Dead Sea hypothesis is that the Dead Sea lies in a true rift zone, an extension of the Red Sea Rift, or even of the Great Rift Valley of eastern Africa. A more recent hypothesis is that the Dead Sea basin is a consequence of a "step-over" discontinuity along the Dead Sea Transform, creating an extension of the crust with consequent subsidence. Around 3.7 million years ago, what is now the valley of the Jordan River, Dead Sea, and the northern Wadi Arabah was repeatedly inundated by waters from the Mediterranean Sea. The waters formed in a narrow, crooked bay that is
Poxte River River, which is a tributary of the Machaquila River. The Machaquila River feeds into the Pasión River, which flows into the Usumacinta River and into the Gulf of Mexico. The upper reaches of the Poxte River shares its drainage with the Mopan River, which flows eastwards into the Caribbean Sea. The Poxte River Basin itself measures long and is wide. The river valley drainage is broken and confused, and the land has been largely cleared of forest in order to graze cattle. The Poxte valley includes modern settlements of Las Nuevas Delicias, La Lucha, Santo Domingo and Boca del Monte.