Halokinetic sequences are unconformity-bound packages of thinned and folded strata adjacent to passive diapirs. Hook halokinetic sequences have narrow zones of deformation (50–200 m), >70° angular discordance, common mass-wasting deposits and abrupt facies changes. Wedge halokinetic sequences have broad zones of folding (300–1000 m), low-angle truncation and gradual facies changes. Halokinetic sequences have thicknesses and timescales equivalent to parasequence sets and stack into composite halokinetic sequences (CHS) scale-equivalent to third-order depositional cycles. Hook sequences stack into tabular CHS with sub-parallel boundaries, thin roofs and local deformation. Wedge sequences stack into tapered CHS with folded, convergent boundaries, thicker roofs and broad zones of deformation. The style is determined by the ratio of sediment-accumulation rate to diapir-rise rate: low ratios lead to tabular CHS and high ratios result in tapered CHS. Diapir-rise rate is controlled by the net differential load on deep salt and by shortening or extension. Similar styles of CHS are found in different depositional environments but the depositional response varies. CHS boundaries (unconformities) develop after prolonged periods of slow sediment accumulation and so typically fall within transgressive systems tracts in shelf settings and within highstand systems tracts in deepwater settings. Sub-aerial settings may lead to erosional unroofing of diapirs and consequent upward narrowing of halokinetic deformation zones.

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Passive-margin salt basins are classified as prerift, syn-stretching, syn-thinning, and syn-exhumation. Prerift salt, such as the Triassic Keuper in the Western Pyrenees, undergoes thick-skinned extension, first decoupled and then coupled, along with its substrate and cover. The base salt develops significant relief, is attenuated on the largest faults, and ends up distributed across the entire margin. Syn-stretching salt, such as along the Iberian and Newfoundland margins, is deposited during early rifting and is thus concentrated in proximal areas with variable thickness and extent, with decoupled and coupled thick-skinned deformation dominant. Syn-thinning salt, such as in the northern Red Sea, is also deposited during extension, with the base salt unconformably above proximal stretching faults but offset by distal thinning faults. Both thick-skinned and gravity-driven thinskinned deformation occur, with the latter strongly influenced by the ramp-flat geometry of the base salt. Syn-exhumation salt, such as in the Gulf of Mexico and South Atlantic salt basins, is deposited as part of the sag basin with broad distribution and a generally unfaulted base. Conjugate syn-exhumation salt basins are originally contiguous, form partly over exhumed mantle on magma-poor margin segments, and are commonly flanked by magma-rich segments with volcanic highs (seawarddipping reflectors) that isolate the salt basin from marine water. Salt tectonics is characterized by gravitational failure of the salt and overburden, with proximal extension and distal contraction, and the development of allochthonous salt that includes frontal nappes that advance over newly formed oceanic crust.