically active regions, including the Andaman-Nicobar island chain, have been instrumental in providing valuable information about tectonic activities that have taken place in these regions. By analysing these formations, it is possible to understand the relationship that exists between volcanic activities and tectonic activities in these regions.

Sunda-Andaman subduction zone can be defined as part of a broader tectonic setting that includes the Sunda Trench and the Indonesian volcanic arc. This tectonic setting is important globally due to the activities that have been taking place in this region over time, including massive earthquakes and resulting tsunamis. As such, it is important to understand the geological setting of this area for reasons that are beyond academic interest.

After identifying these seamounts, I was also able to characterise them depending on their major morphological characteristics, which included their height, width, and volume. This was important in helping me quantify their size and structure, as well as their formation patterns.

In addition, it was also important for me to characterise these seamounts depending on their different morphological types, which included:

•Conical seamounts

•Guyots

•Calderas

These different morphological types are likely to be associated with different patterns of formation.

Figure 3: Seamount classification of North Region of Andaman and Nicobar Islands.

A Personal Reflection

Prior to this dissertation, I never thought that I would be this fascinated by the concept of research. However, the five months I spent on this dissertation have completely changed my perception.

I have come to realise that the essence of research lies in the curiosity of the individual. The fact that I have spent my time studying the seafloor structures, geological patterns, and the connection to tectonic plates has helped me realise my career aspirations.

Although I am currently employed, I have set my sights on a career shift towards the world of research. I have not set my sights on any of the ‘Eureka’ moments; however, I do believe that I have the ability to contribute to the world of science in a meaningful way.

One of the most interesting finds was the relationship between seamount morphology and tectonic evolution in the forearc basin. The conical seamounts in some regions indicated a younger and more active tectonic environment. Conversely, the greater number of guyots and caldera seamounts indicated the presence of older and less active volcanic features.

Women in Geospatial and Marine Geoscience

Marine geoscience and tectonics are vast and complex areas, layered and interconnected in many ways.

I encourage more women to enter these areas as geospatial science gives us the ability to visualise and interpret the Earth in a new and innovative way, using analytical thinking and creativity.

For me, this whole study of the Andaman seafloor wasn’t just about studying the seafloor, but also a reminder of the interconnectedness of our planet. And if we ever hope to better understand the dynamic planet, we call home, these interconnected areas are crucial.

About the Author

Susan Carol Thomas is a GIS engineer and geospatial analyst with experience in applied geology and spatial data science.