2013-09-14 Jim Aldrich: Development of Olympic Mountains

About the Field Trip: Structural Development of the Olympic Mountains

2013 – Sept. 14-15

Read/download field guide – 16 pages…

Read/download color photo summary of the field guide…

Jim Aldrich, who has been working on a geologic investigation of the structure geology and tectonics of the mountains for three years, was the trip leader.

Original announcement: The trip will originate and end at the Olympic National Park visitor center on the south side of Port Angeles. The trip starts at 9:00 am Saturday, September 14. The first day we will be stopping at outcrops of the Olympic Subduction Complex (OSC) Lower unit on the Pacific Coast and the oldest strata of the Coast Range Terrane on the north flank of the mountains. We will stay at a motel in Port Angeles that night. The second day we will be examining outcrops of the OSC Upper unit in the core of the range and the upper strata of the Coast Range Terrane along Hurricane Ridge Road. The longest walks to outcrops are two that are about 1/4 mile down a moderate grade. All other stops are at outcrops across a road. The field trip will end by 5 pm September 15th. Costs: There is no trip fee. Participants will have to pay for their own motel room, or the cost to share a room if they are willing to do that, and meals.

This field trip includes stops to observe and hear about the geology of the three major rock sequences of the Olympic Mountains – from the Pacific Coast to the core rocks on Hurricane Ridge.

Read more about Jim Aldrich, the leader…


Discussion of Hurricane Ridge fault where it cross Hurricane Ridge Trail. Field trip participants gather around to get closer look at Beach 4 primary sedimentary structures

Read archived announcement of this field trip…

Jim discussing turbidite deposits and deformation at Beach 4
Jim discussing turbidite deposits and deformation at Beach 4
Jim discusses the nature of deformation in eastern Olympic Mountains accretionary complex.
Jim discusses the nature of deformation in eastern Olympic Mountains accretionary complex.