Recently returned from two weeks in Jamaica, and particularly in Ocho Rios (St Ann's Parish). The primary purpose of the trip was undoubtedly much-needed R&R after a hectic semester, so swimming in the ocean, drinks by the pool, and the usual laying about dominated our time there. Still, the lure of fossils is always strong. About 75% of Jamaica's rocks are limestones dating back to the late Mesozoic and Cenozoic. The formation of Jamaica as it stands above water today was the result of successive volcanism. Today, it is surrounded by a diverse coral reef marine ecosystem, and has some mountainous peaks (primarily Blue Mountain, the base of which we were staying). The limestones themselves are almost entirely dominated by coral fossils, with some gastropods in the mix. The limestone is quarried from many areas and used extensively for local building needs. When these appear as large blocks sitting around, closer inspection reveals that much of the rock is fossil coral. Pictured here are some examples, including a scleractinian coral colony. Sadly, despite some efforts, I could not arrange to go off property to inspect some larger, natural exposures. Some exposed beds at larger quarrying sites or roadcuts rise to over 200 metres. Pictured here are just a few of the shorter roadcuts, snapped from a moving shuttle bus. These are fairly typical of the island's limestone beds, although not pictured here would be the strata that is more of an orange-brown. With such an abundant supply of limestone, it is used in many ways. These saw-cut patio tiles around one of the pools contain cross-sections of high-spired gastropods of some considerable size. More poolside tiles with fossils. I'm sure there would be some issues if I decided to extract this from the pool side, but it would be neat to be able to prep out the other side in 3D. There are little spoil piles in out of the way places everywhere. Some of these are discards from being shaped into wall pieces, or stuff to be used as filler elsewhere. I went poking around on the fringes of the property, behind all the resort action. All coral fossils. It's not easy to go scrambling over piles in your flip flops. This scleractinian coral fossil was my keeper from these piles. I later cleaned up all the dirt pictured on this one, and it looks nice. With luggage weight requirements, I really can't be hauling back anything more than fragments! Case in point would be this chunk (closeup detail on the right). This stuff is very dense, and without a hammer it becomes nearly impossible to crack out a piece without turning it into dust while bashing against other rocks. Some in situ pics along the beach where the cliff was close to shore. This stuff is fairly resistant to the pounding of the waves. Not all the patio material is derived from fossiliferous rock. Pictured here would be "fakes." The left side depict tiles that are clay and based on a mould. The one on the right is simply poured concrete with a sectioned modern shell. Using large leaves as imprints on the wet concrete give it a neat aesthetic.
Ok, so no big fossil haul, but still interesting to bump into fossils while on vacation. When I came back home, there were a number of packages waiting for me, with others waiting for pick up at the post office., They are all trilobites, with a few for me to prepare. Stay tuned... Comments are closed.
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Kane Faucher
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February 2024
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