Esquimalt Lagoon and Barrier Spit EarthCache

1. According to the kiosk information map: Esquimalt Lagoon has what 3 geological items listed on it?
2. According to the kiosk information: How many hectares of eelgrass are growing in the protection of the lagoon?
3. What type of tide was present when you visited the site?
4. Is this a parallel or angle barrier spit? Please explain your answer.
5. Looking at the two CRD photos at the top of the page, notice the hook at the end of the barrier spit. While you are at the posted coordinates look to see if you can see the hook and tell me what you saw, or take and upload a photo of it.
6. Take a picture of your GPSr at the posted coordinates with the channel, the lighthouse or the bridge in the photo.

I hope you have fun doing this earth cache!

2005 (above) Notice the size of the hook at the end of the spit, the tide is out.

2007 (below) Notice the size of the hook in this photo, the tide is in. I love how this photo shows the depth of the barrier spit under water both sides and tidal flats near the channel.

 

The unique geological history and physical processes of Esquimalt Lagoon have created an area rich in wildlife that is highly valued by locals and visitors to the area. This shallow lagoon is enclosed by a sand and gravel barrier spit, and is connected to the ocean with a tidal channel at the northeast end. The lagoon is bordered by some of the oldest Coastal Douglas Fir forest remaining in the Victoria area. The Esquimalt Lagoon is a Migratory Bird Sanctuary. You can park anywhere along the Coburg Peninsula on the seaward side between dawn and dusk.

 

 

What is a Spit?

Spits are one of the many kinds of shore forms found along the coastlines. They are created when wind and water carry enough sand and gravel to create a finger of land. A spit is a strip of beach, which extends into deeper water. Most spits straighten a curving shoreline. Spits often form a straight ridge of sediment across a bay. They commonly develop in the direction of shore drift. A shift in drift direction can form a curve or a hook.

 

 

At one end, spits connect to land, while at the far end they exist in open water. They occur, by the process of longshore drift. Longshore drift, (also called littoral drift) occurs due to waves meeting the beach at an oblique angle, and back-washing perpendicular to the shore, moving sediment down the beach in a zigzag pattern. Simply put, spits occur where the inputs exceed the outputs. As spits grow, the water behind them is sheltered from wind and waves, and a salt marsh is likely to develop.

 

 

Some spits parallel the coast while others extend out from the coast at an angle. Parallel spits are particularly likely to have a salt marsh on its landward side.

 

 

What is a Coastal Lagoon?

A coastal lagoon is a shallow coastal water body separated from the ocean by a barrier, connected at least intermittently to the ocean by one or more restricted inlets.

 

 

 

Tides

Tides change roughly every 6-1/2 hours: The tides ebbs (drops) for about 6-1/2 hours then floods (rises) for about 6-1/2 hours, then repeats the pattern approximately every 24 hours & 80 minutes.

 

 

FTF Congratulations go to D-Tour on July 22, 2010.