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I went on a hunting trip this August in the Arctic National Wildlife Refuge of northern Alaska. This was in the Brooks Range which was mainly composed of limestone in the 2 areas we hiked. Our base camps were setup with aircraft tied down, bear fence around camp and all food in bear proof containers when we left on the hikes. Fossil corral was present in all the river bars we traversed. Hash block with shell material. Stromatoporid fossils were abundant. Dall sheep ram tracks. Crinoid Cotton grass and cloud berries at 4,500 elevation meadow. Ewe sheep crossing the meadow after we did. The first 4 days of the trip was hampered by smoke from fires burning in the Yukon Territory, Canada. We camped in the same meadow and awoke to no smoke and fog the rolled in from the coastal plane over night. I was constantly examining the abundant fossils on this trip which was a big part of my enjoyment. It would be interesting to know time it took for the limestone to be etched from this corral. There is liquid water maybe 4 month of the year at this latitude and elevation. The limestone cap rocks erode vertically leaving these dramatic land forms. These stromatoporid fossils were present in all areas we traversed. Most common were the black forms of various ovoid and loculated shape. Dall sheep rams below where we camped one evening. Sheep in camp the following morning. More amazing land forms from the on end limestone. Fossil corral eroding slower than the limestone. The whole scree slope had pieces of corral in the limestone. A massive landslide with some blocks of limestone being bigger than most homes. This area is part of the Porcupine caribou herd and had trails used for 100's of years cut into the mountains. Parka squirrel as the natives call them, used to make winter parkas in the past. Last one, shell fossils were uncommon and when I saw them heavily metamorphized. For the hunters we saw 27 rams and elected to harvest none as no older ones located in 10 days of hiking.

The hike started with a group photo with Kobuk and a band of Dall sheep, ewes with lambs. Appropriate start to the hike as the Greek ram horned god called Ammon is the basis for the name ammonite. I returned to an exposure I had visited in the past that was particularity steep with new boots to safely negotiate the steep siltstone. The geology is Matanuska Formation member 3 which I have posted some trips in the past. Multiple new ammonites had been exposed with many molds present and some of the ammonites already lost to erosion being washed down to the bottom gully where they break into bits. This was a double mold. A view of the bottom shows multiple fragments and pieces of shells. Bivalve fossils were evident with these two being mostly intact. I am going to put names on some that I believe are correct and would like confirmation or corrections from the group. 1) Pachydiscus hornbyense Traversed across here leaving my pack to make my steps more nimble. Pictures follow of what was readily visible. 2) The top one is Neophylocerus ramosa, hard to see in the picture but in is finely ribbed and involute with past experience of finding these here before am confident with this ID. This ammonite caught my eye and after cutting foot steps worked at exposing it. 3) Once exposed removed the matrix tentative ID: Packydiscus sp. It is still in the mountains so this is the only pictures I have of it. This view gives an idea of how steep the terrain is here. Falling is not an option. I have posted pictures of this ammonite in the past and it is getting close to its final ride. Another starting to pop out. This one was precariously perched on the concretion. Once they hit the bottom not much is remaining from the impact. 4) An uncommon treat, a heteromorph. Nostroceras sp. ? A double from one concretion. will have to clean the matrix of figure out what they are. 5) Another pair in close proximity. Pachydiscus sp. Ammonite grave yard. Parting view of the sheep overlooking the guy with orange boots on. Back to the Cub and the new boots are no longer new.