Stone stripe

  (Redirected from Lava stringer)

A stone stripe, also called a lava stringer,[1] is an elongated concentration of mostly talus-like basalt rock found along a hillside or the base of a cliff. Many stringers occur without cliffs. A stringer is identified by its lack of vegetative cover. They typically occur in north central Oregon and develop at 900 to 1,100 meter elevations. Lengths can range from only a few meters to over 150 meters, and widths measure from .3 to 3 meters. Depths of the stringers range from 20-65 centimeters.[2]

Stone stripes on Catlow Rim in Oregon

FormationEdit

Stone stripes are thought to have been originally created by periglacial conditions of the Quaternary period during an Ice age. It is likely their formation originates from multiple processes including frost action, surface erosion, eluviation, and mass wasting. However, it is likely that intense freeze and thaw cycles account for the natural sorting of the rock debris within a stone stripe, and also accounts for the shallow depth of the stripes, since frost penetration is thought to not penetrate deeper than 1 meter in the region.[3]

Stone stripes are also found surrounding soil mounds of central Oregon which also owe their formation to freeze and thaw cycles. They are called stone rings and form on more level terrain. As the terrain increases in slope, stone rings transition into stone stripes.[4]

GalleryEdit

See alsoEdit

External linksEdit

Mystery of the Desert Mounds

ReferencesEdit

  1. ^ Maser, Chris; Geist, J. Michael; Concannon, Diane M.; Anderson, Ralph; Lovell, Burrell (1979). Wildlife Habitats in Managed Rangelands-- The Great Basin of Southeastern Oregon: Geomorphic and Edaphic Habitats. U.S. Department of Agriculture. pp. 11–12. Retrieved 2016-12-01.
  2. ^ Pyrch, John Baine (1973). The Characteristics and Genesis of Stone Stripes in North Central Oregon. Portland State University. pp. 1–2. Retrieved 2020-08-01.
  3. ^ Pyrch, John Baine (1973). The Characteristics and Genesis of Stone Stripes in North Central Oregon. Portland State University. pp. 111–121. Retrieved 2020-08-01.
  4. ^ Nelson, Clark A. (1977). The Origin and Characteristics of Soil Mounds and Patterned Ground in North Central Oregon (PDF). pp. 15–16. Retrieved 2020-08-04.