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Rock Quarries and Gravel Pits Field Trip

Tour with Bill Montgomery, CEMEX Executive, and GSOC Past Presidents Bo Nonn and Larry Purchase

Join us for a one day field trip to study Missoula Floods gravel and cobble deposits, plus Boring volcanism in Clark County on Saturday, June 17, 2017.

Trip Participation Policies

If you plan on participating in this trip, please register below by June 10, 2017. All participants must be GSOC members or their guests. Limited to the first 25 participants.


Fee of $30.00 includes field trip guide, insurance and speaker honoraria. All other costs and arrangements are the responsibility of the participants, including transportation and lunch. Larry will assist facilitating the car pool arrangements, so participants should indicate needs or offers to accept passenger(s). Cars can be left at the meeting place, to be determined, as only 5 or 6 vehicles can safely negotiate the quarry & gravel pits, in convoy.


We will meet at a place to be confirmed, near the Fisher Hard Rock Quarry on the Columbia River. Proceed to Lacamas Lake, & Home Depot Gravel Pit Complex. Go north to the Battle Ground Lake City Park for lunch. We will then proceed west, passing by a ditch built by the Chinese, to the Lewisville Gravel Pit, back south to the Orchard Gravel Pit, and from there to our parked cars .

Things to Do If You Plan on Participating

  1. Register by Saturday, June 10, 2017.
  2. Join GSOC if you are not a member.
  3. Make car pool arrangements.
  4. Bring rock hammer, safety glasses, etc. (I will have a 4 pound hammer for use.)
  5. Wear or bring appropriate clothing.
  6. Bring water bottle, hat, sunscreen, sunglasses, hand lens (loop), and binoculars.
  7. Meet at place to be confirmed. Place & directions will be on GSOC web page here.

Rock Quarries and Gravel Pits Field Trip
from 30.00

One day field trip to study Missoula Floods gravel and cobble deposits, and Boring volcanism in Clark County on Saturday, June 17, 2017.

Detailed Itinerary

  1. Fishers' Hard Rock Quarry - operational - 192nd & SR 14. Note – Floods sheared off south side of Prune Hill looking east. 20 million tons of rock has been mined out since 1884. Most of the rock used in the north & south jetties at the mouth of the Columbia River were extracted shortly after 1900. We will visit this hard rock Quarry.
  2. Washougal Gravel Pit - Evergreen Hwy & SE 356 St. - Agates found due to gravel being from the Troutdale Formation. Pit may or may not be available for us to visit due to overburden being removed.
  3. Lacamas Lake (Kolk) – SR 500 & NW Lake Rd. - Flood was about 400 feet overhead. A Kolk is an extremely strong vortex that swirls around a more or less vertical axis in deep water that is flowing very fast. Kolks are capable of plucking boulders out of solid bedrock & leaving depressions. The depressions fills with water. We may make a lunch stop here where bathrooms are available.
  4. Home Depot Gravel Pit Complex - 192nd & Mill Plain Rd. – A south pit “Columbia Technical Center” (CTC), has Home Depot, Walmart, & a host of other businesses built in the vacated 80 foot deep, pit depression, over a mile long. 30 million tons of gravel was removed for this business development. Ironically, 520 feet of gravel still remain below the development, but will never be removed. The middle adjacent pit to the north “English Pit”, & another northern adjacent pit to that, “Firstenburg Pit” are both operational, & will be visited by us.
  5. Orchard Gravel Pit – SR 503 & 500. - Operational part on the west side has an asphalt & cement plants hidden below grade, which we will visit. Garbage has been deposited in the pit on the east side, & has a single family housing tract built over it. We may drive by for a look.
  6. Battle Ground Lake (Maar) – NE 182nd Av. & NE 249th St. - Missoula Floods did reach the lake at 550 foot elevation, which is a Boring Volcanic, Maar. A Marr is a crater caused by an explosion of gas or steam which occurs when groundwater comes into contact with hot lava. Bathrooms are available.
  7. Lewisville Gravel Pit - operational - N E Park Drive & 112th Av. Gravel on this terrace above the river, is thought to be in the Troutdale Formation, & is in the East Fork Lewis River, Missoula Flood Channel. (Reference Rick Thompson)
  8. Canby Gravel Pit - operational - just to the southwest & on the other side of the Mollala River from the "Canby Delta Gravel Bar." (Optional, not on trip due to travel distance.)