- published: 21 Jul 2015
- views: 17299
A rock shelter (also known as a rockhouse, crepuscular cave, or abri) is a shallow cave-like opening at the base of a bluff or cliff.
Rock shelters form because a rock stratum such as sandstone that is resistant to erosion and weathering has formed a cliff or bluff, but a softer stratum, more subject to erosion and weathering, lies just below the resistant stratum, and thus undercuts the cliff.
Many rock shelters are found under waterfalls.
Rock shelters are often important archaeologically. Because rock shelters form natural shelters from the weather, prehistoric humans often used them as living-places, and left behind debris, tools, and other artifacts. In mountainous areas the shelters can also be important for mountaineers. In western Connecticut and eastern New York, many rock shelters are known by the colloquialism "leatherman caves", as they were inhabited by the Leatherman over three decades in the late 19th century.
In arid areas, wind erosion (eolian erosion) can be an important factor in rockhouse formation. In most humid areas, the most important factor in rockhouse formation is frost spalling, where the softer, more porous rock underneath is pushed off, tiny pieces at a time, by frost expansion from water frozen in the pores. Erosion from moving water is seldom a significant factor.
Jenha MBOBINE "ABRI"
Try Sutrisno Panglima ABRI yang di Segani oleh Falintil dan Fretilin ( Operasi Seroja )
ABRI - Sejak SD (Official Video)
Mars ABRI
Jacques, 50 ans, est un sans abri parisien, sa passion le bodybuilding, sa salle de sports la rue
ABRI - A Piece of Yourself
Bricoler avec Roger - Construire un abri de jardin
SCRAP MECHANIC : 3 maisons au TOP & Abri 101 (Fallout)
Toser One Ft. Hopper & None - Abri La Puerta De Mi Casa | Video Oficial | HD
Fabrication d'un abri naturel - abri en appentis !
ABRI - Menangis Sambil Malu (Official Lyric Video)
Elles sont des dizaines de milliers sans abri - INFRAROUGE
Georgio - A l'abri (EP "A l'abri" DISPONIBLE PARTOUT!)
Abri, sluta jämföra oss (DEL 1)