First-order tectonic control on the geomorphological evolution of the coastal zone of Timor-Leste: integration of Quaternary inheritance, relative sea level, and coastal processes
DOI:
https://doi.org/10.9771/geocad.v21i0.72458Keywords:
Timor-LesteAbstract
Coastal zones in tectonically active settings exhibit high geomorphological complexity arising from the interaction between crustal deformation, relative sea-level variations, and coastal processes. In such contexts, models developed for passive margins are often insufficient to explain landform organization and the preservation of the Quaternary record. This study examines the geomorphological organization of the coastal zone of Timor-Leste, located within the Banda Arc–Australian continent collision zone, based on systematic geomorphological mapping at a scale of 1:12,500 using integrated optical imagery, radar data, and digital elevation models. The results reveal pronounced spatial heterogeneity, including segmented coastal plains, discontinuous marine terraces, and marked altimetric variability. These patterns indicate a first-order tectonic control, whereby differential uplift modulates relative sea level and governs selective preservation of Quaternary surfaces, while coastal hydrodynamics acts as a subordinate redistributive process. The proposed evolutionary model highlights the central role of active tectonics in shaping coastal geomorphology and positions Timor-Leste as a key case study for tectonically active coasts.
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