The Thunder Horse mini-basin consists of several structural features: faulted top basement, autochthonous salt, three allochthonous salt systems (top Albian-99 Ma, top Cretaceous-66 Ma, and Neogene), a raft system with growth fault, and a turtle structure with crestal faults. Remnant salt pillows are present along the 99 Ma horizon, whereas the top Cretaceous allochthonous salt system is identified by a weld.

The evolution of these structural features is detailed in three important intervals: 99, 66, 24, and 14.35 Ma. From 99 to 66 Ma, the top Albian allochthonous salt system deformed into four remnant salt pillows. From 66 to 24 Ma, a northwest trending depotrough developed to the south in association with migration from the top Cretaceous allochthonous salt system. To the north-west, a salt pillow from the top Albian allochthonous salt system continued to rise. From 24 to 14.35 Ma, the depotrough is completely filled with sediment. At 14.35 Ma, the depotrough inverted forming the Thunder Horse turtle structure. Turtle growth continued until about 9 Ma. Finally, major extrusion of the Neogene allochthonous salt sheets occurred between 9.0 and 6.0 Ma, based on the stratal cutoffs against the salt. This salt sheet completely overlies the Thunder Horse North field, and partially overlies the Thunder Horse field.