The bedrock in the valleys of the park consists of the Upper Devonian Catskill Formation, consisting of sequences of sandstone, siltstone, and shale.
The Burren comprises dramatic karst landscapes on Ireland’s Atlantic coast which have been fashioned in a variety of limestones, sandstones and siltstones originating during the Carboniferous period.
The Cleveland Ironstone Formation is a sequence of marine ironstone seams interbedded with shale and siltstone units which collectively form a part of the Lower Jurassic System of rocks underlying Cleveland and North Yorkshire.
It was discovered and collected in the tuffaceous siltstones and mudstones of the lower part of the Hanson Formation, in Mount Kirkpatrick.
About its late Whaingaroan (about 27 million years ago) creation, it says, “The change from estuarine, shallow brackish water conditions (Mangakotuku Formation), to fully marine, open sea, aerobic conditions (Glen Massey Formation) is evidenced by near shore accumulation of the bioclastic Elgood Limestone, onlap of the succeeding Dunphail Siltstone, and subsequent deposition of Ahirau Sandstone in an inner to mid shelf environment.”
Simocetus is known from a single fossil, a skull, found in marine siltstone deposits of the Alsea Formation on the banks of Oregon's Yaquina River in 1977 by fossil hunter of the region, Douglas Emlong.