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Full-Text Articles in Physical Sciences and Mathematics
The Geology And Structures In The Northern Hiko Range, Lincoln County, Nevada, Douglas D. Switzer
The Geology And Structures In The Northern Hiko Range, Lincoln County, Nevada, Douglas D. Switzer
UNLV Theses, Dissertations, Professional Papers, and Capstones
In the northern Hiko Range, extension occurred in four temporally distinct episodes during the Cenozoic. The extensional events are (1) prevolcanic (> 27.31 ± 0. 03 Ma), (2) syn-volcanic (between 22.78 ± 0,03 and 18.5 ± 0.4 Ma), (3) Tertiary(?) post-volcanic ( < 14.7 ± 0.4 Ma), and ( 4) Pliocene(?) - Quaternary. Four fault sets are delineated based on orientation and cross-cutting relationships: (I) northeast- to northwest-striking moderately dipping prevolcanic faults, (2) east-west striking, steeply-dipping syn-volcanic faults, (3) east-west- and east-northeast-striking, steeply dipping Tertiary(?) post-volcanic faults, and (4) generally north-striking steeply dipping Pliocene (?) - Quaternary faults.
Prevolcanic faults in the northern Hiko Range are interpreted to be footwall faults to an Oligocene age extensional system. These faults increase the area affected by Oligocene extension and support existing evidence that suggests this event is widespread.
A tectonomagmatic rift model has been proposed to explain synvolcanic extension during the Tertiary in the northern Basin and Range …
The Petrogenesis Of Andesites Produced During Regional Extension: Examples From The Northern Mccullough Range, Nv And Xitle Volcano, Mexico, Kelly Ann Boland
The Petrogenesis Of Andesites Produced During Regional Extension: Examples From The Northern Mccullough Range, Nv And Xitle Volcano, Mexico, Kelly Ann Boland
UNLV Theses, Dissertations, Professional Papers, and Capstones
Andesite dominated volcanic systems produced during regional crustal extension remain a relatively unexplored aspect of andesite petrogenesis. In the southern Basin and Range province, thick sections of andesite and basaltic andesite have been documented in areas including the Piute Range, California, the Eldorado Range, Nevada, and the McCullough Range, Nevada. The northern McCullough Range, located 20 miles south-southeast of Las Vegas, is an ideal place to study the petrogenesis of an andesite dominated system. This area contains a mid-Miocene stratocone composed mainly of a 1200 m thick section of andesite flows that formed synchronous with regional extension.
The northern McCullough …