Sumpter Valley Dredge and John Day Fossil Beds

Tuesday, September 16, 2014

Not far from our campsite and just a short detour from our route was the Sumpter Dredge State Heritage Area, so Tuesday morning we drove up to the site. This part of the Sumpter River Valley had been dredged for gold in the early 20^th century, just as the valley stream in Virginia City, Montana had been. In fact, there are places all over the west where these huge dredges chewed up stream valleys leaving long hills of gravel, and totally blocking and redirecting the streams. This park has an actual restored dredge. Most were stripped and left to rot away in place. Wow! We had no idea how huge these were! No wonder the results were so destructive. It looks like a huge three story white boarded hotel on a barge. The gravel gets scooped up in the front, put on a conveyor belt, transported through the inside, where it gets sifted to smaller and smaller sizes to find the gold, and the leftovers moved up a long conveyor belt high up out the back end, and shot out the back and redeposited into long rows. The dredge is always sitting in water from the rearranged stream, and just floats along within the pond that it makes for itself.
 

The Sumpter Gold Dredge

Electric motors powered everything - winches, pumps, belts, chains 

Tail end dump conveyor covered for preservation

Of course no one did remediation, or stream restoration then, so 100 years later, the mess still remains. Slowly the vegetation, birds, and animals have been reclaiming it, but it can never be restored to its original configuration. Sad what we did to these beautiful stream valleys in our thirst for gold.


The day was heating up and we continued on to the fossil beds. After stops in the town of John Day for fuel and groceries, we realized that the day was getting long, and we wouldn't have time to hike once we got there. Besides, it was sunny and in the 90's! We made the decision to go to the visitor center, get oriented and put off the hikes until early the next morning. The monument is in three non-contiguous units. We decided to visit the two closest ones.


The visit to the L Thomas Condon Paleontology Center with its great exhibits of the fossils, geology, and history of the area was very well done. We spent a long time there getting a handle on the fossil record which runs from 50 million years ago to 5 million years ago, essentially newer than the dinosaurs, it documents the Age of Mammals. My one disappointment was that in the two units we chose to visit there were no fossils to be seen along the trails. Fossil digging is punishable, and they are vague about where fossils have been found. The only legal place to dig is behind the high school in the town of Fossil. Unfortunately, we weren't going that direction. Greg isn't as interested in paleontology as in the geologic structure, so he had to drag me out of the center when he got bored. I love fossils! The idea of seeing something that was alive those many million years ago is thrilling!

Volcanic ash deposits of the John Day Fossil Beds - Sheep Rock Unit

Beautifully preserved Sycamore leaves from 44 million years ago

Palm leaf

Ancestral Easter Bunny!

Early elephant jaw

Fossilized egg

Greg's Commentary – The John Day Fossil Beds consist mostly of horizontal or gently dipping beds of volcanic ash with a few layers of lava and ignimbrite (glowing hot ash and cinders that welded into a hard rock) that erupted and fell over the landscape of forests and grasslands at intervals of several thousand years during a span of 50 million years. Between ashfalls of a few to dozens of feet thick, soils formed that supported a wide variety of plants and animals, including some of the more charismatic mamalian megafauna like mammoths, sabertooth cats, and ancestral bears, wolves, horses, and many others. New ashfalls would kill many animals and preserve both animal and plant fossils on the previous soil surface. These well preserved and relatively easily excavated fossils were very influential to the understanding of geology and evolution during the early days of the science beginning about 1850. Later investigation using more detailed and advanced methods, such as radiometric dating, microfossil analysis (pollen, spores, etc.) yielded a better understanding of entire ecosystems.

Looking south at Picture Gorge below Sheep Mountain

We still needed a place for the night, so we drove north through the park along the John Day River until we reached the North Fork of the John Day. Finding a very small BLM campground, Big Bend, along the river banks we paid our $2.50 and settled in to the sounds of the river and waited for the sun to set and cool things down.

Our camp along the North Fork of the John Day