Kem Kem Group
The Kem Kem Group is a geological group in the Kem Kem region of eastern Morocco, whose strata date back to the Cenomanian stage of the Late Cretaceous.
Dinosaur remains are among the fossils that have been recovered from the group. Recent fossil evidence in the form of isolated large abelisaurid bones and comparisons with other similarly aged deposits elsewhere in Africa indicates that the fauna of the Kem Kem Group may have been mixed together due to the harsh and changing geology of the region, when in reality they would likely have preferred separate habitats and likely would have been separated by millions of years.
Stratigraphy and paleoenvironment
Although preserving a freshwater habitat located near a river delta, the Kem Kem deposits were quickly submerged by the sea during the Cenomanian-Turonian boundary event, and are thus overlaid by the marine deposits of the younger latest Cenomanian and early-mid Turonian-aged Akrabou Formation, which was formerly also considered a member of the Kem Kem Group, but has been differentiated from it in more recent studies due to their differing paleoenvironments.'Its strata are subdivided into two geological formations, with the lower Ifezouane Formation and the upper Aoufous Formation used for the strata on the eastern side of the Atlas Mountains, with the Gara Sbaa Formation and Douira Formation used in the southern Tafilalt region. It is exposed on an escarpment along the Algeria–Morocco border. According to Ibrahim, the Lower Kem Kem consists of the Ifezouane & Gara Sbaa Formations, while the Upper Kem Kem is consisted of The Douira & Aufous Formations. '
The unit unconformably overlies Paleozoic marine units of Cambrian, Silurian and Devonian ages and is itself capped by limestone platform rock of Cenomanian-Turonian age. It primarily consists of freshwater and estuarine deltaic deposits. The lower Gara Sbaa Formation primarily consists of fine and medium grained sandstone, while the Douira Formation consists of fining-upward, coarse-to-fine grained sandstones intercalated with siltstones, variegated mudstones, and occasional thin gypsiferous evaporites.
The Kem Kem is interpreted as being deposited in a tropical semi-arid climate, with brief monsoon rains. It is believed to Span the Lower to Middle Cenomanian, a span of roughly 100-95 mya. ''''''