Big Maria Mountains

Big Maria Mountains
Mountain Range
Country	United States
State	California
District	Riverside County
Coordinates	33°51′0.067″N 114°42′2.865″W
Highest point
- elevation	324 m (1,063 ft)
Timezone	Pacific (UTC-8)
- summer (DST)	PDT (UTC-7)
Topo map	USGS Big Maria Mountains SW
location of Big Maria Mountains in California

The Big Maria Mountains are located in the southeastern part of the U.S. state of California, near the Colorado River and Arizona. The range lies between Blythe and Vidal, and west of U.S. Route 95 in California. The mountains are home to the Eagle Nest Mine and reach an elevation of 1,030 meters, (3,379 ft). A power line that runs from Parker Dam to Yuma, Arizona runs through the range. A smaller range, the Little Maria Mountains, lie to the west of the Big Marias.

Geology

The Big Maria Mountains are one of several ranges that constitute the Maria Fold and Thrust Belt. The Maria Fold and Thrust Belt underwent generally thick-skinned (involving basement rocks) North-South trending crustal shortening in the Cretaceous. The structures of the MFTB are exposed by to later generally East-West trending large-scale crustal extension in the Miocene, through what is known to geologists as the Colorado River Extensional Corridor

This North-South shortening is anomalous, as crustal shortening in the rest of the North American Cordillera is oriented generally East-West because of the generally East-West compression that was due to the subduction of the Farallon plate under western North America. Also unlike the rest of the North American Cordillera, deformation in the Maria Fold and Thrust Belt involved rocks of the North American Craton, most notably the Grand Canyon sequence of sedimentary rocks.

Big Maria Mountains Wilderness Area

The Big Maria Mountains Wilderness Area is managed by the Bureau of Land Management for recreation and nature reserve protection.

The terrain of the Big Maria Mountains varies from gently sloping Alluvial fans-bajadas to numerous rough, craggy peaks disjointed by steep canyons. The northern boundary lies south of a major drainage known as Big Wash, and the eastern edge parallels U.S. Route 95 in California and the Colorado River. The west and south boundaries follow power lines and contours along the base of the mountains. Foxtail cactus and California barrel cactus dot the landscape, and a Burro deer herd relies on the river's habitat for survival.

Rice Valley Wilderness Area

The Bureau of Land Management also manages the Rice Valley Wilderness Area in and near the Big Maria Mountains.

The broad, flat plains of Rice Valley and the northwestern tip of the steep and rugged Big Maria Mountains lie within the borders of this wilderness. A system of small dunes rising 30 to 40 feet above the surface form a long, narrow band running through the middle of the valley floor. The valley is part of a massive Erg-sand sheet which extends from Cadiz Valley through Ward Valley, representing a part of one of the largest dune systems in the Desert Region of California. The Big Maria Mountains rise above the valley to an elevation of 2,000 feet.

See also

• Little Maria Mountains

• Category: Fauna of the Colorado Desert
• Category: Flora of the California desert regions
• Category: Wilderness Areas within the Lower Colorado River Valley
• Category: Protected areas of the Colorado Desert
• Category: Mountain ranges of the Colorado Desert

External links

• Official Big Maria Mountains Wilderness Area website
• BLM Big Maria Mountains Wilderness Map

• Official Rice Valley Wilderness Area website
• BLM Rice Valley Wilderness Map
• Rice Valley Wilderness Area photographs