During the Quaternary period, spanning the last 2.6 million years, coastlines have undergone significant transformations driven by glacial-interglacial cycles, sea-level fluctuations, and sediment dynamics. This period saw the development of diverse coastal environments, including expansive clastic systems like beaches and deltas, as well as biogenic systems such as coral reefs. In Southeast Asia, the interplay of these factors is evident in regions like the vast Yangtze and Pearl River deltas in China and the Mekong Delta in Vietnam, where sediment supply from large rivers has historically built extensive deltaic systems. However, recent human activities, such as dam construction upstream, have disrupted sediment flow, commonly leading to downstream issues such as increased coastal erosion and saline inundation. Similarly, in many coastal settings, extensive land reclamation has altered tidal dynamics and sediment deposition patterns, transforming wetlands into urban landscapes. Elsewhere our tropical coral reefs, crucial for coastal protection and biodiversity, have also been impacted by both natural processes and anthropogenic pressures, including climate change, sea level rise and pollution. Understanding these physical and anthropogenic drivers during the Quaternary period is essential for modern coastal management. By integrating geological data with historical and contemporary observations, scientists can develop predictive models to anticipate future changes and devise sustainable strategies to mitigate erosion, manage sediment supply, and protect reef ecosystems, ensuring the resilience of coastal communities in regions throughout Asia.

coastal zone, geology, coastal management, sea level rise, SDGs