Encore - Rainbow Rock

May 30, 2015


 Take a look back at some of the EPODs our viewers found particularly eye-catching. Today and every Saturday, EPOD invites you to rediscover favorites from the past. Saturday posts feature an EPOD that was chosen by viewers like you in our monthly Viewers’ Choice polls. Join us as we look back at these intriguing and captivating images.

Photographer: Randall Scholten; Randy's Web Page
Summary Author: Randall Scholten

Impressive Rainbow Rock is located at the southern end of the Samuel H Boardman State Scenic Corridor, on Oregon’s southern coast. This geological marvel displays radiolarian and diatom compaction in chert and other rock types as well. Radiolarians are amoeba-like protozoa with mineral skeletons that cover large portions of the sea floor. Diatoms are a form of algae encased in a unique form of silica. Both radiolarians and diatoms date back to the Cambrian Period (about 542-488 million years ago). If you look closely, you can see that the rock layers have several small anticlines (upward curved folds) and synclines (downward u-shaped folds). There’s also evidence of faulting within the rock. Faulting likely caused the rock to be exposed as it is today. It’s indeed unusual to have so many different geological features contained in a single rock. Also note the sea stacks just offshore. Photo taken on March 18, 2010.