Two Creeks Buried Forest provides a unique,
precise record of the multiple glacial advances and retreats in
this area during the Wisconsinan stage of glaciation. It tells
an amazing story of ice advance and retreat, lake level rise and
fall, forest bed growth and death, lake level rise and fall, ice
advance and retreat, and lake level rise and fall. The outcrop
is located near Two Creeks, Wisconsin after which it is
named.
|
Exposed forest remnants (Photo Credit: John
Hoaglund Photo Date: Friday, May 28,
1999) |
The historic forest became established between
the Cary and Valders glacial substages. After temperatures warmed
and the Cary glacier retreated northward, a mature boreal-like
forest of black and white spruce, hemlock, pine, various mosses and
other plants developed in the Two Creeks area near Lake Michigan.
Shortly afterwards, the advancing Valders glacier blocked off the
northern Lake Michigan drainageway, raising lake levels, flooding
the forest and covering the ground with silt and clay, preventing
decomposition.
Later, when the southern end of the Valders
glacier reached the area, it flattened the forest leaving behind
another clay layer imbedded with logs and other debris. These
layers of clay, silt, sand and the buried forest are visible on a
steep bluff along the lakeshore where wave action and erosion have
exposed the layers which contain long-buried branches, logs, and
stumps of spruce, pine and hemlock trees. Conifer needles, cones,
mosses, and terrestrial snails are also present within the layers.
Unearthed wood, radiocarbon-dated at 11,850 before present,
provides an absolute date on late-glacial sequences in the Lake
Michigan Basin, and evidence that periods between substage glacial
advances were long enough for forests to develop.
Two Creeks Buried Forest is a unit of the Ice Age
National Scientific Reserve and has been a popular study site for
North American geologists, botanists, glacial ecologists and
climatologists. Removal of any material is strictly prohibited. Two
Creeks Buried Forest is owned by the DNR and was designated a State
Natural Area in 1967. Open to the public 24/7/365.
Two Creeks Buried Forest, truly one of
Wisconsin's hidden wonders. If you've ever gone to Door County on
Highway 42 you have also passed it, at the grassy field on Lake
Michigan's bluff at the intersection of 42 and County BB near the
Manitowoc-Kewaunee County line. But you likely didn't see the
buried forest because that's just what it is. You only saw the
grassy field that covers it. The buried forest, dated by scientists
at about 12,000 years old.The first time I heard about it I went to
the site expecting to be awed by a buried forest, until it hit me
that by definition there wouldn't be much more for lay eyes to see
than the grassy field. Still, it's neat to know. At Two Creeks, you
can't see the forest for the lack of trees.
A Geocache Notification Form has been submitted to Thomas A.
Meyer Conservation Biologist, State Natural Areas Program.
Geocaches placed on Wisconsin Department of Natural Resource
managed lands require permission by means of a notification
form.
NOTE: Visitors should
respect a "no hammer, shovel, or sampling" etiquette coincident
with the law that applies in most national and state parks.
Visitors also assume all risks, including those associated with
steep and slumping lakeshore slopes and bluffs. Do not access
bluffs from private property without explicit
permission.
To get credit for this Earthcache, e-mail
me the answers to these questions...
1. Estimate the
height and give the elevation of the bluff.
2. Estimate the
average width of the beach - from bluff to water.
3. Erosion has its
positive and negative effects. Here at Two Creeks Buried Forest,
though damaging and causing safety issues, erosion could reveal
more interesting geological artifacts, such as pine needles, tree
limbs and other forest fauna and flora. Answer the flowing
questions about erosion here: a) Water levels of Lake Michigan ARE
effecting bluff erosion. (True of False)Why? b) Human contact here
is speeding up erosion on this bluff. (True or False) Why? c) Since
we do not have hurricanes here in Wisconsin, weather is NOT a
concern for erosion (True or False) Why?
4. Take a pic with
your GPS in it and include yourself (if alone, just the GPS) or
your group, next to the information plaque, located near the posted
coordinates.
Enjoy!!!
References:
Hoaglung, John , et. Al.,
University of Michigan, retrived from
http://www-personal.umich.edu/~hoaglund/TwoCreek/twocreek.html
National Parks Service, Geology of
Ice Age Reserve of Wisconsin - NPS Scientific Momograph No. 2,
retrieved from
http://www.nps.gov/history/history/online_books/science/2/chap2.htm
Wisconsin Dept. of Natural
Resources, retrieved from
http://dnr.wi.gov/org/land/er/sna/sna50.htm
http://www.nps.gov/history/history/online_books/science/2/chap2.htmology