Thursday, October 18, 2018

International Archaeology Day 2018

Happy Earth Science Week 2018!

The last day of Earth Science Week is designated as International Archaeology Day!

I'm don't know a lot about archaeology, but I know someone who does!  My friend Dr. Kristin Landau is an Assistant Professor of Anthropology at Alma College.  I asked her to answer five questions about archaeology.  This is what she had to say.

On site in Honduras - I don't think dogs are essential to archaeology...I could be wrong. (Photo courtesy of Kristin Landau)

Question 1:  What is archaeology?
Archaeology studies past people through the artifacts we leave behind. Did you know archaeology is actually one of the FOUR branches of anthropology?! The other three branches are cultural, linguistic, and biological anthropology. As a whole, anthropology is the study of humans, and so archaeologists are interested in human groups who are no longer around today. The only way to study them is through all the stuff they left: buildings, mounds, pots and pans, tools and the like.

Question 2:  Why is archaeology important?
Archaeology is important for three big reasons. First, archaeology shows us the full range of how humans make a living on Earth. Of course we can take a plane and fly to every country, but all the people around today only represent a small fraction of all the cultures that have ever existed. So archaeology helps us know how humans lived from millions of years ago to today.

Second, archaeology teaches us lessons about the past so that we can avoid repeating our mistakes. If we know what caused something bad to happen, we can prevent it in the future. But also, sometimes people in the past did things in better ways, and we can also learn from that.

And last, archaeology is important because it connects us to our heritage and identity. In our world today of digital technologies and vast (online) social networks, we’ve lost a sense of our history and belonging. The physical parts of archaeology—the buildings, pots and pans, tools, mementos, cherished items—remind us of who we are. They restore a sense of identity. Preserving those items connects us to our history, to passed loved ones, and even our heritage. Think about meaningful objects you have – what is it about them that creates meaning? How do you feel when you think about them?

Question 3: How does someone become an archaeologist?
Discovering archaeology is always fun. Archaeology is rated the #5 best job in science! Most jobs in archaeology require a college degree, and some require a Masters or PhD. After an archaeological field school, you can always work as a “shovel bum” going out to conduct surveys or excavate a piece of land. Usually people with an MA or PhD are more involved with managing archaeological excavations, and writing up reports to let the public know what’s going on. In the United States, most archaeologists work in Cultural Resource Management (CRM). They could work for private CRM firms, or for the State Historic Preservation Office or Department of Transportation. Some archaeologists also work in museums and also manage the museum’s artifact collections or put together exhibits. A small number of archaeologists also work as professors – they teach archaeology during the school year, and conduct research projects during the summer.

Excavating a Maya ruin in Honduras (Photo courtesy of Kristin Landau)

Question 4:  Why did you get involved in archaeology?
I got involved in archaeology during my second year of college. I wanted to go to another country and see how people lived who were completely different from me. I ended up on an archaeological project in the Central American country of Honduras! The ancient Maya had a city in the very far western part of that country. Fourteen years later, I am still doing archaeology in Honduras, now as a professor. I hope that I can help make life better for the indigenous people there by offering jobs and teaching their kids about the ancient Maya and archaeology. This past is theirs to know about, identify with, and feel a sense a belonging to.

Question 5:  #5 How can the public help archaeologists?
Thanks for asking! The public can help archaeologists in a few ways:

  • Attend your state’s archaeology and international archaeology day! (10/13, and 10/20 in Michigan)
  • Visit local museums or become members of your local historical society
  • Check out archaeological sites near you
  • When you’re visiting archaeological sites, leave everything how you found it. Never take an artifact you find on the ground, or move a stone in a building.
  • Support science and science funding for institutions like the National Science Foundation and National Endowment for the Humanities. Politicians especially like to target archaeology for being fiscally useless. 

Bonus Question:  Other than your own dig, what is your favorite archaeological site? 
One of my favorite sites not too far from central Michigan is Cahokia, in western Illinois. Cahokia is a UNESCO World Heritage Site and represents one of the largest, most complex societies in what’s currently the United States. We’ve been doing research at Cahokia for such a long time, but there are still big mysteries. Maybe you can help solve them!

Thanks Kristin!

I completely agree about Cahokia.  Shara and I visited the site in 2016.  It was one of the most amazing places that we have ever been, especially when you consider that more than one hundred mounds on the site constructed entirely by human labor.  In addition to the mounds there is a world class museum displaying some of the archaeological finds from the site. 
Mounds at Cahokia

Cahokia is about eight hours from mid-Michigan by car.  We visited during a week-long vacation, but it is totally within range for an extended weekend trip. 

Wednesday, October 17, 2018

"The study of things high up"

Happy Earth Science Week 2018!

You might remember that meteorology is one of the four earth science disciplines.  Meteorology is a science that deals with the study of atmosphere and how processes in the atmosphere affect weather and climate (long term weather patterns).  The word meteorology comes from the Greek words meteĊron meaning roughly "thing high up" and logia meaning "study or discussion of".  

One of my favorite "things high up" is clouds - so today I am going to share a ten of my favorite cloud images from the past year.

Get your Earth Science Week Geek On!

Happy Earth Science Week 2018!

Earth Science Week is an annual week-long celebration of everything earth science.  This celebration is sponsored the American Geosciences Institute.

When you think of exciting earth science locations, Michigan doesn't immediately spring to mind.  That doesn't mean that there isn't a lot to see.

Here are five of my favorite locations in Michigan.

Sleeping Bear Dunes National Lakeshore

Located in the northwest part of the Lower Peninsula, Sleeping Bear Dunes National Lakeshore is probably the best place to see sand dunes anywhere along the Great Lakes shorelines.  These dunes have built up since the end of the last glacial maximum (ice age) and now soar hundreds of feet above the surface of Lake Michigan.  The dunes are not the only attraction - Sleeping Bear dunes also has dozens of miles of hiking trails, some of the best spring wildflowers in the state, and two islands to explore (North and South Manitou).

Pictured Rocks National Lakeshore

If Sleeping Bear Dunes is all about sand, Pictured Rocks National Lakeshore is all about sandstone.  The geologic formation of Pictured Rocks dates back more than 500 million years.  While you can enjoy the Pictured Rocks from land, they are best seen from the water.  Located along the shoreline of Lake Superior near Munising, MI Pictured Rocks National Lakeshore is too far away from Mid-Michigan for a day trip, but can easily be visited during a long weekend.  Not only are there giant sandstone cliffs, but the Lakeshore is home to several spectacular waterfalls and the largest dunes on Lake Superior (Grand Sable Dunes).

Lake of the Clouds, Porcupine Mountains Wilderness State Park

Porcupine Mountains State Park is located near the west end of the Upper Peninsula along the shore of Lake Superior.  The valley that holds Lake of the Clouds was carved out by glaciers from rock dating as much as 1.1 billion years old.  This rock can best be seen from the Lake of the Clouds overlook on the Carp River Escarpment.

As a bonus, this area is home to several fault lines - places where plates of the earth's crust contact each other.  One of these faults can be seen at nearby Bonanza Falls, where the Big Iron river crosses over a tilted layer of Nonesuch Shale.  Bonanza falls is located just east of the park boundary near Silver City, MI.

If you visit the Porcupine Mountains take the time to drive up the nearby Keweenaw Peninsula to visit the A.E. Seaman Mineral Museum at Michigan Technological University.  It's a geology nerd destination in its own right.

Muskallonge Lake State Park

To me Muskallonge Lake State Park is the best place in Michigan to pick up rocks.  The park is located in the eastern Upper Peninsula, tucked between the shore or Lake Superior and inland Muskallonge Lake.  The shoreline of Lake Superior is a rock beach - with new rocks being constantly driven up by waves from the lake this is a rockhunters dream.  I find it impossible to leave with out pockets full of rocks.  Everyone is looking for agates, but some of the igneous rocks are just as beautiful!

As a bonus, Muskallonge Lake has some of the best stargazing I have ever experienced.  We lay on a picnic table watching the stars at 2:00AM for nearly an hour during our last visit to the park.

Bundy Hill Preserve

I hate to say it, but Mid-Michigan is not the best location for geology nerds.  Our rock formations are buried under hundreds of feet of glacial till.  If you can't beat the glacial deposits, you might as well enjoy them!  Bundy Hill is the highest point in Isabella County.  At 500 feet higher than the nearby town of Mt. Pleasant, Bundy Hill is a moraine, formed where two glacial lobes came together, piling sand and rock between them.  Owned by the Chippewa Watershed Conservancy, Bundy Hill is accessible to the public and has two miles of brand new hiking trails.  If you go, make sure to take a picture of the summit marker and search for the large boulders (glacial erratics) that dot the site.  One of these boulders, located near the summit is nearly 40 feet around!

Monday, October 15, 2018

Geology rocks!

Happy Earth Science Week 2018!

Earth Science Week is an annual week-long celebration of everything earth science.  This celebration is sponsored the American Geosciences Institute.

Of the four earth science disciplines (geology, meteorology, oceanography, and astronomy), geology is my favorite.  Geology is the study of the earth itself, the substances that make up the earth, the processes that shape the earth, and how those processes and substances have changed over time (and continue to change today). 

Everywhere we go we see geologic processes and materials, especially rocks in their various states.  It is easy to overlook them because they are so commonplace, but when you understand the processes that shape them and the history behind them rocks are much easier to appreciate. 

It all starts with knowing how rocks form.

Rocks are divided into three main types based on how they form: igneous, sedimentary, or metamorphic.

Igneous rocks form when molten magma or lava cool down and become solid.  Magma and lava are both the same thing – rock that is so hot it has melted.  The only difference between magma and lava is their location.  Magma is found below the surface of the earth.  Lava is found above the surface.

When magma and lava cool down, the molten minerals that are contained within crystallize.  We can tell where an igneous rock formed by looking at the size of the crystals.  Igneous rocks that form below the surface cool slowly and form large crystals.  These rocks are known as intrusive igneous rocks or plutonic rocks.  Igneous rocks that form above the surface cool down quickly and the crystals are smaller because they have less time to form.  These are known as extrusive igneous rocks.

Pegmatite (an intrusive igneous rock) has very large visible crystals.

Devil's Tower is made of intrusive igneous rock - the softer rock surrounding it has eroded away over time.

Sedimentary rocks are formed from smaller particles of rocks and/or minerals that have been fused together by pressure and the crystallization of dissolved minerals.  Large rocks of all types break down over time.  Natural factors such as wind, water, and temperature change cause the surface of rocks to weaken.  This process is known as weathering.  If the surface of a rock breaks down enough, wind and water may remove this weathered material from the surface of the parent rock and deposit it in another location.  This process of removal and deposition is known as erosion.  The particles that are carried away and deposited are known as sediment.

Given enough time these sediments can build up in thick layers.  The weight of upper layers of sediment can cause particles in the lower layers to fuse together.  Sometimes dissolved minerals in the lower layers will crystallize as water is forced out by the pressure of the upper layers.  These minerals act like a cement or glue, further fusing the sediments together.  The layers of sediment can often be seen in sedimentary rocks.
Visible layers in sandstone show how this sediment was deposited over time.
The angled layers in this sandstone indicate that a current was present when the sediment was deposited.

Metamorphic rocks are rocks that have been changed by heat, pressure, or chemical processes.  The word metamorphic actually means “changed in form”.  The intense heat and pressures that are found deep within the earth can cause changes to preexisting rocks.  The minerals within a rock may partially melt and become glassy in appearance.  The crystals may rearrange themselves in reaction to external pressures.  This often results in bands or “foliations” forming within the metamorphic rock.  Metamorphic rocks can also form through a change in the chemical composition of the minerals within a preexisting rock.

Metamorphic rocks can form from any type of rock.  Igneous rocks, sedimentary rocks, and even metamorphic rocks can all change form.

Fracturing and folding in a metamorphic rock indicate that this rock faced pressure coming from the sides

Sunday, October 14, 2018

What is earth science?

Happy Earth Science Week 2018!

Sponsored by the American Geosciences Institute, Earth Science Week is a week-long celebration of everything related to the earth sciences.  In honor of Earth Science Week, I will be posting something relevant to earth science every single day.

You might be wondering, what is earth science?

Earth science is simply the study of the earth.  It is generally broken down into four disciplines: geology, meteorology, oceanography, and astronomy.

Geology is the study of the earth itself, the substances that make up the earth, the processes that shape it, and how those processes and materials have changes (or stayed the same) over time.  Of the four earth science disciplines, this one is my favorite (but don't tell the other- they get jealous). 

Badlands NP, South Dakota

Meteorology is the study of the earth's atmosphere and how processes and patterns in the atmosphere affect the earth's weather and climate.
Isabella County, Michigan

Oceanography is the study of the earth's oceans (and seas) including their patterns, composition, currents, and the organisms that reside in them.

Acadia NP, Maine

Lastly, astronomy is the study of the universe and earth's place in it.  Objects and forces outside the earth's atmosphere can and do have a profound impact on this planet.  This includes everyday actions such as the tides (caused by the moon's gravity) and solar storms to less common events such as asteroid strikes.

Photographed from Alma, Michigan

Although earth science is divided into these four disciplines, they are completely intertwined and cannot not readily be separated.  Other subjects are also inseparable from the study of the earth sciences.  I have a degree in history.  History is in many ways a function of physical geography.  Geography is dependent on geology (and oceanography and meteorology).  Without understanding these larger connections, it is almost impossible to truly understand our place in the world.

Over the next week I'll be sharing an earth science post every single day.  I hope to cover some new ground that I haven't discussed before.

Tuesday, October 9, 2018

Michigan Species to Know - Downy Woodpecker (Piocides pubescens)

Here's the next Michigan species card that I promised - the Downy Woodpecker (Picoides pubescens).  This small woodpecker is a common sight around Michigan and visits bird feeders regularly. I have written several times about this species including a species profile from January 2016.

Tomorrow I will share one of the ways that I use cards such as this in the classroom.

Monday, October 8, 2018

Michigan Species to Know - Tree Swallow (Tachycineta bicolor)

Here's the next Michigan species card - the Tree Swallow (Tachycineta bicolor).  I've written extensively about this species in the past, including this species profile from 2013.  Tomorrow I will post a card for the Downy Woodpecker and then I'll share a way that i use these in the classroom.