The Sonomia Terrane is a geologic
crustal block known as a "
terrane
In geology, a terrane (; in full, a tectonostratigraphic terrane) is a crust fragment formed on a tectonic plate (or broken off from it) and accreted or " sutured" to crust lying on another plate. The crustal block or fragment preserves its ow ...
" whose remnants today lie in northwest
Nevada
Nevada ( ; ) is a state in the Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the 7th-most extensive, ...
. The terrane acquired its name from the
Sonoma Range
The Sonoma Range is a small mountain range in northwest Nevada
Nevada ( ; ) is a state in the Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the so ...
in that region. The Sonomia Terrane is associated with the
Golconda Thrust
The Golconda Thrust is a major oceanic terrane that was thrust over central and northern Nevada, North America, in possibly sometime between the Late Permian and the late Jurassic. It is considered equivalent to the Tobin thrust fault.
It conta ...
, a structure named for its proximity to the town of
Golconda, Nevada
Golconda is a census-designated place in southeastern Humboldt County, Nevada, United States. As of the 2010 census it had a population of 214. It is located along Interstate 80 on the Humboldt River in the northwestern part of the state. Gol ...
. The
Sonoma orogeny The Sonoma orogeny was a period of mountain building in western North America. The exact age and structure of the Sonoma orogeny is controversial. The orogeny is generally thought to have occurred during the Permian / Triassic transition, around 250 ...
was caused by the
accretion
Accretion may refer to:
Science
* Accretion (astrophysics), the formation of planets and other bodies by collection of material through gravity
* Accretion (meteorology), the process by which water vapor in clouds forms water droplets around nuc ...
of the Sonomia
microcontinent
Continental crustal fragments, partly synonymous with microcontinents, are pieces of continents that have broken off from main continental masses to form distinct islands that are often several hundred kilometers from their place of origin.
Caus ...
onto western North America during the mid-
Triassic
The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago (Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period ...
.
References
Geology of Nevada
Terranes
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