The 45 km 2 map area is situated at the south end of the Hot Creek Range in central Nevada, ~16 km east of the buried leading edge of the Mississippian Roberts Mountains thrust. Three eastward-trending left-slip faults divide the area into four structural blocks. The southernmost block is occupied solely by upper Oligocene volcanic rocks. The narrow northernmost block, now occupied surficially by valley fill and volcanic rocks, represents the south end of the main part of the Hot Creek Range, from which the study area is offset. The middle two blocks display different aspects of the eastward-traveled outer crater rim created by the ca. 382 Ma (early Late Devonian, middle Frasnian) Alamo impact. The Alamo impact was produced by a 5-km-diameter bolide, most likely a comet, which excavated a transient submarine crater 44–65 km in diameter. Comparison of thin (8–12 m) Alamo Breccia deposits in the northern of the middle two blocks with a more easterly, thick (35–42 m) Alamo deposit in the main Hot Creek Range, 4 km north of the map area, suggests that these blocks traveled many kilometers eastward. The northern of the middle two blocks contains a large olistolith capped by the thin breccia, whereas the southern block contains a larger olistolith lacking an Alamo Breccia cap. Three Devonian pulses of the Antler orogeny are better documented in the chapter on the Bisoni-McKay area. Here, the first Antler pulse in latest Middle Devonian time is obscured within an ~9 m.y. hiatus enlarged by excavation of the Alamo impact crater. The second Antler pulse is recorded by the ~4 m.y. hiatus produced by the regional unconformity between the lower and upper members of the Woodruff Formation. The third Antler pulse is documented by an ~8 m.y. regional hiatus between the Mississippian Webb Formation and Upper Devonian Woodruff Formation. In previous papers, we had interpreted this pulse to initiate the Antler orogeny.

Abstract There are three large intracratonic basins (Vindhyan, Cuddapah and Chattisgarh) and several smaller basins (Kaladgi, Bhima, Pakhal, Penganga, Indravati, Khariar, Sabari and Kolhan) covering a large part of peninsular India. They are not known to host any significant metallic resource – except for a substantial uranium resource and Pb–Zn sulphide mineralization in the Cuddapah Basin, uranium in Bhima and Kaladgi basins and manganese in the Penganga sequence – but are nevertheless the repository of vast resources of industrial rocks (limestone, dolomite, phosphorite, aluminous laterite, building materials) and minerals (including pyrite, barite and diamond) in the country. The temporal distribution of these resources indicates a Mesoproterozoic age for all the deposits and occurrences except the uranium deposits in the Vempalle dolostones in the southwestern fringe of the Cuddapah Basin, which are Palaeoproterozoic in age. The Cuddapah Basin is the most intensely mineralized Proterozoic basin, with the Cumbum Formation in the Nallamalai belt hosting stratabound base metals and barite, dated c. 1.6 Ga, all the way from north to south. Potential mineralization, still undiscovered in the basin, is a large SEDEX-type Pb–Zn orebody in the vicinity of the Mangampet barite deposit and unconformity-proximal U deposits in the Kurnool Group, similar to those of the Bhima Basin.