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Geology of the Funeral Peak quadrangle, California, on the east flank of Death Valley

1963; United States Government Publishing Office; Linguagem: Inglês

10.3133/pp413

2330-7102

Harald Drewes,

Geological Modeling and Analysis

The 15-minute Funeral Peak quadrangle straddles the ranges between Death Valley and the Amargosa Valley and contains parts of the Black Mountains, Greenwater Valley, and Greenwater Range.A small part of the adjacent Bennetts Well quadrangle is also described; Dantes View and Badwater lie in the northwestern part of the area.The rocks comprise Precambrian metamorphic rocks, Cambrian and Ordovician sedimentary rocks, Tertiary plutonic rocks, and Tertiary and Quaternary volcanic and sedimentary rocks.The oldest Precambrian rocks are schist, gneiss, and marble.These are intruded by diabase of Precambrian age, now metamorphosed to metadiorite.The youngest Precambrian rocks are small remnants of the virtually unmetamorphosed Pahrump series ( ?).In the Funeral Peak quadrangle Cambrian and Ordovician rocks occur only as chaotic structural blocks that are commonly hundreds to thousands of feet long, although the full Paleozoic section in other parts of the Death Valley region is about 4 miles thick.These blocks include parts of many formations and form broken sheets that are at most a few hundred feet thick.Some of these rocks resemble the Noonday dolomite, Sterling quartzite, Wood Canyon formation, Pogonip group, or Eureka quartzite.Other rocks are unidentified dolomites similar to those common among the Cambrian and Ordovician rocks in adjacent areas.Quartz monzonite, porphyritic quartz latite, and porphyritic quartz monzonite of Tertiary age form at least two stocks.The quartz monzonite has a border zone as wide as 2 miles that contains numerous xenoliths.It probably was passively injected into the metadiorite.Primary copper minerals occur only in these rocks or older ones.The other Tertiary and Quaternary rocks comprise widespread and thick older rhyolite and rhyodacite volcanic rocks and sedimentary rocks, locally thick younger rhyolite and rhyodacite volcanic and sedimentary rocks, and still younger more widespread thin andesite and basalt and sedimentary rocks.The older volcanic rocks contain abundant tuff and agglomerate and are intruded by many red felsite bodies.Many felsite bodies contain veins of barite and secondary copper minerals.The younger Copper Canyon formation filled a small basin with more than 10,000 feet of playa and fan deposits, which contain some gypsum and the only identifiable Tertiary fossils found in the area.A similar, but larger, basin was filled with playa beds of the Furnace Creek formation.These beds also contain gypsum, and just northeast of the area they also contain borates.The Greenwater volcanics form several volcanic domes, on the flanks of which vitrophyre flows alternate with pumiceous tuff and conglomerate.A few andesite and basalt dikes and irregular bodies intrude the three older formations at shallow depths, and a few flows connected by a set of northeast-trending faults, lie at the east age (turtleback surfaces) were stripped and then rapidly buried fault since the early Tertiary is at least 4,000 feet and very likely is about 10,000 feet.In response to one of the earlier movements on the fault, some of the folds of Precambrian age (turtleback surfaces) were stripped and then rapidly buried by fan deposits.During a later uplift of part of the Black Mountains block, a large mass from the raised block slid along the turtleback faults across the adjacent fans and into the playa beyond them to form the megabreccia member of the Funeral formation.Further movement along the Black Mountains fault system left the deposits on the turtleback surfaces unsupported.These deposits slid down the turtleback surfaces along the turtleback faults and partly across the Death Valley fault system.Still later movement on this fault system truncated the blocks that slid along the turtleback faults.These movements along the fault system offset the various gravel bodies different amounts.The latest of these movements offset all but the youngest gravel on the fans.VXi/--^ -= §*"" ->W* ~» ^Sv^,, >&v.J3C^r -; ^>^ -. ^ ^^; >-C-'%"^\ >, ASH ^^ ^ <^^-X^>Meafows ^^^? ^Sc^Shoshong ^^j S \ ^s^^| <=s x\ ^""^S.-t-'^TL.recopai