A Geology Lesson in Mirabeau Park

Mirabeau Park isn't too far from where I live, and it's a great place to walk and enjoy nature. But I've noticed some white lines in the rocks, some straight, while others were at an approximately 40 degree angle to the straight lines. Below the jump break, there are plenty of pictures plus a link to a very interesting website that covers what happened here many years ago.

These two pictures are from the west side of Mirabeau Park. The rocks look like were pushed up out of the ground, then gravity knocked them over.

We interrupt this program for a photo of a little tree growing out of a rock.

These white lines in the rock are just north of the rocks (pictured above) which have fallen over.

Lines in the side of a small cliff area.

Next, we move around 1500 feet to the south-east. These are white lines in the rocks at the water's edge of the Spokane River, some of the going down under the river's water. 

Lines in the rock face of the artificial waterfall at Mirabeau Springs.

Lines in a rock face along Centennial Trail.

Finding all these white lines in the rocks led me to search out what had happened here geologically. Put simply, it is believed that the crust of the earth was stretched out, and a volcanic dome several counties large pushed the rocks upward until they broke.

A link to a local geology teacher's website is found here. Another very interesting book that I've read which covers this also is named "Washington Rocks". Link here.

It was very enjoyable researching to try to find an explanation of what is written in the rocks.

TLDR: Eastern Washington has had a violent geological past.