Geology story
As I walk along a path near my home, I can gaze up
into the hills of the Boyne Highlands or Nub's Nob ski areas and
enjoy the beauty of the varied terrain around me. What helps to better connect
me to this land though, is to create a sense of place, to understand how these
hills came to be. As a young girl studying Michigan history in school,
we learned all about the great sheets of ice that covered our land
which created its varied topography and lakes. We never got into the more in
depth specifics regarding the mechanics of how the glaciers worked their magic
and thus never came to understand words such as recessional moraines
or outwash plains. Words which give better meaning to what I am
looking at or walking upon as I take a stroll out my door.
As glaciers advanced over Michigan 10,000 to 12,000 years ago, they took the path of least resistance, widening river valleys to form today what is known as the Great Lakes. As these glaciers moved over the land, they operated as a conveyor belt, scooping up debris as they went along, not bulldozing the land as you would think, and then as they melted and began to retreat, hills and valleys were created through this melting as they dropped the debris they had picked up along the way.
As
the ice sheets melted, their retreat was done in a stop and go fashion. When
they stopped, the glacier dropped the material it was holding known as glacial
till. This till as it was deposited, formed hills known as recessional moraines
such as what you'd find at Boyne Highlands or Nub's Nob. The flatter
areas in front of the moraines were known as outwash plains, where
the melting water containing smaller particles of debris such as sand, moved
away from the moraines. This is a very simplistic explanation of the process of
glaciers and the story of how my local landscape was formed, but to me I find
it interesting to begin to connect the dots of how things came to be. To begin
to understand why the soil under my feet is comprised of sand or why some
places are hilly while others are not.
Now,
as I walk along the path near my home, I no longer just see hills and valleys,
but think instead of the huge glaciers that carved out the story of my
landscape. There is much more to learn and so many questions to be unlocked
regarding this story but that is what gets me out the door over and over
again.
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