| Southeast Oregon Basin and Range Area/Range |
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| Southeast Oregon Basin and Range   | 
| Page Type: Area/Range Location: Oregon, United States, North America Lat/Lon: 42.38600°N / 119.3307°W Elevation: 9733 ft / 2967 m | Page By: calebEOC Created/Edited: Nov 12, 2007 / Aug 5, 2008 Object ID: 355999 Hits: 2770 Loading... Page Score: 90.04% - 22 Votes Loading... Vote: Log in to vote |
Basin and Range
Southeast Oregon is defined by north-south trending ranges, steep walled valleys, and isolated buttes. This land of Basin and Range is the result of the east west extension of the Earth's crust. As Western Oregon is pulled away from the eastern half of the state, the continental crust is fragmented into massive blocks that primarily behave in three ways: they lift leaving isolated ranges such as Hart Mountain; plunge leaving deep flat valleys such as the Alvord Desert; or tilt which results in a soaring cliff on one side and a gradually descending flank on its opposing side. This last instance is best seen at Abert Rim, with a 2500 foot cliff on its west flank, and a 1500 foot dropoff over the course of 20 miles on its gradual east side. Although basin and range is isolated to the southeast corner of the state in Oregon, it is quite common across the American Southwest and can be seen most notably along the east edge of Death Valley, itself a fault block plunge. The picture below to the right explains Fault Block Terrain, this sign can be found at a rest stop alongside highway 395 at Abert Rim. Viewing the image at original size may make it easier to read.
Buttes
Another highlight of Southeast Oregon is its many buttes, perhaps chief among these is Beatys Butte on the west side of the Catlow Valley near Steens Mountain. A sign of long ago volcanics, these one time lava cones and volcanoes are found at varying heights and masses across southeast Oregon. Glass Buttes near the settlement of Hampton is comprised of large amounts of multi-colored obsidian and is a popular site for rock-hounds. Watching over the small settlement of Wagontire Oregon is a trio of small but distinctive peaks visible from miles away; 5300 footers Iron Mountain, and Squaw Butte, and the larger 6513 foot Wagontire Mountain. Far to the west near Egli Rim lays Table Rock, a small but distinguished flat-topped butte. Many of these buttes unknown or unrecognized by hikers provide great beauty to the flat desertlands and reveal a variety of animal and plant life not found in the lower basins.
Flood Basalts:
Roughly 17 million years ago across much of Eastern Oregon, fissures in the Earth's crust erupted tremendous amounts of basaltic magma inundating much of the Pacific Northwest. Signs of these flood basalts can be found along the rangetops of Southeast Oregon, most notably along the rim of Abert Rim and the east face of Steens Mountain, both of which are nearly entirely comprised of flood basalts. Steens Basalt erupting from vents near Pueblo Mountain left a layer of basalt over 3000 feet thick in places along the Steens Mountain uplift.Notable UpliftsSteens Mountain:
At nearly 10000 feet, glacially articulated Steens Mountain is the best known of the fault uplifts in southeast Oregon. This massive fault block tilted to its west, leaving a high eastern rim with a 9733 foot summit, that gradually descends northwesterly towards the Malheur Lake Basin near the town of Burns. To the east of Steens Mountain is the Alvord Desert, a block that has plunged leaving a 7000 foot offset between the lowest point of the Alvord Desert Block (deep beneath the sediments of Alvord Lake) and the summit of Steens Mountain. To the southeast is the soaring walls of the Catlow Rim carved with canyons from ice age runoff into a vast inland lake that occupied the presently dry Catlow Valley. Evidence of this lake can be seen along the east side of the Catlow Valley and its many sand dunes. Seen in the image at left is Big Kiger Gorge from the Kiger Gorge overlook. On the horizon is the peak known as KigerMann highlighted by the notch, where a glacier once breached the summit ridgeline of Steens Mountain. At the southern termination of the Steens Mountains is Alvord Peak.
Pueblo Mountain:
The Steens Mountain Range extends south towards The Peaks and Pueblo Mountains. The Pueblo Mountains which geologically are a seperate plate from the Steens are a natural extension of that massive mountain range. It is believed the oldest visible rock in Oregon can be found in the Pueblos, where uplift and plunging fault blocks have exposed rock from deep within the Earth's crust. The highpoint of this uplift is Pueblo Mountain at 8725 feet, one of Oregon's least visited high elevation buttes.
Hart Mountain:
Hart Mountain, a flat-topped uplift is protected on all sides by steep sided cliffs which are broken by deep gorges. Hart Mountain is best known for its status as a federally protected antelope refuge, and as such is home to large antelope and bighorn sheep populations. To the north of Hart Mountain extends Poker Jim Ridge and the Orejana Plateau. Atop the Hart Mountain plateau are the Warner and Hart subpeaks barely rising from its long flat summit. Although Warner Peak is little more than a bump on massive Hart Mountain it is recognized as a 2000 foot prominence peak. Hart Mountain is the entire uplift seen in the image below taken from the North Shore of Hart Lake.
Drake Peak:
At 8407 feet in height, this conical mountain is located directly between the Abert and Lynch Rim uplifts. Drake Peak is the highpoint in a small cluster of high elevation peaks including Light, Twelvemile, McDowell, and Crook Peaks, all over 7600 feet in height. Drake Peak is seen in the image below to the right. Light Peak is the highest point on the left.
Crane Mountain:
The highpoint of the Warner Mountains in Oregon at 8456 feet. The Warner Mountains are a massive uplift overlooking Goose Lake, a large alkaline lake crossing the Oregon-California border. The Goose Lake Basin and Warner Mountains extend far into California where the range's highpoint is Eagle Peak at 9892 feet in the South Warner Wilderness.
Abert Rim:
North America's longest fault escarpment. Topping out at 7543 feet, Abert Rim stretches non-directly over 40 miles from the Sherman Valley near Drake Peak far north to the Christmas Valley - Wagontire Cutoff Road. While nearly all of Abert Rim's nearly vertical west face could be considered desert, its gradual east face hides a large ponderosa forest referred to as Colvin Timbers.Other Fault UpliftsWinter Ridge: A large uplift ravaged by the Winter Fire in 2002. The highpoint of Winter Ridge is 7762 foot Slide Mountain at the southeastern end of the rim. Freemont Point near the mid-point of Winter Ridge can be driven to is a popular viewpoint overlooking the Summer Lake Basin. Below, Winter Ridge as seen from the west shoreline of Summer Lake.
Lynchs Rim: A distinctive rim seen along the Adel - Plush Highway. This rim rises 2000 feet from Crump Lake to its highest point less than one mile to the west. No developed trails exist to the summit of Lynchs Rim as most of the summit plateau is private ranchland. Below; Lynchs Rim as seen from Crump Lake.
Egli Rim: Notable as the first obvious rim you will see when travelling from Central Oregon into the Basin and Range territory. Not nearly as impressive as nearby Winter Ridge, Egli Rim does have a litte more than 1000 feet in relief from valley to crest. Specifically this rim lays on the east side of the Silver Lake Basin.
Poker Jim Ridge: A northern extension of Hart Mountain that is roughly 1500 feet lower in elevation than its southern neighbor. The Poker Jim ridge transitions into the Orejano Plateau, a dry and remote uplift that has segmented off of Poker Jim Ridge and Hart Mountain.
Catlow Rim: The vertical southwestern edge of the Steens Mountain uplift where the Roaring Springs can be found erupting from seemingly indistinct hillside. Near the site of the Roaring Springs, Bighorn Sheep can frequently be seen alongside or crossing the highway as water and feed are abundant here. The four hundred thousand acre Roaring Springs Ranch headquarters located at the base of the Catlow Rim at the Roaring Springs. Much of the Catlow Rim is carved with deep and very steep sided canyons that stretch back into the interior of the Steens.
Guano Rim: Highway 140 from Lakeview to Denio cuts up the side of this 1000 foot tall uplift from the Guano Valley on the Oregon - Nevada border.Notable Basins & Fault PlungesSoutheast Oregon is home to several Great Basin lakes that do not - or no longer - drain to the ocean. Some of the dry basins that do not contain lakes such as the Guano and Catlow Valleys did host large inland seas in the past following the end of the last ice age when increased precipitation and melting ice age glaciers meant more runoff from higher elevations. The drier conditions of the present have left many lakes dry or seasonal only.
Catlow Valley: A large valley southwest of Steens Mountain, one time location of a large Pleistocene lake, now dry other than some small stock ponds and shallow seasonal lakes. Extensive cattle ranching occurs throughout the valley.
Alvord Desert: Alkaline desert east of Steens Mountain. Popular location for drag-racing and windsurfing. Well known hot springs and freshwater lakes such as Mann Lake. The small community of Fields lays at the southern end of this basin.
Warner Valley: West of Hart Mountain, several fresh water lakes including Hart, Crump, and Flagstaff Lakes. The very small ranch town of Plush next to Hart Lake has a small store and gas station, at least as of November of 2007.
Lake Abert: The third largest alkaline lake in North America. The Chewaucan River flowing from a marsh south of Summer Lake drains into Lake Abert which may dry up in extremely arid years. In the past Brine Shrimp were dredged from the lake and sold as "sea monkeys".
Summer Lake: A large alkaline lake located in the basin between Winter Ridge and Diablo Rim. Paisley, with a population of 250 is located alongside the Chewaucan Marsh at the southern end of the Summer Lake Basin. Paisley has at least one gas station and a small store. Summer Lake occupies the salt flats seen below Winter Rim in the picture below.
 Significant Logistical CentersSoutheast Oregon is probably the least civilized area in the pacific northwest, and as such finding gas and food can be difficult. The most significant settlements are Burns and Lakeview.
Located on highway 395 on the northern edge of the Oregon Desert, Burns (population 3000) offers a few lodging and dining establishments. Burns is a good jumping off point for Steens Mountain which lays to the southeast. Further south near Pueblo Peak is the town of Fields which has limited food, gas, and lodging. Burns is 130 miles E-SE of Bend on highway 20.
Lakeview on the border of California is the next largest town with a population of 2500. Mountains near Lakeview include Crane, Drake, and Hart Mountains. Abert Rim can be found approximately 20 miles to the north of Lakeview. For those of you that enjoy roadtrips Lakeview is 216 miles southeast of Bend on highway 31, 140 miles south of Burns along highway 395, or 100 miles east of Klamath Falls on Highway 140.
Resources - Notable Books of Southeast Oregon and External LinksGeologic Field-Trip Guide to Steens Mountain Loop Road, Harney County, Oregon Published by the USGS in 2001.
Hiking Oregon's Geology by Ellen Morris Bishop
In Search of Ancient Oregon by Ellen Morris Bishop
Roadside Geology of Oregon by David D. Alt and Donald W. Hyndman
Hart Mountain Antelope Refuge Homepage
Burns BLM page
WeatherBurns:
Lakeview:
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