Located near the town of the same name, it documents well-preserved deepwater marine fossils dating to the late Santonian stage of the Cretaceous.

However, unlike the Sannine Formation sites, which were deposited in relatively shallow waters near the shore on the inner continental shelf, Sahel Alma was deposited in a deepwater habitat off the continental slope, at depths estimated to be greater than 150 metres (490 ft), likely at the transition between the sublittoral and bathyal zones in dysphotic or aphotic conditions.

[1][3] As with the sites of the Sannine Formation, the fossils of Sahel Alma are very well-preserved, and include the soft body parts of cartilaginous fish and cephalopods.

It has been known of since the Seventh Crusade in the 13th century, when bricks quarried out of it were used to build the eponymous Maronite monastery at Sahel Alma.

British adventurer Lady Hester Stanhope settled near Sahel Alma in the early 19th century, and helped to collect and circulate fossils from the site and Haqel.