I have loved rocks for much longer than I
have been making silly puns with my last name. I used to pick them out of the
gutters of the sleepy streets of my tiny hometown and sort them on foam trays.
My categories included peach-colored pebbles, other colored pebbles, and
pebbles that look like mini food items. Any vacation, canoe trip, or walk
resulted in pockets full of interesting rocks that caught my eye. You might
know someone with a similar addiction.
I often notice a familiar gleam in the eyes
of kids (and adult kids) when they see the shelves of rocks and minerals in our
Collections Room. Toddlers grasp polished agates with chubby fingers, little
prodigies recite the rock cycle, and adults marvel at the size of quartz
crystals.
It is fun to share stories of the rocks with
visitors. Over the years, I have learned enough about geology to feel a sense
of wonder at the incredible history and significance of each shiny pebble and
handful of sand. Beach days have been transformed.
One of my college classmates summed it up on
a trip to southeast Utah when he exclaimed, “Geology is EVERYWHERE.”
Geology really is everywhere. If you go out
to your landscaping rocks, or even onto the driveway, you can find a whitish
rock speckled with black. It is most likely a piece of granite. This particular
rock, the one in your hand, was once as much as 30 miles deep within the
Earth’s crust. Pieces that broke off as it bounced along on its way to you may now
be forming sand castles on a beach in Florida. It is here in Wisconsin because
of the incredible power of glaciers to shape the landscape.
Near that chunk of granite, you might find a
smooth gray rock called basalt. It probably originated as lava that spewed
forth from a fissure volcano in the Lake Superior basin about 1.1 billion years
ago. Air bubbles in the lava, now frozen in the solid rock, provided a space
for our beloved Lake Superior agates to form.
If you poke around in your driveway or
landscaping, you may come across a shiny pebble with red and black stripes or
small burgundy dots. This is one of my favorite rocks, if one could ever choose
a favorite. Some folks call it jasper, but the geologists call it Banded Iron Formation
or BIF. The layers of black and red are made of iron bonded with oxygen
(hematite) and silica bonded with oxygen (chert). The iron and silica probably
originated from volcanic activity. The oxygen came from the very first
organisms that could do photosynthesis! Rocks and life go hand-in-hand, in ways
we can hardly begin to imagine.
BIFs have an incredible story and great
significance in the history of our planet. On Wednesday, July 18, Northland
College geology professor Tom Fitz will tell us all about it at 7:00 p.m. at
the Cable Community Centre. This free lecture is part of the Joseph Jenkins
Lecture Series put on every summer. If you come, beware: your beach days may be
transformed. Geology is EVERYWHERE!
For over 44 years, the Museum has served
as a guide and mentor to generations of visitors and residents interested in
learning to better appreciate and care for the extraordinary natural resources
of the region. The Museum invites you to visit its facility in Cable at 13470
County Highway M. The new exhibit, STAR POWER: Energy from the Sun, opened in
May 2012 and will remain open until April, 2013. Find us on the web at www.cablemuseum.org
to learn more about our exhibits and programs. Discover us on Facebook, or at
our blogspot, http://cablemuseumnaturalconnections.blogspot.com/
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