Flexibility Renewal Master Version 3_19_15_4
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Flexibility Renewal Master Version 3_19_15_4
Portland state UniversityPDXScholarDissertations and ThesesDissertations and Theses1987Geomorphic character, age and distribution of rock glaciers in Flexibility Renewal Master Version 3_19_15_4 the Olympic Mountains, WashingtonSteven Paul WelterPortland State UniversityFollow this and additional works at: https://pdxscholar.library.pdx.edu/open_access_etds& Part of the Geology Commons, and the Geomorphology CommonsLet us know how access to this document benefits you.Recommended CitationWe Flexibility Renewal Master Version 3_19_15_4lter, Steven Paul, 'Geomorphic character, age and distribution of rock glaciers in the Olympic Mountains, Washington" (1987). Dissertations and ThesesFlexibility Renewal Master Version 3_19_15_4
. Paper 3558.https://doi.org/10.15760/etd.5440This Thesis IS brought to you for free and open access. It has been accepted for inclusion in DissertatiPortland state UniversityPDXScholarDissertations and ThesesDissertations and Theses1987Geomorphic character, age and distribution of rock glaciers in Flexibility Renewal Master Version 3_19_15_4TRACT OF THE THESIS OF Steven Paul Welter for the Master of Science in Geography presented August 7, 1987.Title:The Geomorphic Character,Age, and Distribution of Rock Glaciersin the Olympic Mountains, WashingtonAPPROVED BY MEMBERS OF THE THESIS COMMITTEE:Rock glaciers are tongue-shaped or lobate mas Flexibility Renewal Master Version 3_19_15_4ses of rock debris which occur below cliffs and talus in many alpine regions. They are best developed in continental alpine climates where it is coldFlexibility Renewal Master Version 3_19_15_4
enough to preserve a core or matrix of ice within the rock mass but insufficiently snowy to produce true glaciers. Previous reports have identified anPortland state UniversityPDXScholarDissertations and ThesesDissertations and Theses1987Geomorphic character, age and distribution of rock glaciers in Flexibility Renewal Master Version 3_19_15_4 has been made regarding the geomorphic character, age,2 and distribution of these features.The purpose of this study is two-fold. First, surface sediment fabric analysis and relative and absolute dating methods are used to determine the geomorphic character and age of Akela rock glacier. Secondly, Flexibility Renewal Master Version 3_19_15_4the distribution of rock glaciers in the northeast Olympics is analyzed in terms of topoclimatic and geologic factors in order to understand the envirFlexibility Renewal Master Version 3_19_15_4
onmental conditions under which they formed. In addition, the distribution of rock glaciers is compared to that of past and present glaciers.RadiocarbPortland state UniversityPDXScholarDissertations and ThesesDissertations and Theses1987Geomorphic character, age and distribution of rock glaciers in Flexibility Renewal Master Version 3_19_15_4y not been active for at least 200 to 300 years. Relative age data indicate that the surface of the rock glacier is variably-aged; boulders at the head of the rock glacier have been most recently deposited and have been least influenced by rock glacier flow. In contrast, boulders at the rock glacier Flexibility Renewal Master Version 3_19_15_4 toe display signs of being inactive for many years. Boulders at the rock glacier toe and upper lobe face display a preferred orientation, which is atFlexibility Renewal Master Version 3_19_15_4
tributed to past rock glacier activity. The lateral ridges of the rock glacier were the first areas to stabilize, probably more than 1000 years ago. IPortland state UniversityPDXScholarDissertations and ThesesDissertations and Theses1987Geomorphic character, age and distribution of rock glaciers in Flexibility Renewal Master Version 3_19_15_4tive. These results indicate that both fabric analysis and relative dating methods can be used to better understand the geomorphic character and age of rock glaciers.Rock glaciers in the Olympic Mountains occur entirely within the3 more continental northeastern section of the Olympics. Within this a Flexibility Renewal Master Version 3_19_15_4rea, they are preferentially located to the lee of the Needles Ridge and Mt. Constance Massif, where precipitation is most limited. These rock glacierFlexibility Renewal Master Version 3_19_15_4
s may be composed of either sandstones or basalts, but are restricted to areas where their debris supply is coarse and blocky .The surface character oPortland state UniversityPDXScholarDissertations and ThesesDissertations and Theses1987Geomorphic character, age and distribution of rock glaciers in Flexibility Renewal Master Version 3_19_15_4t or past glaciers as a result of their formation in areas of limited snow accumulation. Also, their downslope elevation may be restrained by lack of debris from the cliffs above them. The mean rock glacier toe elevation of about 1700 m suggests an approximate lower limit for discontinuous Neoglacia Flexibility Renewal Master Version 3_19_15_4l permafrost.GEOMORPHIC CHARACTER, AGE AND DISTRIBUTION OF ROCK GLACIERSIN THE OLYMPIC MOUNTAINS, WASHINGTONbySTEVEN PAUL WELTERA thesis submitted inFlexibility Renewal Master Version 3_19_15_4
partial fulfillment of the requirements for the degree ofPortland state UniversityPDXScholarDissertations and ThesesDissertations and Theses1987Geomorphic character, age and distribution of rock glaciers in Portland state UniversityPDXScholarDissertations and ThesesDissertations and Theses1987Geomorphic character, age and distribution of rock glaciers inGọi ngay
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