Dawning of a Dune EarthCache

Located at Deception Pass State Park's Sand Dunes Interpretive Trail. The trail is a paved/gravel 1.2 mile loop with minimal elevation change. Due to the fragile nature of the plants in the area , please stay on the paved or designated gravel. In order to answer all the questions one must complete the entire loop trail path.

There is a $10 day-use fee or $30 annual pass charged to use all Washington State Parks.



Along the inland Salish Sea, sand dunes are a unique geological feature. Bordering the Strait of Juan de Fuca, the conditions here are similar to open oceanfront.

Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. The composition of sand is highly variable, depending on the local rock sources and conditions.

Sand Dune Formation:
A sand dune needs the following three things to form:

1.) A large amount of loose sand in an area with little vegetation, usually on the coast or in a dried-up river, lake or sea bed.
2.) A wind or breeze to move the grains of sand.
3.) An obstacle that causes the sand to lose momentum and settle. This obstacle could be as small as a rock or as big as a tree.
Where these three variables merge, a sand dune forms. As the wind picks up the sand, the sand travels, but generally only about an inch or two above the ground. Wind moves sand in one of three ways:
1.) Saltation: The sand grains bounce along in the wind. About 95 percent of sand grains move in this manner.
2.) Creep: When sand grains collide with other grains like clay or gravel causing them to move. Creep accounts for about 4 percent of sand movement.
3.) Suspension: Sand grains blow high in the air and then settle. About 1 percent of sand moves this way.

Once it's in motion, sand will continue to move until an obstacle causes it to stop. The heaviest grains settle against the obstacle, and a small ridge or bump forms. Because the obstacle breaks the force of the wind, the lighter grains deposit themselves on the other side of the obstacle. Eventually, the surface facing the wind crests, and the lighter grains of sand cascade down the other side, or the slip face. This is how a sand dune may actually move over time -- it rolls along, maintaining its shape as it goes.

To qualify as a "find", email, (do not post online), the answers to the following questions. Please e-mail us at the same time you log your find. Failure to do that in a timely manner will result in a log deletion.

Please visit the interpretive signs along the trail and answer the following questions:

1) How many ecosystems are detailed along this trail and what are their names? (The number can be found on the sign at the coordinates but you will have to walk the trail to find their names!)

2) What evidence is there of this area's salty past?

3) What element of sand dune formation is the most obvious here?

4) Now that you have completed the loop, what do you think caused these dunes to be formed at their current location?

If possible please post a picture of you or your GPSr with some sand dunes/and or the beach at the park. (Who doesn't bring a camera to this gorgeous park!) We hope you have learned a thing or two about sand dunes and thanks for visiting the Deception Pass State Park.

Warning: Earthcaches come with a unique set of rules and activities that must be met before successfully logging. Failure to comply will result in a log deletion.