I must stress that this cache is only accessible by a water craft via Lake Huron. If you are not comfortable navigating the waters of Lake Huron, do not attempt to do this cache. Lake Huron can be dangerous at times for small water craft such as kayaks or canoes. Before attempting this cache, use common sense and a few safety procedures, such as telling someone where and what you will be doing and wearing a life jacket. Choose a day when the winds are calm and out of the south (off shore). I did kayak to these spots on a day when the wind was 5 to 10 MPH out of the south. I started out by 9:00am so the waves didn't have a chance to build. Care should be taken, however you choose to access this earthcache as many rocks are in the waters. Some are visible above the water's surface, others are just lurking below the surface.
Since the land beyond the shore is privately owned, do not trespass on it. It has always been a private, gated resort since 1896. If you step on shore and you could be trespassing.
A business in the city of Port Austin offers tours by boat of Turnip Rock. Others rent kayaks or jet skies.
I am excited about the Point Aux Barques area. I find that when bedrock is exposed on the surface, I feel very connected with Mother Earth. Our planet has been described as “The third rock from the sun”. Living in south east Michigan all I can say is, “Where's the rock?”. I learned of this place in the early 1970's when I took part in a high school Earth Science field trip to the tip of the thumb. Back then, this area was not a gated community and we were able to drive up the the house that sits near by.
If you are able to find this earthcache, you will be rewarded with some of the prettiest views in southern Michigan. Everyone that received their grade school education in Michigan learned that glaciers pushed their way over Michigan several times. The result is glacial drift averaging 200 to 300 feet deep covering on top of the bedrock. The thickness of drift has measured over 1,000 feet in a few Michigan locations. Rarely can we see exposed bedrock that has been sculptured by non glacier forces. This is one of the locations in southern Michigan where the sandstone bedrock is exposed at the surface. The amount of shoreline that has exposed sandstone is about one mile, but a lot of beauty has been sculptured in the stone.
Caves can be created by one of three basic actions. Lava tube caves are formed when volcanoes spew forth molten, liquid rock. The lava flows forms outer layers which cool and become solid while the molten lava continues to flow inside the cooled surface. The cave is formed when the lava drains from the lava tube.
Solution caves are formed by the water flowing through fractures in limestone, dolomite, or gypsum. Acids dissolved in the water react with the rock, dissolving it and creating a cave. These types of caves will typical contain features created from the deposition of the dissolved minerals. Some of these features are stalactites and stalagmites are the two most commonly known.
The third type is a sea cave. Sea caves are created when the wave action wears away shoreline rock at a weak point. Through time this opening would be enlarged, thus creating a cave. Sometimes the erosion process continue until the cave breaks through to another area of shoreline. This would be called a sea arch. A small, mostly under water sea arch can be seen west of Turnip Rock.
It is the third type of cave that has form here. This area has been shaped by wave actions since the glaciers retreated for the last time. For thousands of years the waves have pounded the exposed sandstone, causing more erosion where weakness existed in the rock. This cave system was formed in a headland (an area of land adjacent to water on three sides) when the water level was higher. The cave system here is a combination of several sea caves that formed. Some have connected to form two arches. The largest arch is closest to the cliff, the other forms a rather small opening near the shoreline. You will be able to see different layers in the sandstone. Some will have a diagonal marking of how the sand was deposited. Some bands do not display this feature.
Be sure to check out the other earthcaches I've placed in this area.
Port Austin Sea Caves
Point Aux Barques – Turnip Rock & The Thumb Nail of Michigan
To claim your find for this earthcache you will need to perform the following requirements:
- How many cave opening do you see?
- Estimate how much higher the lake level had to be to form these caves?
Not required but always a pleasure to see, please post your photographs too.
Please email your answers to the cache's owner by clicking here. Which will open a new email with the questions in the body. Just add your answers.