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This past Sunday, I had about 2 hours to spare, and wanted to look for fossils. I obviously couldn’t go far, so I decided to see whether I might have any luck fossil hunting along the Iowa River right in Iowa City. The exposure there is from the Coralville Member of the Cedar Valley Formation, which is mostly Devonian limestone and Dolomite. The faunal diversity in this strata is not great - some solitary and colonial corals, a smattering of brachiopods and bryozoans, and a few small crinoidal columnals. I had time to check out two locations very near downtown Iowa City, and both within two miles of my house. The banks leading to the river in this area are relatively short (~10-15 feet), but can be steep and/or blocked by dense vegetation. The first location allowed access to the river via a small boat launching ramp. The river at that point is not scenic and the brief stretches of shoreline contain a surprising amount of large discarded slabs of concrete. This must have been near somebody’s favorite fishing spot, as I saw a chair perched neatly on the stones of the shore. I poked around for a bit and found quick collection of some species of the colonial coral Hexagonaria. I assembled the finds for this photo. They are not that well-preserved. I did find it interesting that some pieces are brownish and contained open corallites without intact septa. These were all thin sheets about 10 mm thick. Other pieces were thicker and larger, grayish stones whose corallites were filled in. I didn’t find much else there other than a small patch of some species of the Bryozoan fenestella a beat-up brachiopod and an even more beat-up solitary rugose coral. With only 45 minutes left, I went about ¾ of a mile north, where there’s a rough, worn-out path to the river; a path likely made by people going down to fish. Here I had more luck, finding a place I’ll return to later when I have more time. I almost immediately found two very large rocks with plenty of brachiopods in them. Unless you zoomed in very close to where my fingers touch the rock in the second picture, you are sure to have missed my favorite find. Here it is zoomed in more closely. Both valves of a fairly large Platyrachella iowensis. I was in a hurry and at first was not going to try to get it out for fear of damaging it in my rush. But with just a little gently prying with the pick tip on my rock hammer, the specimen popped out quite nicely. Here are some pics of it after I got it home: I then found a palm-sized chunk of solitary rugose coral. I’ve read that a common genus of this coral in this strata is Cystiphylloides, although I have no real basis to ID this as such. I still had about 10 minutes to pry open a few pieces of one of the large, brachiopod-filled rocks and got what I think is a species of Vinlandostrophia, as well as a few, small brachiopods that are not identifiable (to my unskilled eye).

400 Million years in 4 hours The small-scale geology of Austria makes it possible to observe and collect invertebrate marine fossils from a time span of nearly 400 Million years (Ma) within a few hours and at a distance of only about 10 km: - 395 Ma old Devonian (Eifelian) corals - Ölberg - 80 Ma old Cretaceous (Campanian) rudists – St. Bartholomä - 12 Ma old Miocene (Serravallian/Sarmatian) gastropods - Waldhof I did this special hunting trip west of Graz at October 22, 2019 as a "feasibility study". The youngest and oldest fossils can simply be picked from the ground (or photographed); the “middle-agers” require some searching; I succeeded to find a few good specimens within one hour. Weather was perfect with nearly 25°C (!). Simplified geological map of Styria with the visited area west of Graz (red rectangle). Geological map of the visited area (1:50.000), composed of two adjoining map sheets. Red numbers denote visited fossil sites (and their age in Million years). Note the fossil sign in the blue formation in the upper middle of the map. This is the upper Devonian Steinberg-formation with goniatites. These fossils are not abundant, though, so I have never explored this hill… Topo map of the area. Red numbers denote fossil sites, A and B are sites of landscape pics. Just to show off some landscape: View from point “A” in Steinberg towards west. K = Kreuzegg mountain (570 m, Campanian St. Bartholomä-formation) at a distance of ca. 5 km. A = Plateau-like Amering mountain (2187 m, high-grade metamorphic rocks) at a distance of ca. 40 km. View from point “B” at Kreuzegg mountain towards north to southeast. Pano composed of 4 individual pics, spanning about 140°. Labeled mountains and hills in the background are: S = Schöckl (1445 m, Devonian epimetamorphic limestone) at a distance of ca. 20 km. P = Plabutsch mountain (754 m, namesake of the fossil-rich Eifelian Plabutsch-formation) and B = Buchkogel mountain (656 m), both at distance of ca. 10 km and located immediately to the west of Graz. Ölberg and Waldhof sites are between P and B, but not visible. Note the about 1000 m high, largely deforested mountains at the left side of the pano (Mühlberg, Pleschkogel etc., lower Devonian, dolomitic Flösserkogel-formation). The severe deforestation of these hills is due to a strong storm in 2008 (“Paula”). Continued...