HISTORICAL GEOLOGY FIELD TRIP: JOHN DAY FOSSIL BEDS. June 5 & 6, 2009

This two day trip will explore the vibrant colored, fossil-rich rocks of the John Day Basin. These formations represent 48 million years worth of sedimentary accumulation during a time when Eastern Oregon’s climate was lush and forested, full of deciduous trees and lakes. The majority of fossil-bearing rocks are either on private land or within the boundaries of the John Day Fossil Beds National Monument. The Monument is divided into 3 main parks, or ‘units’: The Clarno Unit, the Painted Hills Unit and the Sheep Rock Unit. (See the map below)

The majority of rock formations in the monument are sedimentary. The major fossil-bearing formations, from oldest to most recent, are the Clarno Group, John Day Group, Mascall Formation and the Rattlesnake Group (See the table below). Volcanic rocks are layered in some places between sedimentary formations.

Fossil bearing formations:	Age	Abbreviated List of Fossils Found
Clarno Group	54 to 37 million yrs. ago	Alligators, crocodiles, turtles, nimravids, 3-toed horses, rhinoceros, pines,palms, dogwoods, roses
John Day Group	39 to 18 million yrs. ago	Snakes, Opossum, Nimravids, 3-toed horses, bears, canines, rhinoceros, camels, beavers, ferns, conifers, pines, dogwoods, walnuts, roses
Mascall Fm.	15 to 12 million yrs. ago	Turtles, Falcons, 3-toed horses, bears, canines, rhinoceros, camels, beavers, gingko, conifers, pines, lilies, dogwoods, walnuts, roses
Rattlesnake Group	8 to 6 million yrs. ago	Frogs, turtles, 3-toed horses, canines, rhinoceros, camels, beavers, roses

LOGISTICS:

Ø WE will meet in the north parking lot of CBC at 6:45. We will leave at 7:15 sharp. Do not be late; we WILL leave you behind!

Ø We will explore each unit of the Monument, including a tour of the Thomas Condon Paleontology Center. We will also collect fossils in both Tertiary & Mesozoic sediments. Bring a rock hammer, plastic baggies to store your fossil, a cold chisel set and a prybar. Bring a sharpie marker to label your samples. Wear appropriate attire- we will get FILTHY! It may rain, and then we are collecting in mud!

Ø Our overnight stay will be at a campground nearby. You will need a tent, a sleeping bag good for temperatures down to the upper 30’s, and cooking gear. Meals are not supplied, but a cooler will be, to store your perishables.

Ø The group will break for camp around 4 pm. At that time, you can choose to relax around the campfire, take additional hikes, or go fishing. World-class fishing in the John Day River is nearby.

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