Younger Dryas readvance in Squamish river valley, southern Coast mountains, British Columbia

A map of reconstructed Eocene physiography and drainage directions is presented for the southern Interior Plateau region, British Columbia south of 53°N. Eocene landforms are inferred from the distribution and depositional paleoenvironment of Eocene rocks and from crosscutting relationships between regional-scale geomorphology and bedrock geology of known age. Eocene drainage directions are inferred from physiography, relief, and base level elevations of the sub-Eocene unconformity and the documented distribution, provenance, and paleocurrents of early Cenozoic fluvial sediments. The Eocene landscape of the southern Interior Plateau resembled its modern counterpart, with highlands, plains, and deeply incised drainages, except regional drainage was to the north. An anabranching valley system trending west and northwest from Quesnel and Shuswap Highlands, across the Cariboo Plateau to the Fraser River valley, contained north-flowing streams from Eocene to early Quaternary time. Other valleys dating back at least to Middle Eocene time include the North Thompson valley south of Clearwater, Thompson valley from Kamloops to Spences Bridge, the valley containing Nicola Lake, Bridge River valley, and Okanagan Lake valley. During the early Cenozoic, highlands existed where the Coast Mountains are today. Southward drainage along the modern Fraser, Chilcotin, and Thompson River valleys was established after the Late Miocene.

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Glacier fluctuations during the past millennium in Garibaldi Provincial Park, southern Coast Mountains, British Columbia

Canadian Journal of Earth Sciences ◽

10.1139/e07-019 ◽

2007 ◽

Vol 44 (9) ◽

pp. 1215-1233 ◽

Cited By ~ 34

Author(s):

Johannes Koch ◽

John J Clague ◽

Gerald D Osborn

Keyword(s):

British Columbia ◽

Little Ice Age ◽

Ice Age ◽

Southern Coast ◽

Coast Mountains ◽

The Past ◽

Glacier Fluctuations ◽

Garibaldi Provincial Park ◽

Provincial Park ◽

Past Millennium

The Little Ice Age glacier history in Garibaldi Provincial Park (southern Coast Mountains, British Columbia) was reconstructed using geomorphic mapping, radiocarbon ages on fossil wood in glacier forefields, dendrochronology, and lichenometry. The Little Ice Age began in the 11th century. Glaciers reached their first maximum of the past millennium in the 12th century. They were only slightly more extensive than today in the 13th century, but advanced at least twice in the 14th and 15th centuries to near their maximum Little Ice Age positions. Glaciers probably fluctuated around these advanced positions from the 15th century to the beginning of the 18th century. They achieved their greatest extent between A.D. 1690 and 1720. Moraines were deposited at positions beyond present-day ice limits throughout the 19th and early 20th centuries. Glacier fluctuations appear to be synchronous throughout Garibaldi Park. This chronology agrees well with similar records from other mountain ranges and with reconstructed Northern Hemisphere temperature series, indicating global forcing of glacier fluctuations in the past millennium. It also corresponds with sunspot minima, indicating that solar irradiance plays an important role in late Holocene climate change.

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A debris flow triggered by the breaching of a moraine-dammed lake, Klattasine Creek, British Columbia

Canadian Journal of Earth Sciences ◽

10.1139/e85-155 ◽

1985 ◽

Vol 22 (10) ◽

pp. 1492-1502 ◽

Cited By ~ 48

Author(s):

John J. Clague ◽

S. G. Evans ◽

Iain G. Blown

Keyword(s):

British Columbia ◽

Debris Flow ◽

Debris Flows ◽

Southern Coast ◽

Coast Mountains ◽

Debris Avalanches ◽

Unconsolidated Sediment ◽

Sudden Release ◽

Dammed Lake ◽

Unusual Origin

A very large debris flow of unusual origin occurred in the basin of Klattasine Creek (southern Coast Mountains, British Columbia) between June 1971 and September 1973. The flow was triggered by the sudden release of up to 1.7 × 106 m3 of water from a moraine-dammed lake at the head of a tributary of Klattasine Creek. Water escaping from the lake mobilized large quantities of unconsolidated sediment in the valley below and thus produced a debris flow that travelled in one or, more likely, several surges 8 km downvalley on an average gradient of 10° to the mouth of the stream. Here, the flow deposited a sheet of coarse bouldery debris up to about 20 m thick, which temporarily blocked Homathko River. Slumps, slides, and debris avalanches occurred on the walls of the valley both during and in years following the debris flow. Several secondary debris flows of relatively small size have swept down Klattasine Creek in the 12–14 years since Klattasine Lake drained.

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Multi-proxy record of Holocene glacial history of the Spearhead and Fitzsimmons ranges, southern Coast Mountains, British Columbia

Quaternary Science Reviews ◽

10.1016/j.quascirev.2006.09.003 ◽

2007 ◽

Vol 26 (3-4) ◽

pp. 479-493 ◽

Cited By ~ 40

Author(s):

Gerald Osborn ◽

Brian Menounos ◽

Johannes Koch ◽

John J. Clague ◽

Vanessa Vallis

Keyword(s):

British Columbia ◽

Southern Coast ◽

Glacial History ◽

Proxy Record ◽

Coast Mountains ◽

History Of

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Interdecadal patterns of total sediment yield from a montane catchment, southern Coast Mountains, British Columbia, Canada

Geomorphology ◽

10.1016/j.geomorph.2010.01.001 ◽

2010 ◽

Vol 118 (1-2) ◽

pp. 207-212 ◽

Cited By ~ 23

Author(s):

Erik Schiefer ◽

Marwan A. Hassan ◽

Brian Menounos ◽

Channa P. Pelpola ◽

Olav Slaymaker

Keyword(s):

British Columbia ◽

Sediment Yield ◽

Southern Coast ◽

Coast Mountains ◽

Total Sediment

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Early Holocene climate at Castle Peak, southern Coast Mountains, British Columbia, Canada

Palaeogeography Palaeoclimatology Palaeoecology ◽

10.1016/0031-0182(92)90170-a ◽

1992 ◽

Vol 95 (1-2) ◽

pp. 153-167 ◽

Cited By ~ 20

Author(s):

John J. Clague ◽

R.W. Mathewes ◽

W.M. Buhay ◽

T.W.D. Edwards

Keyword(s):

British Columbia ◽

Early Holocene ◽

Southern Coast ◽

Holocene Climate ◽

Coast Mountains

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Pollen evidence of Late Holocene treeline fluctuation from the southern Coast Mountains, British Columbia

Géographie physique et Quaternaire ◽

10.7202/004816ar ◽

2002 ◽

Vol 51 (1) ◽

pp. 81-92 ◽

Cited By ~ 1

Author(s):

Martin Evans

Keyword(s):

British Columbia ◽

Organic Matter Content ◽

Matter Content ◽

Southern Coast ◽

Coast Mountains ◽

Alpine Glacier ◽

The Core ◽

Surface Samples ◽

Summer Temperatures ◽

Glacier Advance

Abstract Palynological records of Holocene climate change in the southern Coast Mountains identify the Neoglacial period, subsequent to 6 600 BP, as cooler and wetter than the preceding Hypsithermal. However, geomorphic evidence of alpine glacier advance suggests that there were three distinct cooler/wetter periods during the Neoglacial. By careful selection of a sensitive alpine site this study has enabled the recognition of two of these stages in a palynological record of Neoglacial climate. Pollen spectra, conifer needle macrofossils, organic matter content, and magnetic susceptibility were assessed for a continuous sequence of sediment from Blowdown Lake, which has a basal date older than 4 000 BP. Comparison of the Picea/Pinus pollen ratios from the core with modern surface samples suggests that treeline was at least 100 m above its present elevation until 3 400 BP, indicating that summer temperatures were at least 0.7 ° C above the present. Treeline declined to near present levels by around 2 400 BP. Two subsequent periods of lower treeline were identified which appear to correlate approximately with the Tiedemann and Late Neoglacial periods of glacier advance in southwestern British Columbia. Differences between Picea/Pinus and Abies/Pinus ratios from the core are consistent with the autecology of the species. This suggests that the sensitivity of the pollen ratio approach to reconstructing treeline is dependent on the ratios selected.

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