Structure of the Havallah sequence, Golconda allochthon, Nevada: evidence for prolonged evolution in an accretionary prism.

The Golconda allochthon of northern and central Nevada contains the Havallah sequence and correlative units of latest Devonian to early Late Permian age. The Havallah sequence is dominated by radiolarian ribbon chert and argillite. The Havallah sequence was thrust eastward along the basal Golconda thrust onto coeval sediments of the W North American shelf during the latest Paleozoic-earliest Mesozoic Sonoma orogeny. Structural fabrics are described in detail and the classical Sonoma orogeny (D₃) may mark the culmination of a protracted structural evolution that may have spanned much of the upper Paleozoic.-after Authors