Boring Lava Field

The Boring Lava Field is an extinct Plio-Pleistocene volcanic zone with at least 32 cinder cones and small shield volcanoes lying within a radius of 13 miles (21 km) of Kelly Butte, which is approximately 4 miles (6 km) east of downtown Portland, Oregon, in the United States. The name is derived from the town of Boring, Oregon which lies just to the southeast of the most dense cluster of lava vents. The zone became active at least 2.7 million years ago, and has been extinct for about 300,000 years. [http://vulcan.wr.usgs.gov/Volcanoes/Oregon/BoringLavaField/description_boring_lava.html USGS Information page for the Boring Lava Field] ]

The Portland metropolitan area, including suburbs, is one of the few places in the continental US to have extinct volcanoes within a city's limits; Bend, Oregon is another.Fact|date=August 2007

Oregon vents

The following vents are in Oregon:
* Chamberlain Hill - Elevation 980 ft (299 m)
* Cook's Butte - Elevation 718 ft (219 m)
* Kelly Butte - Elevation 590 ft (180 m) (near the interchange of SE Powell Boulevard and I-205 in Portland)
* Mount Scott - Elevation 1,050 ft (320 m) (named for Harvey W. Scott)
* Mount Tabor - Elevation 641 ft (195 m) (center of a large multi-use Portland city park)
* Larch Mountain - Elevation 4,055 ft (1,236 m)
* Mount Sylvania - Elevation 958 ft (292 m)
* Powell Butte - Elevation 620 ft (189 m)
* Rocky Butte - Elevation 612 ft (187 m) (stone tower with outstanding view of Portland)
* Ross Mountain - Elevation 1,380 ft (421 m)
* Swede Hill - Elevation 995 ft (303 m)
* TV Hill - Elevation 1,275 ft (389 m)
* Walker Peak - Elevation 2,450 ft (747 m)
* Highland Butte - Elevation 1,594 ft (486 m) (near Beavercreek, Oregon)

Washington vents

The following vents are in Washington:
* Battleground Lake - Elevation 750 ft (229 m) (miniature crater lake)
* Bob's Mountain - Elevation 2,110 ft (643 m) (contains intact summit crater)
* Brunner Hill - Elevation 680 ft (207 m)
* Green Mountain - Elevation 804 ft (245 m) (logged off during the First World War)
* Mount Norway - Elevation 1,111 ft (339 m)
* Mount Pleasant - Elevation 1,010 ft (308 m)
* Mount Zion - Elevation 1,465 ft (447 m)
* Nichol's Hill - Elevation 1,113 ft (339 m)
* Pohl's Hill - Elevation 1,395 ft (425 m)
* Prune Hill - Elevation 610 ft (186 m) (overlooks Camas, Washington)

Map

* [http://vulcan.wr.usgs.gov/Volcanoes/Oregon/Publications/Allen1975/boring_lava_allen_table.html USGS Map of Boring Lava Field]

References