geothermal resource potential of the safford-san simon basin, arizona

stress fields may dilate some of these structures where they are oriented
favorably.
The Morenci lineament direction correlates with the northeast direction
of major Precambrian structures in Arizona.
Oldest of the Precambrian rocks,
the Pinal Schist, is believed to represent major northeast-trending regional
structural deformation (Silver, 1978).
Near the trace of the Morenci lineament
in northwest Cochise County, the Pinal Schist is highly deformed and forms
a large (40 km) wide "anticlinorium" exhibiting strongly overturned folds
(Silver, 1978).
Pinal Schist.
Precambrian granite and granodiorite plutons intrude the
Similar intense deformation is seen in the crystalline rock
of the Pinaleno Mountains.
It should be noted, however, that the Pinaleno
Mountains are a part of a Tertiary "metamorphic core complex" which overprints
the Precambrian deformation (Davis and Coney, 1979).
In the Stockton Pass area, Swan (1976) presents geochronologic data
that suggests that the Texas Zone features originated between 1,400 m.y.
and 1,200 m.y.
In Stockton Pass, Swan (1976) maps a wide zone of west-northwest
trending faults which left-laterally displace Precambrian diabase intrusions
in granitic plutonst
Due to tectonic reactivation after 1100 m.y.
Paleozoic rocks are not believed to be widely present in the subsurface
in the Safford-San Simon basin because erosion, subsequent to Mesozoic and
Tertiary tectonism, has probably removed these rocks, although isolated and
incomplete sections of Paleuzoic rocks may occur.
Zenoliths of quartzite
(Cambrian-Ordovician Coronado Sandstone?) are observed in Laramide intrusions
in the Gila Mountains (Dunn, 1978). East of the study area, a Mesozoic uplift
is centered in the Burro Mountains, New Mexico.
Elston (1958) names
this post-Permian, pre-late-Cretaceous feature, the Burro uplift.
North of
Burro uplift progressively older Paleozoic rocks are observed in outcrop as
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