Sharks of the Moroccan phosphates

Dr Charlie Underwood (UK) Shark teeth are amongst the most iconic and sought after of fossils. However, for most of us, collecting them can be a difficult or even unpleasant task. I am sure that most collectors in northern Europe are familiar with picking their way over slipped cliffs of clay, in the teeth of a freezing winter gale, to collect the few treasures that erosion leaves on the beach. Alternatively, the more dedicated are used to carrying hundreds of kilos of clay home and painstakingly passing it through a sieve before even knowing if there are any fossils there. But it is not all like this. There are a number of places in the world where the vagaries of sedimentology have allowed bone-beds (or phosphorites) to develop, within which vertebrate fossils, and shark teeth in particular, are hundreds of times more abundant than in a normal marine sediment. By far the most extensive of these deposits are in Morocco. Below the dusty scrub and parched farmland of northern Morocco lie the largest reserves of mineral phosphate known. Vast complexes of open-cast mines, one stretching for nearly 30km, have been cut into these deposits, with a network of conveyor belts transporting the phosphate sand and rock to the processing factories turning the rock into fertilizer. These great phosphate deposits were laid down in a sea saturated with nutrients and teeming with life. As a result, the phosphates are crammed with the fossilised phosphatic bones and teeth of fish, sharks and … Read More