If Mountains Could Talk
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If Mountains Could Talk wonders of Garibaldi Park Dr. Bob Turner Bowen Island, Howe Sound [email protected] Retired, Geological Survey of Canada Garibaldi Lake Ranger Station Sept 2014 Black Tusk, May 1986 Standing at the rails, going to Bowen Ferry heading to Bowen Island Bioregionalism: Taking root in my home watershed Garibaldi Bowen Island Garibaldi Geology 6 Big Thoughts Deception Peak from Polemonium Ridge Black Tusk from Panorama Ridge Big Thought #1: The bedrock mosaic Black Tusk Ashlu Range 200,000 year 155,000,000 year old magma (granite) old volcano Panorama Ridge 105,000,000 year old seafloor layers, BigThe ThoughtIce Ages #2: The Ice Age 2 million to 10,000 years ago 2 million to 10,000 years ago cpgeosystems.com You can see the glacier limits Ice Age Glacier Big Thought #3: The Little Ice Age The Ice Age ended 10,000 years ago. But the Little Ice Age just ended 100-200 years ago Warren Glacier about 1800 Big Thought #4: We are in Collision! Garibaldi SW BC is a crustal collision zone (subduction zone) Volcanoes the inevitable consequence Garibaldi of collision (subduction) zones The volcano zone Mount Garibaldi Garibaldi just the top end of a 60-100 km deep plumbing system Volcanic eruption through glacier, Icelend Big Thought #5 erupted during the Ice Age Mamquam Mountain Photo of castle crags, tantalus range Granite peaks! The Chief Big Thought #6: Coast Mountains is granite country map of Garibaldi Lake Sea to Sky Mt country Garibaldi Granite = pink, red, and orange Granite the roots of ancient volcanoes The BC Coast has been producing granite for 180 million years The granite factory Garibaldi 3.5 km 2 km Uplift in 2 km Last 10 million years After Parrish, 1981 The Coast Mountains are rising Bringing granite to the surface! 2 mm/year uplift for 10 million yrs = 20 km Uplift So rocks that form deep in the Earth end up at surface Whistler Cheakamus Lake Access Garibaldi Castle Rubble Creek Access Lake Towers Mt Garibaldi Mamquam Mtn Elphin Lakes Diamond Head Access Squamish Elphin Lakes hike Why such soft ridges amid rugged mountains? And why such rich meadows? Granite Volcanic rock Soft underlying volcanic rocks weather to soft ridges and rich soils. Also, soft sedimentary rock uncommon in the Coast Mountains! 100 million year old seafloor rubble (conglomerate), Elphin Lakes Geological Materials of Garibaldi - viewed in cross section - Volcanic Rocks 1.3 my to 9000 years old Sedimentary Rocks About 100 million years old Garibaldi Lake Hwy 99 Granite 150 to 90 million years old Volcanic Rocks Volcanoes Black Tusk Lava Flows Mt. Garibaldi Ring Creek Sedimentary Rocks Table Barrier Cinder Cone Helm Creek Panorama Ridge Mt Price Gentian Ridge Opal Cone Elphin Lakes Garibaldi Lake Hwy Granite 99 Castle Towers, Guard Mtn, The Sphinx, Mamquam Mtn Geology controls geography Western Garibaldi is a volcanic field: with many volcanoes, lava flows, and eroded volcanic rocks Black Tusk Helm Cr lava flow Cinder Cone Garibaldi Lake Mt Price, Table Barrier lava flow Mt Garibaldi Opal Cone Elphin Lakes Diamond Head parking lot Half the volcano is gone. Original volcano Present location of Elphin Lakes 1 Eruption on Ice Age glacier Present location of Garibaldi Lake 2 Explosive eruptions Mt Garibaldi 3 Collapse as glacier recedes 4Clinker Peak Dalton Dome Opal Cone Cheekeye Ridge Cheekeye Basin How Mt Garibaldi came to be Mayon Diamond Head: remnant of original volcano slope Diamond Head Original volcano slope Diamond Eruption layer Head Eroding Cheekeye Basin Exposes eruption layers that built volcano The view approaching Elphin Lakes Opal Cone Ring Creek valley Trail 9500 years ago Ring Creek lava flow Eruption of Opal Cone and Ring Creek Flow Cinder Ring Creek lava flow Opal Cone crater Cinder Nyamuragira Volcano, ,Democratic Republic of the Congo Opal Cone 9500 years ago Opal Cone Ring Creek lava flow Opal Cone Barrier047_Till.jpg Aerial Post3.jpg Ring Creek lava flow Photo by Paul Adams Opal Cone Lateral ridges form edge of lava flow Ring Creek Lava flow Pressure ridges How ridges form on a lava flow Inflated Cooled lava rock flow Hot lava crust Deflating Collapse Lava collapses; flow stand Ridged Lava Ring Creek lava flow flow Opal Cone Ridges of Trail glacial debris (moraines) The Little Ice Age -1300 AD to 1850 AD Ring Creek Valley New land surface exposed by glacier retreat Opal Cone Old Forests Moraine Trail Garibaldi Lake Trail Rubble Creek trailhead Black Tusk Helm Glacier Panorama Ridge Sphinx Glacier Sentinel Glacier The Table The Barrier The Barrier Hwy 99 1856 Landslide debris Cheakamus River A buried forest Modern forest floor Buried forest floor Mt Price Garibaldi Lake campground Taylor Meadows campground Barrier viewpoint Trail Garibaldi Lake campground Taylor Meadows campground Barrier viewpoint Trail Garibaldi Lake campground Taylor Meadows campground Barrier viewpoint Trail Walking on a lava flow Volcanic rock View of Barrier lava flow from Mt Price Barrier Main flow of lava Secondary lava lobes North of the Lake: Black Tusk, Cinder Cone, Helm Glacier, Panorama Ridge Black Tusk: the eroded remnant of a volcano Black Tusk volcano 200,000 years ago Magma feeder of volcano Glacier Flow direction Trail Trail Castle Towers 1920 View A B From C C Black Helm Glacier Tusk: D Helm E Glacier Panorama Ridge Trail CT 2014 Castle Towers A A C B Helm Glacier C D E Panorama Ridge Trail Helm Glacier 1910s and 1920s GentianGentian Ridge: Ridge A sedimentary rock ridge Folded layers of sandstone(grey) and shale (brown) Helm Glacier Panorama Ridge Trail Sedimentary layers Conglomerate along trail View from Black Tusk: Geology makes the geography Granite peaks Volcanic and Sedimentary Rocks Panorama Ridge viewpoint There is no larger lake at higher elevation in BC Sentinel Glacier Mt Price Clinker Peak Sphinx Glacier Campground Once it was a mountain valley drained by Ring Creek Then Mt Price and later Clinker Peak erupted Lava eruptions block creek Today, Garibaldi Lake: a lava-dammed lake Mt Price Clinker Peak The Table Campground The Table: A very odd mountain Mt Garibaldi The Table Lava layers Lava x x Ancient lava lake View from a plane today Lava lake Glacier surface View from a plane 12,000 years ago Retreat of Sphinx Glacier viewed from Panorama Ridge Koch et al, 2004 Location, Burton Hut Late Ridges in valley from side valley Ridges mark glacier Glacier debris snout position ridge Burton glacier Hut debris 1860s 1928 ridge 1690s Burton Hut and Sphinx Glacier valley If Mountains Could Talk wonders of Garibaldi Park Dr. Bob Turner Bowen Island, Howe Sound [email protected] Retired, Geological Survey of Canada A geological map of Garibaldi area Most of the high ground in western Garibaldi Park volcanic (yellow) or sedimentary (olive). 19121912 Glacier snout near Garibaldi Lake Retreat of Sentinel Glacier 2013 Location, Sentinel Huts (Glaciology Huts) Glacier scratches Sentinel Valley Huts (Glaciology Huts) site under the Sentinel Glacier in 1912 Opal Cone Ring Creek lava flow A view of Garibaldi area Most of the high ground in western Garibaldi Park volcanic (yellow) or sedimentary (olive). A patchwork quilt of different rocks Prince George Calgary Sea to Sky Vancouver Bowen Island .