The campos basin was formed as a result of the breakup of gondwana in the early cretaceous.The basin has several main structural elements (figure 3): (1) northeast- and northwest-trending horsts and grabens mapped at the neocomian basalt reflector; (2) pre-aptian structures related to the campos fault; and (3) a salt dome province, which is an extension of the sao paulo plateau in ultra-deep water.This was followed by subsequent infilling of the rift basin with as much as 9000 m of early cretaceous-holocene sediments, as shown in the stratigraphic chart of figure 2.The sedimentary section of the campos basin can be subdivided into three megasequences.(Figure 2)