Chad Basin depth of . Due to heavy pumping, since the start of the 1980s the water levels in both aquifers has been lowered, and some wells no longer function. There is a third, much lower, aquifer in Bima Sandstones that lies at a depth of . Both the current and historical areas of the basin and the mega-basin contain concentrations of fossils. Fossil-fuels deposits in the area are estimated to exceed a trillion barrels in reserves. The Lake Chad Basin Commission was set up in 1964 by Cameroon, Chad, Niger and Nigeria, the four countries that contain parts of Lake Chad.
Languages of Chad teachers for the deaf train in Nigeria. ("Ethnologue" lists 54 Chadic languages in Chad altogether, many of them small.) Languages of Chad Chad has two official languages, French and Modern Standard Arabic, and over 120 indigenous languages. A vernacular version of Arabic, Chadian Arabic, is the lingua franca. Of the two official languages, French has the most speakers in Chad (though Chadian Arabic has more speakers in Chad than both French and Standard Arabic) . Chad submitted an application to join the Arab League as a member state on 25 March 2014, which is still pending. Chadian Sign Language is