I was able to spend a solid two hours in the south pit at Arkona this past weekend. The rain went from drizzle to downpour, and as mucky and unpleasant as it might make a sustained outing, the weather this season has been so erratic and rain-soaked that it is nigh impossible to plan collecting trips around (unreliable) forecasts. Still, I made it fairly well in what was mostly a surface collecting operation. The rain brought out the colours of the weathered out fossils very well, making their browns and blacks "pop" for easier spotting. Weathering out of the Arkona clay, I spotted quite a few of these goniatites. On sunny days, at the right angle, the sunlight makes their pyritized surfaces shine and become easily found; in rain, they show up as dark brown against the Arkona shale's light grey. But these are all full specimens. I've arranged these in ascending order of size, and I was quite impressed to find such large ones when a lot of them tend to be hardly larger than the head of a pin. Finding full Eldredgeops rana rollers is not unheard of here, but the place does get picked over so thoroughly that they certainly are tougher to find. This roller (pictured at the bottom) had its pygidium sticking up and my eye was immediately drawn to it. As finding disarticulated pieces are the norm, I was pleasantly surprised when it turned out this one was complete. Pictured above it is a small piece of fish plate. This bumpy piece is a bryozoan. I don't find many of this particular type, and its constellatory arrangement reminded me of when I found that very rare bryozoan at the JD Quarry in June. The amount of coral one has to sift through can be exasperating, but from time to time one encounters a nice piece worthy of putting in the collecting kit. In this case, a multi-cup example where the calyxes are very nicely articulated. A collection of Platyceras spinosum. The one on the far left has still retained some of its stubby spines, while the one in the middle is a juvenile. One little fact about these gastropods is that they were coprophagous (they ate poop!), and so it is common to see them fossilized as being a symbiotic attachment to various creatures, particularly crinoids (although I do have one that affixed itself to a coral). I always manage to pick up little goodies, even if I already have plenty of examples of these already. This assortment is heavily dominated by crinoid ossicles, some with cirra, but if you look closely you will find some tiny nautiloids, brachiopods, and the "button coral" Microcyclus on the upper left hand side. And, finally, below is a short slideshow of some of the above finds under digital microscope at x75 magnification. In all, not a bad haul for two hours collecting in lashing rain! I was able to spend a lovely week in Portugal. In Lisbon, many of the buildings are composed of locally quarried limestone, so you can just look at the walls and see fossils. Sadly, they are mostly oyster fossils with very little detail. I didn't find anything rare or spectacular (but being in Portugal was spectacular enough!). This is a view of Magoita beach. It is rarely visited by tourists, and I am obliged to a Portuguese Fossil Forum member who told me about the place. As one can see, those are massive cliffs, and they date to the Cretaceous period. The deposits are all marine and mostly dominated by oyster shell fossils. I collected at the base of the cliffs where stuff would weather out. We were only there for two hours, so not a lot of time to find all that I wanted. On the way down to Magoita beach, I walked past the fossilized sand dunes - a world heritage site. These have all been hardened by several years of wind and surf. A closeup of the base of the cliffs. From the base of the cliffs again. At the bottom are some weathered out rocks. Some typical oyster shell fossils at the base of the cliff. A nice hash of more oyster shell fossils. A jumble of neat looking turitellid gastropods. Not a fossil, but a pretty cool looking and entirely desiccated little snake. Back in Lisbon, this is from the keep of the Castelos do Sao Jorge. Select pieces from the stuff I brought back home. The two on the right are oyster fossils : Ostrea sp. (Ostrea edulis?). The next one is a deer-heart kind of massive bivalve, possibly Pholadomya sp. Not sure about the clam on the far right, but clams are always a bit trickier to identify because they don't change much over millions of years. This last one is not mine (oh, if it were!). It is Eopelobates sp. on display at the Oceanarium in Lisbon.
|
Kane Faucher
Archives
February 2024
|