Scimitar Glacier originates below the northeast face of Mt. Waddington in the southern British Columbia Coast Mountains and flows 18 km down valley to calve into a proglacial lake. The purpose of this research was to describe the late Holocene glacier history of Scimitar Glacier using stratigraphic analysis in conjunction with dendroglaciologic and radiocarbon dating techniques. Downwasting of the glacier surface has exposed stacked till units separated by wood-bearing horizons in the proximal slopes of lateral moraines flanking the glacier at several locations. Historical moraine collapse and erosional breaching has also revealed the remains of standing trees buried in sediments from a lake originally ponded against the distal moraine slope. Radiocarbon dating of detrital wood remains revealed that Scimitar Glacier expanded down-valley at least three times in the late Holocene. The earliest period of expansion occurred 3167-2737 cal yr BP in association with the regional Tiedemann Advance. Following this the glacier receded and downwasted prior to advancing to reconstruct the lateral moraine in 1568-1412 cal yr BP during the First Millennial Advance. The most recent phase of moraine construction was initiated during late Little Ice Age glacial expansion before 1742 AD and extended until at least 1851 AD, after which Scimitar Glacier began to recede and downwaste. Field investigations at Scimitar Glacier allowed for the construction of a late Holocene history of glacier expansion and lateral moraine construction that spans the last 3000 years. This record is comparable to that recorded at other glaciers in this region, and confirms the long-term relationship between regional climate trends and glacier behaviour in this setting. / Graduate

This thesis attempts to unravel the complex thermal and structural history of part of the High Himalayan Slab in NW India and combines reconnaissance-style field structural mapping of an area covering ~10,000 km² with petrography, microstructural analysis, thermobarometry and geochronology techniques. The results of this work show that the oldest protoliths of the High Himalayan Slab are at least Cambrian in age and that they may have experienced a major pre-Himalayan metamorphism at c.500 Ma. The youngest protoliths are Mesozoic in age (the Tandi Group) and demonstrate that the High Himalayan Slab represents the metamorphosed equivalents of the Tibetan Sedimentary Series. Metamorphism was achieved via substantial crustal shortening and thickening following the India-Asia collision at 50-54 Ma ago. Phase relationships demonstrate that metamorphism was a regional Barrovian-type event associated with the growth of biotite-, garnet-, staurolite-, kyanite- and sillimanite-bearing assemblages in metapelites. Quantitative thermobarometry demonstrates that near-peak conditions of c.6-8 kbar and 550-650°C were attained in the deepest exposed levels. Growth of metamorphic assemblages was underway by at least 30 Ma, as indicated by U-Pb ages of metamorphic monazites. Exhumation of the High Himalayan Slab was achieved through a combination of extensional unroofing along major detachments (namely the Zanskar Shear Zone), thermal doming, thrusting along the Main Central Thrust and surface erosion. Exhumation is closely associated with the growth of sillimanite- and cordierite-bearing assemblages in pelites and the generation and emplacement of crustal melt leucogranites in the upper parts of the slab. U-Pb dating of accessory phases from one of the crustal melt leucogranites (the Gumburanjon leucogranite) constrains its crystallisation and emplacement age at c.21-22 Ma. This is only slightly older than its ⁴⁰Ar/³⁹Ar muscovite and biotite cooling ages of c.20-21 Ma, which is attributed to the emplacement of the Gumburanjon leucogranite into the immediate footwall of the ZSZ. Field and geochronological data therefore support a strong temporal and spatial relationship between upper crustal melting and extension in a convergent orogen.

No description available.

No description available.

Thesis (M.S.)--Baylor University, 2007. / Includes bibliographical references (p. 87-95).

Thesis (M.S.)--Baylor University, 2007. / Includes bibliographical references (p. 128-136).

Thesis (Ph. D.)--University of Western Sydney, 2003. / A thesis submitted in fulfillment of the requirements for the degree of Doctor of Philosophy at the University of Western Sydney, School of Humanities, 2003. Includes bibliographical references.

Thesis (D.Phil.(Geography))-University of Pretoria, 2007. / Includes summary. Includes bibliographic references (leaves 185-188).

Thesis (M. Sc.) (Hons) -- University of Western Sydney, 2005. / "A thesis submitted in part fulfilment of the requirements for the degree of Master of Science (Hons.) at University of Western Sydney" Bibliography : leaves 207 - 221.

Thesis (Ph. D.)--University of Tennessee, Knoxville, 2007. / Title from title page screen (viewed on June 10, 2008). Thesis advisor: Henri D. Grissino-Mayer. Vita. Includes bibliographical references.