The Ocean/Sea has always fascinated me although I’ve not had the opportunity to spend much time near it. This Earth cache is an exploration into what an estuary is. The earth cache will be to take a look at several different aspects within the estuary itself that you can observe here at this location. Basically an estuary is a transition zone between land and sea where fresh water enters into the sea. An estuary filters the water of sediments and other contaminants as it arrives at the ocean or sea. Some areas of the earth the estuary topography is very different than what you see here because the land topography is very different than here. Steep sided estuary forms are called Fjords.
In an estuary (semi-enclosed are) where sea water and freshwater meet can be either positive or negative in that with the positive it is where a river continuously flows into where it meets the seawater whereas negative is where the flow of the river has dried up and the area may become entirely saline. The water within the estuary will be brackish where a healthy balance of freshwater and salt water are coming together. An estuary is like a huge sponge soaking up excess water and returning it to underground and slowing water runoff. They are known to be one of the most productive in the area of organic matter… even more than comparable sized areas of forest lands, grasslands, and agricultural lands. The tides determine the mixing of this area and are actually the dominant influence where the wave action is very active and the fetches are long. The river flow bring nutrients to the area for plants and animals that specifically habitate a brackish environment. This area is also a nursery for sea life creatures as well. An estuary can be a bay, lagoon, sound, or a slough.
The estuary part of these terms is a reference to the water and organisms that are within it and the health of it with regards to Human influence which there are many and have no significance in this earth science lesson however major significance in the long term health of each Estuary known in the world. For instance Chesapeake Bay is a well-known very large estuary fed by many rivers and goes through many states, all the while affected by human influence and a very important habitat for many organisms. For the purposes of this earth cache I limit the considerations to the basic form and the Estuary land/sea form and its components.
Texas has 367 miles of ocean coastline and 12 estuaries. 5 of these are minor estuaries and 7 of them are major. You are standing looking towards one of the 7 major estuaries of Texas coastline.
A wetland associated with an estuary is where the water table meets the land surface and these can be found in many areas along the perimeter edge of estuaries.
Can you see any evidence of a wetland near these posted coordinates where you stand? Using your compass feature on your geocaching device tell me which direction you observe these wetlands.
Looking to the east and south towards the Gulf you can observe:
Wave action
What you are looking at is called Fetch this area has wave action over it driven by wind. Fetch is a term used in geography and meteorology and will determine the erosion and surge of water to an area of shore.
What is the Fetch here today? Would you say that it is;
- Strong with a very active wave action
- Moderate with a few waves traveling northward towards the small creek outlet
- Minimal with very little wind and very little wave action
Brackish water is where salt water and freshwater meet. A common misconception about brackish water is that it is brown. It is not the brackish water that creates the color. The brown that you would perceive as brackish water is actually associated more accurately with the soil in the area of the color than the water itself.
Out beyond where you can see from here to the east is a Barrier Island where Port Aransas is.
The wave action you see here is not action from the ocean in the Gulf of Mexico but is created by the winds. Although there will be a tidal flow and this will affect the waters of the estuary as well it doesn’t have the same effect as the waves on the area of observation.
Using the diagram and observing the area what part of the estuary form would you say that this particular area is in? (There may be one that you observe)
Upland
Marsh
Mudflat
Channel
Study the view in general and use the age of an estuary diagram to determine whether you deem this estuary to be:
A Youthful
B Middle Age
C Old Age
Not a requirement of earning credit for this earth cache but it would be great if you could share a photo or 2 in your log of the area.
Remember that I'm not trying to judge people for getting the answers exact. I'm more interested in knowing people are going out to the location and engaging with the concepts involved. Don't worry about being 'wrong' - use what you know and make a solid effort. Earth caches are supposed to be fun. Please send me your answers via message or email.
Thank you for visiting this earth cache!! And always make sure to plan according to the climate and weather conditions when geocaching.
CONGRATULATIONS LADYBLACKCAT AND CARROT KILLER ON FTF!!!!!!!
