“A state park vehicle sticker is required to do this EarthCache.
Stickers can be purchased upon arrival at the property.
Please remain on trails at all times.”
This hike will take you along the "Red " trail.
During winter, the Red trail is also used for cross country skiing.
Limestone:
Four hundred million years ago central North America was located near the equator. A shallow saltwater sea covered the area at that time. Corals, brachiopods, crinoids and other early marine life lived and died here. As time passed, their skeletal remains (calcium carbonate) accumulated, layer upon layer. Time, temperature and pressure altered these layers transforming them into limestone, creating what would later be the area known as Cave Point. As time passed, magnesium would replace some of the calcium in the limestone, altering it into a harder form of rock called Dolostone.
The Laurentide Ice Sheet:
During its peak, the Laurentide Ice Sheet was almost two miles thick and covered over 13 million sq. km (5 million sq. miles). The most recent activity of the Laurentide Ice Sheet was called the Wisconsin Glaciation Episode. The Wisconsin Glaciation Episode began some 100,000 years ago and ended around 10,000 years ago. These glacial advances and retreats carved and eroded the limestone beneath them. Eventually shaping the rocky outcrop that is Cave Point.
Sandbar Deposition:
With global warming came glacial melt-off and the rise of lake water levels. Cave Point had once again become submerged. Passing Lake currents then deposited sand upon the point. The accumulation of sand would continue over the years, creating a sandbar. This growing barrier, protruding into Lake Michigan, slowed water currents that followed the lakeshore toward the south. This caused even more sand to drop out of suspension, lengthening the sandbar to the southwest.
Long Shore Drift:
Creation of this sand beach was due in the most part to wave action. Waves, washing onshore (Swash) move in the same direction as the prevailing winds (southward). These waves collect sand from the bottom, wash in, and deposit some of the particles on the beach before retreating. The retreating (offshore) backwash, due to gravity, always flows perpendicular to the shoreline. As this backwash loses energy, it drops more of the sand particles during its retreat. The next wave again picks up the particles and moves them slightly further down the beach. This zigzagging of wave action causes a continual lateral movement of sand along the shoreline in one direction. This process of sand movement is called long shore drift and can be observed on all beaches. Long shore drift is the main cause of long strips of coastline being covered in sand. As the water receded once again, the first bits of what would become sand dunes peeked above the lake water. These dunes would continue to grow, creating what we know today as Whitefish Dunes.
In Unison:
Limestone deposition and glacial erosion helped to form Cave Point. Cave Point slowed water currents which assisted in sandbar growth. Long shore drift and the growth of the dunes would eventually close off the bay to the west of Cave Point, forming what is now..........Clark Lake.
The Strand:
A Strand, or Strandplain, is a broad belt of sand along a shoreline with a surface exhibiting well-defined parallel or semi-parallel sand ridges separated by shallow swales. (Wikipedia)
The Lake:
Clark Lake is an 865-acre drainage type lake with very clear water quality and a maximum depth of 25 feet. Its’ bottom is 45% sand, 10% gravel, 30% rock and 15% muck. You will not see the actual Lake on this hike.
From the parking coordinates take the red trail west until you come to “Old Baldy”. Email your answers to the questions, to me, using the link in my profile only. If your answers are not recieved by me in an appropriate amount of time, your log will be deleted. Photos are accepted and appreciated as long as the answers to the questions are not revealed. You do not have to wait for confirmation from me before logging this cache as completed. Most of all……learn……and enjoy the view.
1. What is the main cause of this long strip of coastline to be covered in sand.
2. When were the first sand dunes at Whitefish Bay created? (from signage along the red trail)
3. What is the height of Old Baldy above the Lake Michigan water level? (from signage at top of Old Baldy)
EarthCache placement form has been submitted to
Carolyn Rock
Natural Resource Educator
Whitefish Dunes State Park