The Furnace Creek Fault system, located in what is now the northern part of Death Valley, started to move about 14 Ma and the Southern Death Valley Fault system likely began to move by 12 million years ago. Both fault systems move with a right-lateral, or dextral, offset along strike-slip faults. With such faults, the opposite side of the fault appears to be moving right when facing the fault from either side. Both fault systems run parallel to and at the base of the ranges. Very often the same faults move laterally and vertically, simultaneously making them strike-slip "and" normal (i.e. oblique-slip). These two systems are also offset from each other; the area between the offset is thus put under enormous oblique tension, which intensifies subsidence there; Furnace Creek Basin opened in this area and the rest of Death Valley followed in stages. One of the last stages was the formation of Badwater Basin, which occurred by about 4 Ma. Data from gravimeters show that Death Valley's bedrock floor tilts down toward the east and is deepest under Badwater Basin; there is of fill under Badwater. By about 2 Ma Death Valley, Panamint Valley and their associated ranges were formed.