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 * __This is our geology class field trip site.

This is not spring and we're doing something new.

Stop 1 - Wequiock Falls, Wisconsin__** (photo from: [])

**Wequiock Falls** is located in the Niagara Escarpment, on the Maquoketa Formation, in Brown County. Wequiock is made up of different sediment layers, including different types of dolomite, shale, and sandstone. The Maquoketa Formation’s rock is easily eroded, therefore less resistant to the overlying Dolomite rock. The falls were created by glacial movement which allows the water to flow in the opposite direction of other rivers and creeks. Wequiock has a twenty-five foot fall, and seems to only run during the spring and early summer months. Water that feeds the falls is mainly from precipitation. There is New Franken Swamp a few miles south that also feeds Wequiock, but with out rainfall, it would dry up very quickly.  The water from a stream or river flows over a large normally hard rock, and falls over the rock creating a waterfall. When the water hits the bottom of the rock it carves away the softer rock and mineral deposits, where it forms a pool of water; eventually that pool starts to rotate like a saw that cuts into the rock (which is typically shale, sandstone or some other sedimentary rock) and eventually wears it away until the harder rock can’t be supported and it breaks off and falls into the river, this is called undercutting. This will eventually lead the water to recede upstream.
 * Click here to see the different layers of Wequiock Falls! **

Waterfalls take thousands of years to fully form, but the processes that form the waterfall to begin with also contribute to the destruction of the falls. When water falls are forming the hard rock on the surface is slowly getting eroded by the rushing water before the fall and causes the hard rock to overhang. After a long period of time the softer rock below the surface rock becomes exposed and large chucks of rock fall into the plunge pool causing the waterfall to retreat backwards. This is the beginning of the deformation of a waterfall. Every waterfall recedes, Niagra Falls for example is retreating at a pace of 1 meter per year. As this process continues to disintegrate the waterfall it can lead to the formation of a different type of one of the 10 different kinds of waterfalls. This process can also cause the stream to take on a totally different path where the stream can flow naturally.

Waterfalls are classified and grouped into different categories and classes depending on the amount of water that passes over them and how it was formed geologically. For example Wequiock Falls is s punch bowl waterfall because the water descends in one ribbon and then spreads out into a large, wide pool. Its class would be a one or a two because it doesn’t flow continuously and there is not much water flowing over the falls.

= =

(photo from: [] and [] )
 * __Stop 2 - Potawatomi State Park - Observation Tower View__**

(underlying geology from: [] and [|http://www.dnr.state.wi.us/org/land/parks/specific/Potawatomi/nature.] []

=__History__= The park is named in honor of the tribe that inhabited Green Bay’s shores and islands when Europeans first settled the area. The tribe called themselves “Bo-De-Wad-Me” which means “keeper of the fire.” Eventually the spelling and pronunciation were changed to “Potawatomi.” Potawatomi State Park was established in 1928 after the Wisconsin State Legislature had purchased the land earlier that year. Quarrying- Door county's first industry and it's first export- began here in 1834. The quarrying process was found to be not as successful in this area as in other nearby quarrys. Once known as Government Bluff the park has been owned by the U.S. snce 1837. At that time it was considered a prime location for a fort in case of war on Canada. Early idustry began in 1837 when Peter Sherwood settled on the point just north of the point, and therefore the point was named after him. Frank Sawyer farmed and traded with Native Americans, eventually the Harbor became known as Sawyer Harbor.

Quarry and park establishment history courtesy of Erin Brown- Staff member at Potowatami State Park =__**Geology**__= The [|Niagara Escarpment] was scraped by glaciers to form layers of limestone along the shore creating [|cliffs]. The Potawatomi State Park is filled with dense forests containing a variety of trees. Sugar maple, basswood, white pine, red pine and white birch cover most of Potawatomi’s 1,200 acres. Beech trees are also quite common around this area. They are only found in Wisconsin within a few miles of Lake Michigan. The trails of Potawatomi State Park, gradually climb to a high point 120 feet above the level of Sturgeon Bay. Athough Potawatomi is a base for boating, canoeing, kayaking, fishing, scuba diving, and waterskiing on Green Bay, the rocky shore doesn't have a beach. There are at least 50 species of birds that nest in and around the park's area, and several can be seen catching fish along the Lake Michigan shore. One to look for in the forest area is the [|pileated woodpecker]. On a clear day, the view from the park's observation tower reaches 16 miles across Green Bay and two and a half miles of shoreline.

=**__Coastal Processes__**= While looking at the large picture of the park, we can see that erosion is one major coastal process taking place. As we can see, there is a little piece of land that is located in the middles of the body of water. It is most likely that this piece was attached to the land in the foreground. Sediment distribution/movement is taking place. If you look closely at the picture, you will see the darker areas of water. This represents sediment movement/distribution. Also, if you look closely at the left hand side you can see some algal growth in the water which can be a result of eutrophication, which we know is caused by excess nutrients in the water. If one were to look at the smaller picture, the one beneath the big one, we can see that the water level used to be much higher than what it is today. This is based upon the fact of the small rock cliff in which the trees are situated on top of. Since the water has subsided, the rocks on the face of the cliff have begun to topple over.




 * __Stop 3 - Historic Lake Michigan Levels__**

(image from: [])

**__History:__** The history of Lake Michigan goes back approximately 1,000,000 years when glaciers, up to 6,500 feet thick, covered most of the Midwest. As the glaciers moved slowly back and forth, gouges were created that were then filled with the melting glacier ice. Lake Michigan is now approximately 300 miles long and averages 75 miles across. It is considered to be the third largest of the Great Lakes, and it is the only one completely within the United States. (Image from: http://www.ho-chunknation.com/UserFiles/Image/OOP/Jean%20Nicolet.jpg)

Lake Michigan was discovered by Jean Nicolet, in 1634, as he was trying to find a northwest passage to the Pacific Ocean. Over the years, Lake Michigan has served as drinking water, transportation, and a tourist attraction. During the 1960’s Lake Michigan was also used as a recreational, agricultural, and industrial dumping grounds. These “zones” ended up being piles of “stinking algae”. By the early 1970’s the Clean Water Act stopped this pollution and started the cleanup process.

Lake Michigan’s water levels fluctuate from month to month. Typically the highest levels are in October and November. The lowest levels are typically during the winter months. The highest levels were during the summer of 1986, when the Lake was charted at 5.92 feet above datum. The lowest levels were recorded in the winter of 1964 when the water reached 1.38 feet below datum.

Lake Michigan is also a home to many fish and other organisms. Lake trout, yellow perch, largemouth bass, and carp are all native species to Lake Michigan. Some species of salmon were also introduced to decrease the alewife population, which caused the salmon population to increase greatly. sources for History: [], [], [], [].

**__Formation of Lake Michigan and Great Lakes:__**

The most recent ice age that we have experienced is called the Pleistocene Epoch. During this time a lot of North America was covered in 4 km (about 6,500 feet) thick glaciers that were continuously advancing and retreating. The climate was extremely cold and allowed such formation of glaciers. During the advancing stage of glaciation is when the majority of the valleys and holes were carved into the landscape. During the retreat (melting) of the Laurentide Glacier, about 14,000 years ago, is when fresh water filled in these valleys and holes developing what we call the Great Lakes. (Image from: http://www.uwsp.edu/geo/faculty/ritter/images/lithosphere/glacial/piedmont_glacier_Baffin_GSC_2crev.jpg)

The glaciers carved out specific lobes (lakes) because of the underlying geology of the landscapes. The areas that were merely scraped by the glaciers had a very tough kind of bedrock that resisted breakage. Whereas the carved out great lakes, had bedrock composed of soft shale and sandstone which allowed the glacier to plow its way through the landscape. Valleys also provided an easy route for glaciers to travel. While the glaciers melted in soft bedrock it continued to erode the valleys and holes into much deeper and wider features. The meltwater that ran off the glaciers gathered up and pooled into the newly formed great lakes (specifically talking about Lake Michigan).

Glaciers also left behind all different kinds of features due to sediment it carried and how it carved out the landscapes. When sediment is deposited it creates moraines, which are long piles of loose sediment. Glaciers can also create features like kettles, terminal moraines, end moraines, high ridges, eskers, drumlins, and leave behind huge erratic boulders.

Glacier are extremely heavy chunks of ice and actually cause land to sink or push it down. So, when the glaciers began to melt the land began to rise slowly and also caused huge changes in the depth and size of the drainage patterns of the great lakes. The uplifting still occurs very slowly in the northern parts of the basin. But because the land continutes to rise it can still cause fluctuations in the size/depth.

 



Lake Michigan has been slowly rising since 2007. Due to the cold temperature and the amount of rain and snow, it is currently about 10 inches higher than a year ago. The US Army Corp of Engineers predicts that it will go up throughout the summer as well. Within 16 months Lake Michigan has raised more than two feet, and continues to raise daily.
 * __ Recent Levels: __**

Lake Michigan fluctuates about a foot a year, and has since records were first kept in the 1800’s, and peaks in late summer. The University of Rhode Island, found that the Great Lakes water has fluctuated by only seven feet for thousands of years. According Keith Kompoltowicz, an Army Corp Meteorologist in Detroit, the water level usually begins to rise around March or April, but in 2008, it began rising in January and continued to rise through July.

Between 1972 and 2008, the amount of ice covering Lake Michigan declined by 30 percent, leaving the water about to evaporate all year long. In combination with the year-round evaporation, there is a growing population drinking the water, which is causing a larger drop than ever in the lake levels.   In the 1990’s we had near record low, well below the long term average, for an unusually long period of time. Again in January of 2007, there was a drop in levels as well, headed toward record low levels. But, there was a turnaround in winter 2008 and the water levels began to increase and are continuing to.

Weekly Levels for November 6th:

**Expected water level for** **November 6, 2009,** 578.41 feet. **Chart datum,** 577.5 feet. **Difference from** ** Oct 6, 2009, **0 inches.
 * Difference from** ** Chart Datum, ** +11 inches.
 * Difference from Nov 6, 2008, ** +12 inches.
 * Difference from long-term monthly average level for November, ** -4 inches.
 * Difference from highest recorded monthly mean level for November **, -43 inches (1986).
 * Difference from lowest recorded monthly mean level for November **, +26 inches (1964).
 * Projected change in levels By December 6, 2009, ** -2 inches.

[information for Recent Levels- []. []. []. [] ]

(Image from: http://learn.uci.edu/media/OC08/11004/OC0811004_FreshWater.jpg)
 * __ Effects on harbour and people: __**

The Great Lakes are responsible for one fifth of the world's fresh water. According to Glen Nekvasil, part of the Lake Carriers Association, every one inch drop in lake levels means that each 1,000 foot freighter has to cut its load by 270 tons. Due to the near record low water levels in 2008, human polar bears (Polar Plunge) taking their annual New Year's Day plunge off the Door Peninsula, had to navigate around yellow caution tape to avoid cutting their feet on an offshort shipwreck. Docks become useless, hull-cracking hazards, such as sandbars and rocks, for recretational boaters, marina operators with steep dredging bills. Normal water levels are important for Great Lakes shipping industry because a "laker" can carry five million more pounds of cargo. Small boats benefit from this too. About two to three years ago, we were not able to put large sailboats in because it was like dropping them into mud. The 1960 dredging and riverbed mining on St. Clair River resulted in permanant water loss of 16 inches long term. It also resulted in water flowing down river and into Lake Erie.

The coast of Lake Michigan is constantly exposed to erosion because of the waves, currents, and the wind. The waves also carry sedimentary material, called littoral drift, up and down the coast. How fast the water is moving determines what is being moved and how far that material is going to go. This process is what can cause the shore to wash away. The shores of Lake Michigan are “nourished” by eroded material from other places. ([])

In 2008, Lake Michigan came to an all time water level low. Fortunately, the levels have risen 9 inches since then, because of the wet winters. This low water level has had effects on all the people who enjoy Lake Michigan every year and those who depend on Lake Michigan for business. Low water levels can cause hull-cracking on boats for recreational boaters, it can also cause freighters to lop their cargo loads. ([] )

[information for effects: []. __ []]


 * Stop 4 - Whitefish Dunes State Park / Cave Point County Park** __



**The Shape of Whitefish Bay**
The shape of whitefish dunes is shaped in this way because of old coarls and plant life. This formed a bowl shaped structure of limestone called the niagra escarpment. The bowl shape is formed because Glaciers carved away lose materials and layers of rocks to form and expose escarpment all over and through the wisconsin area. Escarpment is a transition zone between to areas usually forming a cliff or hill or area of sharp or steep elevation. Another interesting fact on how the beach is formed is from wind. It is because of this, the wind blows the sand around continually shaping the dunes.

Schematic cross section of a cuesta, dipslopes facing left, and harder rocklayers in darker colors than softer ones.
 * Escarpment Diagram-**

The rocks around Door County tell a story of what was once here. The exposed dolostone give clues of a shallow warm sea once covered the area around 425 million years ago. This time period is known as the Silurian Sea. Clues to the age of the rock are found in the fossils. These fossils were made when shifting sediment on the bottom of the sea covered the coral or shell. Once covered, water and dissolved minerals slowly replace the original material. As the rock around the fossil wears away, it is revealed to you. Look for fossil sea shells and coral reefs in exposed rock throughout the Door Peninsula. Dolostone forms what is known as the Niagara Cuesta. Shaped like a giant bowl this band of rock goes from Wisconsin around the north end of Lake Michigan and Huron to Niagara Falls. The Door Peninsula and Niagara Falls lie opposite each other on the rim. Over millions of years the once-flat sea bottom deformed into the bowl. Only edges of the cuesta are seen above ground. The remainder lies buried below several layers of rock. The Niagara Escarpment is the cliff part on one side of the cuesta. Rocky bluffs of Potawatomi, Peninsula and Rock Island State Parks are examples of this edge. Here is interesting experiment for one that is on the beaches of Whitefish Bay. Push a magnet into the sand and discover clues to its origins. Magnetite, an iron mineral found in the Lake Superior basin, will cling to the magnet. These sand grains are debris that glaciers eroded from the bedrock of Canada and dumped into Lake Michigan.



(photo from: []) This area is a serene area to travelers because of its coastal onlook of geography due to its location.The enhances and the stability of plant life and corals, and tube-forming sabellariid worms formed these reefs ledges, 15 feet (4.6 m) arches, and spur-and-groove Michigan and Wisconsin waters. The pygmy whitefish is known to occur only in Lake Superior.

Over thousands of years, accumulating sand has closed off Clark Bay to create Whitefish Dunes and Clark Lake. The formation of the dunes and the closing of Clark Bay took a long time. About 5,000 years ago, Cave Point defined the bay. When water levels rose, the point was submerged, but remained as a sand bar. This slowed down water currents, causing the sand that water carried to deposit southwest of the point. When the water began to recede, the first bits of what would become the dunes peeked above the lake level. Since, they have continued to grow, eventually closing the bay and forming what we know today as Whitefish Dunes.



**Geology of the Dunes:**
Much can be learned about the geology of this area just by observing the rocks. Exposed dolostone that covers the area tells us that a shallow warm sea once covered this area. The time period this occurred was around 425 million years ago is known as the Silurian Sea. The exposed rock causes the area to be more rugged and not just a smooth sandy area. The sand in this area is also full of magnetite and is the result of glaciers that eroded from the bedrock of Canada and were dumped into Lake Michigan.

Fossils in the area also tell us the age of the rocks. These fossils were made when shifting sediment on the bottom of the sea covered the coral or shell. Once covered, water and dissolved minerals slowly harden, replacing the coral or shell. As the rock around the fossil wears away, then you are able to see it. Fossil sea shells and coral reefs can be found in exposed rock throughout the Door Peninsula.

The bluffs and dunes created in this area as a result of the glaciers are some of the highest in Wisconsin. Drying sunlight and wind are a constant hazard for this beautiful area, with low-spreading plants being it's only protection from erosion. Marram grass spreads its roots under the sand, connecting tightly like a web and stabilizing the sand, which enables other plant life to take root in the area also. Wind is also a major factor in the constant changing and reforming of the dunes as it comes uninterrupted across Lake Michigan and smacks right into the existing dunes.

Dolostone forms the Niagara Cuesta. This band of rock goes from Wisconsin around the north end of Lake Michigan and Huron to Niagara Falls and is shaped like a huge bowl with the Door Peninsula and Niagara Falls opposite each other on the rim. Only edges of the cuesta are seen above ground, with the rest buried below many layers of rock, and the Niagara Escarpment being the cliff part on the one side. []

=**History of the Dunes:**=

The Whitefish Dunes is one of the most visted parks in Wisconsin. The dunes are said to be protected by a group of roots that helps sheild the dunes. In 1930 the Whitefish Dunes needed to be preserved. What many people found on the dunes was rare and was stated as one of the "best sand dunes" so they wanted it to be protected and not harmed by development. The state park was established in 1967. 230 acres of the 867 acre park was named as a state natural area in 1982. The people or Door County and the Wisconsin Conservation Commission were the people to get this located protected. The primary reason many people wanted to settle here was because of the fishing oppportunities. This location has been placed on the National Register of Historic Places. It is said to hold great potential for future research.  Other information regarding the history can be found on this website: [|**http://www.dnr.state.wi.us/Org/land/parks/specific/whitefish/history/**]

(photo from: [])

=__Stop 5 - Karst Topography and Door County__=

The term karst comes from the German word for barren land. Karst topography includes things such as caves and underground channels. These caves and underground channels are formed when water erodes rock from underground. Once there is enough bedrock eroded away, the ground can collapse and create a sink hole. In places such as Florida these sinkholes have engulfed houses and cars. Inside some of the caves there are calcium deposits called speleothems. **(1)**
 * __Karst Topography: An Overview__**



Karst Topography is where there are streams that flow underground and erode the limestone or dolomite bedrock, in addition to weaking some of the rocks above. Eventually, a weak area of the surface is eroded away and surface water flows down the hole to join up with the underground streams and groundwater.

Karst Topography is marked by sinkholes where water flows from above ground into underground natural waterways. This is caused by groundwater eroding away sedimentary rock such as limestone creating things such as caves. **(3)**

__**Hazards of Karst Topography**__ //**Sinkholes:**// Sinkholes are a problem in Wisconsin but they tend to be far smaller than those seen in Florida because Wisconsin's rocks are Dolomite which is much less susceptable to erosion than the limestone rocks that make up much of Florida's land. In Florida, because the land is made of limestone which is more readily eroded, sinkholes there are much larger and have been known to ocassionally swallow up entire houses. **(6)**

Below is a photo showing the progression of water eroding rock that creates sinkholes.

**//Well Contamination//**//:// There are several counties in Northeast Wisconsin, including Door County, that have Karst topography and experience some problems characteristic of Karst topographic areas. One of the more prevalent issues facing Wisconsin residents in those counties is Well contamination. “Karst areas are those places in Wisconsin with thin soils that overlay limestone. Sinkholes are often found in these areas, and the sinkholes or cracks can allow pollutants to easily reach groundwater.”- WLWCB Chairman Mark Cupp. Much of the pollutants that are reaching these local wells are waste products that are being spread on farm land. When a farmer spreads manure, especially before the spring melt, it can easily get washed into the water table through the hollow spaces created by dolomite erosion. When this happens it contaminates drinking water wells with waste products. Recently it has become an even larger problem because five counties in Wisconsin with Karst topography have been experiencing increased numbers in their farm herds. The increase in herd size not only increases the amount of waste produced by the herd but also the amount of food needed to be grown to keep animals in good health. The more food the farms need to produce, the more manure they will be spreading on fields which increases the chance of the pollutants reaching groundwater and wells. **(8)** //**Well Contamination Cont’d:**// According to research done by Maureen Muldoon and Fred Madison, A co-author of the Northeast Wisconsin Karst Task Force Report and a soil scientist, since the Karst areas have cracks, caves, sink holes and fractured bedrock water is able to travel very quickly and uninhibited. Wells in the area can reportedly fluctuate up to 100 feet up or down in a single year. Water quality will also vary and Muldoon suggests that wells in the area should be tested more than the previously recommended once a year. Muldoon found that even routinely about 1/3 of the wells in Door County tested positive for coliform bacteria. Due to all of these problems in the Karst area Muldoon suggested that there should be different restrictions on manure spreading for different geological regions of the state. The regions with Karst topography should have stricter guidelines to protect their groundwater supply. There is also karst topography present in Southwest Wisconsin but because it has a layer of red clay overlying the dolomite, it is more protected against water erosion and the groundwater pollution that can result in bedrock erosion. Red clay is not very permeable which is why it protects the dolomite in that region. **(9)**

Below is a photo showing manure runoff during snowmelt. In areas with Karst topography this runoff easily flows through the cracks and underground caves. Eventually it can find its way to groundwater and the water table, contaminating wells.

In Door County and other karst regions the bedrock is often eroded making cracks and paths which allow rainwater to easily reach the water table as shown in the diagram below. Sinkholes are most likely to occur in the Dolomite horseshoe shown on the map above.

Accoording to Maureen Muldon a co-author of the Northeast Wisconsin Karst Task Force Report, which shares that there should be a tighter control over Manure spreading in certain geologically fragile counties in Wisconsin. Maureen indicates that maure spreading contaiminates the ground water in these fragile areas, because many of the biggest dairy counties in Wisconsin is riddled with sinkholes, fractured bedrock and uninhibbited underground drainage, making manure spreading during the snow melt problamatic for the underground water. She indicates that the ground water runs extremely fast in these areas complicating the problem, causing the need for more contriols over the manure spreading.
 * (13)**

__**References:**__
 * 1. (Information from: [] )
 * 2. (Photo from: [] )
 * 3. (Information from: [|http://www.watersheds.org/earth/karst.htm)http://www.thebubbler.com/forums/natural-sciences-scientists/9915-karst-topography-wisconsin.html])
 * 4. (Photo from: [])
 * 5. (Photo from: [])
 * 6. (Information from: [])
 * 7. (Diagram from: [] )
 * 8. (Information from: [] Fyksen, Jane. “Karst Area: Groups Calling For Legislation”)
 * 9. (Information from: [] Fyksen, Jane. "Researchers: Ample Evidence Karst Makes Northeast Vulnerable to Manure Problems.")
 * 10. (Photo from: [])
 * 11. (Diagram from: [])
 * 12. (Map from: [])
 * 13. (Information from [])