Author Description

Abstract: Throughout the Roberts Mountains in north-central Nevada, southern Eureka County, large carbonate masses form topographic highs above structurally thick packages of siliciclastic strata of the Roberts Mountains allochthon. During the Late Devonian-Early Mississippian Antler orogeny, the Roberts Mountains thrust emplaced the Roberts Mountains allochthon upon an equally thick coeval carbonate succession. A recently discovered post Antler-thrust fault, the Henderson thrust, duplicated the Roberts Mountains allochthon and in doing so plucked large carbonate masses from the carbonate succession underlying the Roberts Mountains thrust and emplaced them to the east above a great thickness of the Roberts Mountains allochthon. The carbonate masses are referred to as tectonic erratics. Such a large carbonate mass may occur at Mineral Hill 40-kilometers northeast of the Roberts Mountains. A brecciated thrust fault extends the entire 6-kilometer length of Mineral Hill on the east margin. In southern Mineral Hill, carbonates are underlain by siliciclastic strata of the Roberts Mountains allochthon along the thrust fault. The carbonate beds dip at a high angle into the shallow dipping thrust fault. The siliciclastic strata immediately east of Mineral Hill are highly deformed