Minerals in the Mesas

Minerals in the Mesas. Local Prospects. , Dakota Formation’s Coal and Clay , While the rock formations in this region often presented formidable travel obstacles for early settlers, they also supplied many useful natural resources. Locally, a rock layer known as the Dakota Formation (the bottommost layer of which is just visible atop the colorful Entrada sandstone cliffs before you) yielded two important resources , coal and bentonite clay. , Created from the remains of lush, coastal swamps that covered this region more than 80 million years ago, thin coal seams in upper Bryce Valley sustained a handful of small mining operations that supplied heating fuel to area residents during the 1900s. In the mid-1900s, bentonite clay was also mined about a mile east of here. Bentonite clay can absorb many times its volume in water, a quality that has led to its use in many applications , from water storage and well drilling to cat litter and medicines. , Bentonite , In the late 1930’s, a Henrieville mine yielded thousands of tons of bentonite from these hills. Much of the bentonite was trucked to the Glen Canyon Dam site, where it was used to build a coffer dam that diverted the river so the main dam could be built. To facilitate transport, local men donated time and machinery to complete the Cottonwood Road from Cannonville to Route 89., Coal Mining , In the early 1900s, a small coal mine opened about two miles from here, where local residents could buy hand-dug coal for their stoves. During the 1940’s, the Shakespear mine near Tropic used dynamite to blast the coal seams, and miners hauled out the coal with horse-drawn trailers. . This historical marker is Near Henrieville in Garfield County Utah