Mark Wilson April 8th, 2014
MITZPE RAMON, ISRAEL–This afternoon I walked through the spectacular Middle Triassic sections in Wadi Gevanim on the southern side of the Makhtesh Ramon structure. I will be on a fantastic trip this Thursday to a little-visited Triassic section farther south, so I wanted to refresh my memory of these units. The above image is looking north from Wadi Gevanim to Mitzpe Ramon just visible on the cliff edge of the makhtesh. (What a setting, eh?)
I found myself almost completely repeating an entry from last year on Wadi Gevanim (which had the added bonus of students in it). Today I gathered some impressive fossil cephalopods from the Saharonim Formation (Middle Triassic, Anisian-Ladinian) for a group photograph. I note only now that one of the nautiloids above appears last year as well! From the upper left going clockwise: nautiloid, ammonite, nautiloid, ammonite. All are internal molds (the outer shell has been removed).
That upper left nautiloid is worth a closer look. The mold has been split down the middle showing the septa (internal walls dividing the chambers) and an impressive “beaded” siphuncle (connecting tube) running the length of the conch (shell).
Finally, here is a handful of the common terebratulid brachiopods from the Saharonim. Speaking of which, have I mentioned the species Menathyris wilsoni from the Saharonim? You certainly must meet Menathyris wilsoni!