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This study attempts to identify fluvial architecture and document channel and channel belt dimensions of central Pattani Basin within Upper Miocene to Holocene interval by using seismic geomorphology and well log data. Many seismic attributes such as RMS, sweetness, semblance and spectral decomposition were computed to map channel morphology. Forty (40) horizon/time slices were analyzed to understand evolution of channel systems within the zone of interest. We measured key channel parameters to quantify channel morphology. Amplitude spectra of spectral decomposition and sweetness are found to be the most useful attributes. Image quality can be enhanced if semblance is combined with other attributes by adjusting the opacity level. Different fluvial styles are identified in different parts of the study area including high sinuosity system with broad meander belt, sand filled channel, low sinuosity distributary system and broad incised fluvial system with tributary valleys. The study interval can be divided into five periods based on channel morphology. Period 1 (900–700 ms) has moderate to high sinuosity channels in lower part, while in the upper part; it has low sinuosity systems. High sinuosity channel features representing well-developed meander belt dominated in Period 2 (700–600 ms). Period 3 (600–450 ms) comprised of wide and low sinuosity channels associated with coal deposition. Period 4 (450–250 ms) is characterized by possible marine deposition during high sea level with occasional fluvial intervene. Period 5 (250–100 ms) is represented by highly sinuous broad fluvial systems deposited within incised valley. Such variation in the fluvial styles would serve as a warning as to a rather simplistic assumptions on the channel scale and styles during reservoir modeling. Keywords: Fluvial architecture, Seismic geomorphology, Semblance, Spectral decomposition, Stratal slicing, Sinuosity, Incised valley