Endorsing Trusheim’s classic model of salt-diapir growth by the interpretation and restoration of seismic lines in the southern region of the Great-Tunb Island, Persian Gulf

This paper investigates the geometry and evolution of the Oligocene and lower Miocene Fars salt diapirs and adjacent minibasins in the southeast Persian Gulf. Utilizing 2D offshore seismic lines, integrated with well data, we conducted detailed interpretations to construct NE-trending geological cross-sections south of the Great-Tunb Island. Subsequent stepwise restoration, guided by thickness patterns of syn-kinematic sediments, local unconformities, growth strata, and halokinetic sequences, unveiled the growth history of salt massifs, turtle anticlines, and salt horns featuring normal fault systems at their crests. Our findings reveal a synchronous evolution of Fars salt diapirs and nearby minibasins, aligning significantly with the classic Trusheim concept (1960). The identified stages encompass; 1) The pre-kinematic stage, coinciding with the deposition of the Gachsaran Formation in the Lower and Middle Miocene; 2) the Growth of salt pillows, concurrent with the basal deposition of the Guri Member at the Middle and Late Miocene boundary; 3) Passive and rapid diapir growth, synchronous with the Guri Member deposition in the Late Miocene; and 4) The post-diapirism stage and basins associated with salt incompressibility, corresponding to the deposition of the Upper Mishan and Aghajari formations during the Late Miocene and Pliocene times.Keywords: Salt diapirism, Marine seismic data, Kinematic evolution, Minibasin, Fars Salt, Hormuz Salt