DESCRIPTION:
Battle Ground Lake, Washington
Battle Ground Lake State Park

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Topo Map, Battle Ground Lake, 1:25,000

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USGS Aerial Photo, Battle Ground Lake, 1990

The lake's origin is volcanic, and is believed to have been formed as a "Maar" volcano. This type of volcano is the result of hot lava or magma pushing up near the surface of the earth and then coming into contact with underground water. This is thought to have resulted in a large steam explosion, leaving a crater that later formed a lake.

This area was named for a battle that settlers at Fort Vancouver expected to happen in 1855 between U.S. Army soldiers and some Klickitat Indians. The battle never occurred. Captain Strong, the post commander, allowed some Indians to leave the fort on the promise that they would return after burying their chief, who had been accidentally killed. Most fort residents believed a battle would ensue to get the Indians to return, and therefore dubbed the spot "Strong's Battle Ground." The Indians, true to their word, returned peacefully, but the name took hold. Later the area was simply referred to as "Battle Ground."

Maar Volcanoes Menu

Visit A Volcano - Battle Ground Lake State Park

Metropolitan Portland, Oregon, like Auckland, New Zealand, includes most of a Plio-Pleistocene volcanic field. The Boring Lava includes at least 32 and possibly 50 cinder cones and small shield volcanoes lying within a radius of 21 kilometers (13 miles) of Kelly Butte, which is 100 kilometers (62 miles) west of Mount Hood (Oregon) and the High Cascade axis -- (Web note: Kelly Butte is approximately 4 miles east of downtown Portland, Oregon). Only the Clear Lake volcanics in California lie as far west in the coterminous United States. Unlike Clear Lake, Boring lava vents have been inactive for at least 300,000 years. ...

Partial summit craters remain only at Bobs Hill, 33 kilometers (20.5 miles) northeast of Portland, and at a low cone enclosing a lake north of Battleground, Washington, 33 kilometers (20.5 miles) north of Portland. Most other volcanoes still have a low cone shape and are mantled with loess above 122 meters (400 feet) elevation. Below this they were scoured by the cataclysmic Bretz floods from Glacial Lake Missoula around 13,000 to 15,000 years ago. Boring lava is characteristically a light-gray phyric olivine basalt. A specimen from Rocky Butte is predominantly labradorite, with phenocrysts of olivine, mostly altered to iddingsite. The volcanoes locally contain scoria, cinders, tuff, tuff breccia, and ash. Weathering may extend to depths of 8 meters (25 feet) or more, the upper 2-5 meters (5-15 feet) commonly being a red clayey soil.

Boring Lava Field Menu

Boring Lava

The Boring Lava of Treasher (1942) forms many basaltic eruptive centers in the Portland basin (Trimble, 1963; Mundorff, 1964). It is represented in this quadrangle by a field of olivine basalt flows and cinder cones mapped as the basalt of Battle Ground (Qb). At least three vent sites for the basalt of Battle Ground can be identified: two cones of basalt scoria (Qbs) mapped in this quadrangle, and the Battle Ground Lake maar crater 2 km southeast of them, beyond the quadrangle. New dating from a flow derived from the northern cone and from a dike or flow exposed in the maar establish the age of the basalt of Battle Ground as about 0.1 Ma (R. Fleck, unpub. data), making it among the youngest rocks of the Boring Lava (Conrey and others, 1996).

Qb - Basalt of Battle Ground (upper Pleistocene)

Vesicular, gray to black, diktytaxitic, fresh olivine basalt, weathered to soil in upper part. Two flow units with massive centers and vesicular flow tops exposed on bluff above East Fork Lewis River. Correlated with Boring Lava of Treasher (1942). Thickness up to 40 m for flows and up to 60 m including basalt scoria subunit (Qbs) at cinder cones. Age 0.1 Ma based on preliminary ages using ⁴⁰Ar/³⁹Ar method (R.Fleck and R. Evarts, oral commun., 2000, 2001): about 107 ka at northernmost outcrop overlooking East Fork Lewis River (NE1/4 SE1/4 sec.14, T.4N., R.2E.) and 99 +/- 57 ka where exposed in Battle Ground Lake maar crater 0.5 km east of quadrangle; that crater contains sediment at least 20 ka (Barnosky, 1985). Also includes:

Qbs - basalt scoria

Red to gray; highly vesicular; includes agglutinate in SW1/4 NW1/4 sec.24, T.4N., R.2E. Forms steep hills, evidently cinder cones. Locally described in well log as multicolored pumice. Buttresses against bouldery glacial drift (NE1/4 SE1/4 sec.24, T.4N., R.2E.)

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