Examine the global paleoclimatic and sea-level markers that influenced the geomorphology of the Kerala coastal zone. During Quaternary glacial-interglacial cycles, what primary global process led to the incision of deep bedrock valleys and subsequent sedimentary infilling along the western margin of peninsular India?

💡 Solution & Explanation

During glacial maxima, locked-up ice lowered global sea levels by over 100 meters, causing rivers in Kerala to cut deep valleys into the continental shelf. Subsequent interglacial warming melted ice sheets, raising sea levels and flooding these valleys to form marine transgressions, estuarine environments, and barrier backwater lagoons. Plate subduction does not occur along the passive western margin of India. Solar luminosity changes and volcanic ash do not drive the cyclical coastal valley incision observed. These Quaternary sea-level oscillations shaped the modern coastal topography of Kerala.