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The application of high resolution seismic data using boomer sound source has revealed a wide distribution of large-scale bedforms (sandwaves) on the Southeast Vietnam continental shelf. Bedforms that are a few meters high in wave height and hundreds of meters long in wavelength are primarily developed in the inner shelf (20-40 m) and considered to be formed under the presentday marine hydrodynamic conditions. Those bedforms developed in the deeper water (120 m) of the northernmost part of the continent can be interpreted as the relict morphological features formed during the latest sea-level lowstand of the late Pleistocene period. Two sediment transport paths have been identified on the basis of the bedform's leeward orientation: northeast-southwest (alongshore) and north-south (cross-shore). A quantitative bottom current map is constructed from sandwave dimensions, surface sediments and measurement data. The strongest current velocities that gradually decrease toward the southwest are indicated by large sandwaves in the north (field B). Water depth, surficial sediment composition and bottom current are three factors that control the development of bedforms.

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Sediment supply, subsidence, and eustasy are the main factors controlling the geometry of strata that form in a basin that is being filled. The strata formed, called sequences, are interpreted in order to correlate and predict stratigraphy on a regional to global scale and on a range of time scales. Although the principle of sequence stratigraphy is simple, the numerous degrees of freedom and the many possibilities of interpretation make it difficult to understand for many students and scientists.

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