Is There Oil in Your Backyard?
The United States - West
Above: All of the regions that have produced oil
and natural gas in the Western United States
Most of the petroleum in the West (including CA, NV, OR, and WA) occurs in California. Nevada produces very little oil, and the main fields are in the eastern central section of the state (including the most productive, the Eagle Springs Field.) Oregon is predominantly volcanic rocks resulting from development of the Cascade Range and fissure eruptions that created the lava plateaus of eastern Oregon. Although there are sedimentary rocks in the coastal belt and the Willamette Valley, there is little oil potential. Washington, likewise, for the most part has little oil potential except within the Olympic Peninsula and coastal areas north of Grayland. Active seeps on the western section of the peninsula result from Tertiary coal bearing sandstone reservoir rocks. Environmental concerns have limited exploration and drilling on the Olympic Peninsula. There has never been any large-scale commercial oil or gas production in Washington, however, the Puget Lowland and Columbia River basin have natural gas potential.
California's vast oil production is the result of several large sedimentary basins, complex geology creating significant traps, and more recently, the development of large offshore oil fields. Oil has long been a part of California's economy: as early as the 1500's, Spanish explorers saw Indians using asphalt from oil seeps, and in 1855 (four years before Colonel Drake drilled America's first oil well in Titusville, PA) oil from a seep was sold in Humboldt County. The Los Angeles Basin has the most productive fields in the state. California's oil formed predominantly during the late Tertiary period.
Despite the high production in California, the state consumes more oil than it produces. Over the last several decades there has been increasing tensions between the booming population (particularly of Southern California) and the development and production of oil fields located in the midst of population centers (such as the Los Angeles Basin).
Offshore wells were first drilled in the U.S. in 1896 off the Santa Barbara County coast. Future West coast exploration and production of conventional oil and gas fields will also most likely be off California's coast. Unconventional oil resources also significant to the region include California's tar sands and diatomaceous shale, which may also help meet future production needs.
Below: Some of the sedimentary basins in the West region of the United States. Compare this illustration with the one at the top of this page to see which sedimentary basins have produced the most petroleum, and which ones have produced none.
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1-Sacramento Valley Basin |
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