GSA GeoVenture 2008

Geology of the Middle Fork of the Salmon River, Idaho

29 August – 4 September 2008
6 day river trip from Indian Creek to Cache Bar

Trip Overview

This 7 day trip is a fully outfitted expedition on the Middle Fork of the Salmon River traveling through Impassable Canyon in the largest wilderness in the lower 48 states. The Middle Fork is considered a class IV river and offers a great opportunity to experience the thrill of river rafting while learning about the geology of this secluded region. The trip will focus on the geomorphology and hydrology of the Middle Fork of the Salmon River as they relate to historical and current geologic events. A brief overview of the long-term geologic history and bedrock geology of the region will provide a contextual background for the trip. Topics such as glacial, incision, and landslide history, fluvial deposition, terrace formation, sedimentation, and bedrock composition will be covered at one to two study sites each day that will provide participants an opportunity for discussion and interpretation of the landscape.

DAILY ITINERARY

Aug 29, Fri

• Fly into Boise, ID Airport (code BOI) and arrive before 2:00pm. Our van shuttle from the Boise Airport to Stanley, ID (2.5hr drive) will leave at 2:45pm sharp. Shuttle pick-up will be at the airport. (More info to come on exact meeting place at airport.)
• Trip orientation at the Mountain Village Lodge in Stanley, ID at 6:00pm in the conference room. Presentation on the regional geologic history and bedrock geology of the region. Overnight at the Mountain Village Lodge is included in the registration fee.

Day One - Aug 30, Sat

• 8:00 AM: Meet in lobby of the Mountain Village Lodge. Chartered flight into the “put-in,” location at Indian Creek (flight included in reg fee). Forest Service wilderness orientation, river safety orientation, and day one Geology orientation.
• Study Site #1: Hike to the top of the Indian Creek terraces. Discussion of the geologic history of the canyon, glacial history and the subsequent deposition of river “fill” terraces
• Study Site #2: Exploration of the Pungo Creek fluorspar and discussion of the bedrock geology in Pungo Canyon.
• Study Site #3: Discussion, study, and interpretation of the Orelano Creek landslide and associated fluvial deposits.
• Camp Hike – TBD
• Camp One – Fireside Discussion: Recap of the geology of the day and fireside discussion

Day Two – Aug 31, Sun

• Morning Presentation: The response of fluvial systems to wildfire with specific reference to the 2000 and 2007 fire season.
• Study Site #1: Observation of Caston Pluton Granites. Discussion of how these granites relate to the regional geologic history.
• Study Site #2: Discussion, study, and interpretation of the Jack Creek landslide and alluvial fan. Stop at various sites burned in 2007 and study the geomorphic response to the event.
• Camp Hike – TBD
• Camp Two – Fireside Discussion: Changes in bedrock geology and control on fluvial erosion

Day Three – Sept 1, Mon

• Morning Presentation: Glacial history and terrace formation, dating techniques of fluvial terraces, discussion of historical glacial cycles.
• Study Site #1 – Whitey Cox gravel bar evolution. Discussion of the factors that relate to the movement and sedimentation of river born sediment.
• Study Site #2: Terraces observation along the river.
• Camp Three – Field Hike: Walk to Loon Creek hot springs. Talk about ground water hydrology. Tour the bedrock granite gorge up Loon Creek canyon.
• Camp Four – Fireside Discussion: Recap of the day, further discussion of terraces and their relation to fluvial systems.

Day Four - Sept 2, Tues

• Morning Presentation: Bedrock geology and controls on river incision. Tappan Canyon Metamorphics. Alluvial fan development into river systems and how they relate to fluvial terraces. Day four geologic overview.
• Study Site #1: Grouse Creek – observation and discussion of alluvial fan evolution and its effects on channel migration.
• Study Site #2: Tappan Canyon Overlook – observation and discussion of bedrock controls on river incision
• Study Site #3: Haystack Rapid (Pole creek and Bernard creek) landslides. Observation and discussion of long-term alluvial fan history.
• Camp Four – Field Hike: Observation and discussion of the changing bedrock geology along the river. Sedimentary and Metamorphic rocks and how they may relate to the geologic history of the region
• Camp Four – Fireside Presentation: Discussion of catastrophic landslide events and their effects on the river system and fluvial deposition.

Day Five – Sept 3, Wed

• Morning Presentation: Background on the bedrock geology of the river and how it relates to the geologic history of the region. Day five geologic overview.
• Study Site #1: Sheep licks – detailed discussion of catastrophic landslide dam sedimentation.
• Study Site #2: Cutthroat Cove Rapid or Weber Rapid – Observation and interpretation of catastrophic landslide dam sediments.
• Study Site # 3: Papoose Creek – observation of bedrock geology of the river canyon and how it relates to geologic history. Discussion of metamorphic rocks.
• Camp Five – Filed Hike: Climb the canyon walls to observe the depth of the Impassable Canyon.
• Camp Five – Fireside Discussion: Fluvial terrace history and historical rates of incision in the Impassable Canyon. Trip Recap

Day Six – Sept 4, Thu

• Morning Discussion: Brief overview of the day, discussion of varying degrees of metamorphism.
• Study Site #1: Gravel Bar, observe and appreciate the beautiful river rock created by the canyon.
• Study Site #2 – Cramer Creek Rapid – landslide rapid evolution.
• Take-Out – Take out at Cache Bar, lunch and load up in the vans, drive back to Boise, ID. Arrive in Boise about 8:00pm. End of Tour.

The river company will have a vehicle going back to Stanley, and GSA has arranged for van transportation back to Boise, which is a 7.5 hr drive from the take-out. The van will make a drop off at the Best Western Vista Inn near the airport around 8:00pm. GSA has reserved a block of rooms at a discounted rate at this new hotel near the airport, but you will need to call to make your own reservation by Fri, Aug 22. Ask for the room block under GSA GeoVentures. The hotel will release the extra rooms after the 22nd. This last night is not included in the registration fee and individuals will need to arrange payment. A last shuttle stop will be to the airport around 8:15pm.

After the trip, if you wish to fly from Salmon, ID to Boise ID instead of riding the van, you can book a flight with Arnold Aviation, 1-877-382-3941. A one-way ticket from Salmon to Boise is US$190. (PLEASE BOOK EARLY.)

For those of you who wish to drive to Stanley, you will need to be there on Fri, Aug 29, at 5:30pm as the required orientation will start at 6:00pm sharp at the Mountain Village Lodge. If you plan to be late, please call Adventure Guides to let them know. Also please call the Mountain Village Lodge to inquire about leaving your vehicle during the trip. You will be able to take the river company shuttle back to Stanley and the Mountain Village Lodge at the end of the tour.

Contact Information:

Adventure Guides river company 1-888-948-4337 [ www.riveradventureguides.com ]

Wesley Hill, GSA GeoVentures 303-357-1005

Mountain Village Lodge, Stanley 208-774-3661

Van Shuttle 1-800-831-8942

Best Western Vista Inn, 208-336-8100

Included in the Tour Registration Fee:

• Van transfer from Boise, ID Airport to Stanley, ID.
• First night hotel stay at Mountain Village Lodge in Stanley, ID
• Crew of professional guides that row the boats, set up camp, and do all of the cooking.
• All sleeping gear and tents
• Water proof bags to pack personal items
• All meals and beverages
• Van transfer from river take out point to Boise, ID
• Guidebook/Field Notes

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