A topset is the most proximal compartment of a clinothem rock volume usually consisting of shoreface and delta deposits. topset deposits are deposited nearby wave base and within tidal range. Because of this, sediments in this compartment are deposited in high-energy environments that sequester coarse-grained deposits. topsets can contain porous rocks that form good reservoir rocks. The upper boundary of a topset known as the topset surface, is generally considered to be deposited roughly horizontal or slightly sloping (Klaussen and Helland-Hansen, 2018). It can therefore be used as a paleo-horizontal indicator in seismic or well log data, allowing researchers to reconstruct depositional geometries and orientations of clinothem strata.