Abundant evidence from the Northern Gulf of Mexico Basin suggests that late Early Cretaceous to Recent sea-floor spreading is the principal factor in the formation of the structural components of this basin. This would classify the Gulf of Mexico Basin as an active tectonic basin as opposed to the more accepted passive basin status. The following two-part paper presents a model for this lithospheric plate adjustment together with the geological evidence to support this movement. Part 1 discusses the rift model and supporting evidence. Some of this evidence is: a proposed triple-junction rift zone radiating from a large dome centered in the DeSoto Canyon area; the division of the Gulf of Mexico Basin Jurassic salt province into three salt basins (the Interior, Exterior, and Challenger Basins); the linearity and structurally-positive attitude of the Cretaceous Shelf Edge; an excessive Exterior Basin salt mass that thickens towards the Sigsbee escarpment; large areas of non-diapiric salt found within the Exterior Basin; an extensional fault zone found underlying the Abyssal Plain; and the absence of a Late Mesozoic section from the Exterior Basin, a section that would be needed to cover the salt until it was overlain by younger Tertiary sediments. Part 2 discusses further evidence for an active Gulf of Mexico Basin, and includes the following observations. The recorded positive gravity response in the Exterior Basin is in conflict with chick Louann salt found there. Possible lithospheric plate boundaries are outlined by linear magnetic signatures, recorded earthquake epicenters and centers of active and dormant volcanism. Magnetic, deep refraction and reflection data record a ridge-and-valley basement complex running parallel to these lithospheric plate boundaries. Refraction and reflection data allows the Challenger salt layer to extend northwards under the Abussal Plain, and to connect to the Exterior Basin Louann salt layer Eastern Cretaceous Shelf Edge paleostructural restoration shows doming along this linear structure from the early Late Cretaceous through the Early Tertiary, which corresponds to Albian-early Cenomanian through Early Tertiary linear doming in the offshore area of eastern Mexico. Eastern Mexico＇s Tuxlas volcanic field appears to be part of the Trans-Mexico neovolcanic belt that has been relocated along a transform fault. Other lines of evidence are also considered.