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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.

I have studying ammonite anatomy and nomenclature as well as the local geology where I have been hiking. Today I rough prepared several ammonites and feel like I can make an educated attempt to name 2 of 3 that I worked on. I am reasonably certain they are from member three of the Matanuska Formation in the Talkeetna Mountains. I have shared some pictures of where I found one on the snow at the bottom of an avalanche so pictures of that one first as it is new to me. In my effort to learn these will describe why I believe it is Gaudryceras tenailiratum; wide umbilicus, course ribs, rounded venter, pattern of major rib separated with repeating pattern of secondary ribs, the ribs are asymmetrical with the anterior side sloping in concave slope and the slopes abruptly. I did not prepare the back side as it was a double and left the mold from the other ammonite as I think it pretty cool. The next one also is ribbed and I believe is Neophylloceras ramosum and base that decision on the pictures from the Gological Survey Professional Paper 432 as well as the description. I have seen these one many times and have a few in the garden. I found that prepping them I have become quite attached as it takes time and learn the morphology as cleaning the fossil. This one had several shells in the matrix and I left a portion of one. Will make another post for the third ammonite Thanks in advance for any helpl!!!

My 9 year old boy found several of these on the side of a hill near gun sight mountain Alaska. The area is know for sea shell fossils, we found several clam shells in the same area. This is right in the middle of the Matanuska formation.