Hakel’s specimens are preserved in lagerstatten, formed by a fine-grained (micritic), finely laminated plattentalk, the Hakel fossil layers have been defined as Cenomanian, 98 Million years. The limestone is well stratified, the color is also impressively variable from a pallid yellow to a brown-beige, to grey to near black. The limestone of this restricted area probably represents one of the richest deposits of fossil fish in the world. Mass mortality layers are relatively frequent; multiple fish slabs are regularly found in this locality. Fish are the most common fossils found in this area, but crustaceans, plants and echinoderms are also present.

The first homeland of these fossils was the Thethys sea which covered a large part of the Mediterranean countries and the Lebanese territory, 220 million years ago. The fossil animals lived by the coastline 98 million years ago, precisely in the Cenomanian age. The excellent state of preservation of these fossils, indicates a sudden and simultaneous death which can be explained as below. After heavy rains, microscopic animals and plants (plankton) developed on the water surface, sometimes changing the color of the sea which turned thus reddish or greenish. Such a phenomenon is currently witnessed on some coasts and is known by the name of “waterbloom” Not only does this plankton use all the oxygen in the seawater, but it also releases substances that poison sea animals and cause their sudden death. Fish and crustaceans thus die and sink to the bottom of the sea in large numbers. The fossilization conditions of that period were excellent: an oxygen-deprived sea bottom and a fast deposit of sediments on the bodies which do not have the time to decompose and are thus entirely kept. Following a movement of continental plaques (tectonic movement) accompanied by a drop of sea level, Mount Lebanon appeared, erosion later revealed the layers where the fish originally were.