North Shore Camping - Day 4

The title says 'North Shore Camping', but Day 4 found us almost sixty miles away from Lake Superior at the Trail's End campground at the end of the Gunflint Trail.  The plan for the morning was to accompany a group of Earth Science teachers and several geology professors on a couple of hikes to sites of geologic importance in the area.  The group of teachers were part of TIMES XIV, the TIMES Project is an intensive two-week long class teaching inquiry-based teaching methods and focusing them on Minnesota Earth Science.  As a past participant of TIMES (summer of 2009) and a member of the Minnesota Earth Science Teachers Association's Board of Directors, we were invited to go along on the days hikes.  My job would be to talk Earth Science with the teachers and get to know what they do in their classrooms, while giving them examples of what I do differently as a result of the TIMES Project.  Kieran and Luke's job for the day, just be themselves.

We met the group in the morning at the Magnetic Rock trailhead, the same place that we had hiked the day before, though we would not be repeating the entire hike this day.  The focus of the day were features found around the 1,878 million year old Gunflint Iron Formation.  A iron mine opened near here in the late 1800s, but failed rather quickly because the Mesabi Iron Range (located to the south) was already in operation and a financial panic scared investors in 1893.

We hiked approximately half way to Magnetic Rock to view stromatolites that are found along the trail.  Stromatolites are nearly circular algal mounds that can be several feet in diameter.  While alive, cyanobacteria (the living organism of the stromatolite) grow upward from the seafloor by trapping sediment on a sticky mat.  These organisms obtain energy by using the process of photosynthesis, essentially using carbon dioxide and releasing oxygen as a waste product.  Stromatolites are remarkable because they are the reason that we have the iron deposits around the world, before this period in Earth's history, the level of atmospheric oxygen was very low which allowed soluble iron to build in the world's oceans.  As the stromatolites began to release oxygen as a waste product, the iron in the world's oceans basically rusted (or precipitated) out of solution and was deposited on the ocean floor.  Stromatolites of this age are found around the world near most of the world's major iron formations.

The stromatolites are outlined in the pictures below.  Stromatolites are not unique to just this time period in Earth's history, they are found in many sedimentary rock sequences.  Much younger Ordovincian rocks of Southeastern Minnesota also have great examples of stromatolites.  They can even be found today in hypersaline waters, where predators are scarce, the best example being Shark Bay in Australia.

The next stop for the day was a short drive and short hike away that a catastrophic few hours in Earth's past.  Approximately 1,850 million years ago, a meteorite struck near Sudbury, Ontario, almost 450 miles away from Minnesota.  It is the second largest impact structure found and very few are older than this impact.  The outcrops showing evidence of the impact were found because a forest fire raged through the area in 2007 and removed most of the overlying vegetation, making it much easier to see the underlying rocks.

Essentially, the greater than 10 magnitude earthquakes fractured the iron formation and resulting tsunami would have re-worked or re-arranged the iron formation.  Near the base of the impact layer, angular fragments meters in length of the iron formation are cemented together in a green matrix.  Near the top of the formation, the size of the iron formation fragments are much smaller.  Iron ceased to be deposited worldwide after the impact.  For a much more detailed read on the formation of the impact layer and a history of the impact layer itself, read the document published by the Minnesota Geological Survey.

Many of the teachers we were accompanying were amazed that two boys, like Kieran and Luke, could go through some of these hikes.  A few were even surprised that they could camp in locations like these, this isn't a state park, there is no cell phone reception or any technology, and very few people.  Both boys did a great job doing there own thing, while dad got a few hours of adult inte
raction (a very rare thing for a week-long camping trip).  The boys even added to their rock collection, which of course, dad had to carry.

The picture below shows Kieran sitting on the burnt remains of a tree, just above the last outcrop that we would visit with the TIMES group, though they would continue on for at least one more stop before returning to the Twin Cities that evening.  It is located just a short hike down National Forest Service Road 1347 from the previous stop.

At this particular outcrop, you are able to stand near the uppermost portion of the Sudbury Impact Layer.  Deposited here are accretionary lapilli, essentially ash pellets that were thrown away from the impact site.  Using very high powered microscopes, shocked quartz (which is only found at impact sites) can be found in these centimeter pellets, commonly called ejecta, and the surrounding matix.  Look for the small circle structures in the pictures below.

After leaving the TIMES XIV group around 2:00 pm, we had a little bit of time to return to the campsite and relax.  Of course the boys have a different way of relaxing than I do, we had to explore the campsite.  Because of setting up the camp and cooking dinner under the threat of a thunderstorm the night before (though we only had thunder, no rain), we had not wandered the area properly.  Of course the boys through some rocks into the lake.

We later visited the Chik-Wauk Museum which Kieran really enjoyed the scavenger hunt that was available for kids.  The museum tells the history of the Gunflint Trail - biological, geological and human.  The ladies at the desk also gave us the directions to a sand swimming beach nearby, though when we got to the location given at nearly 5:00 pm it turned out to be a swamp.  The directions given were wrong or we went to the wrong location, either way the boys chose not to do any swimming.

On the drive back to the campsite from the swamp (a ten minute drive), the experiences of the last four days caught up with the boys as they fell asleep.  When we got back to camp, I carried them to their camp chairs because I didn't want them sleeping in the high temperatures of the van.  After a few minutes of sitting aimlessly in their chairs, I asked if they would like to lay on their sleeping bags in the tent, both immediately said yes (keep in mind this was about 5:30 pm).  Kieran woke up at 8:30 pm hungry, we made some hot dogs quick and he was back in the tent by 8:50.  Luke slept through the night until he woke up fairly hungry at 6:00 am.  I would say that they were exhausted...

This would be our last night at the Trail's End campground before we left for the North Shore again.  The campground is interesting because the forest fire burnt some areas of the campground to the ground and left others untouched.  The difference is extremely visible when walking around the area.  The areas that were completely burned have large outcrops of a whitish granite, the 2,689 million year old Saganaga Tonalite, where the areas that were not burned have basically an old growth forest ecosystem.

Day 5 would take us back to Lake Superior with several stops before reaching Tettegouche State Park.

To be continued...

North Shore Camping - Day 3

On Wednesday, June 27th, the boys and I packed up our campsite at Gooseberry Falls State Park.  We've stayed in the same campsite at this park each of the past three years, and will probably do so again next summer (the boys are already planning on how to catch the tadpoles more easily).
The first stop of the day was a quick one, we stopped briefly at the overlook of Split Rock Lighthouse.  Construction in the area is finally finished, they've been working on Hwy 61 here for the past few summers.  Basically, they carved a new road bypass out of the bedrock, so now that overlook is not directly next to the highway its much safer.

After driving about an hour north, we made a brief stop at Cascade River State Park (approximately 10 miles south of Grand Marais) to get the boys a chance to stretch their legs and see another waterfall.  Kieran and I had camped here two summers ago, but it was completely new to Luke.  On the way to the series of waterfalls here, we stopped to hug a tree (the boys tend to do that).  Actually, I've got a picture of Kieran hugging this same tree when he was four years old, it's a big, old white pine.

After about a 1/2 mile hike uphill (including 74 steps, counted by Kieran), we came to the Cascades.  Still flowing fairly well from the prior week's rainfall, the Cascades are a series of waterfalls as the river it attempting to reach the level of Lake Superior.  As are many locations on the North Shore, it's located along the Superior Hiking Trail and is popular stop, we passed numerous people.

About halfway from Cascade River State Park and Grand Marais, we made a stop at a roadcut were we tend to stop.  It's at Good Thunder Bay (http://earthscienceguy.posterous.com/minnesota-geology-monday-good-thunder-bay).  The entire North Shore is made of numerous lava flows of the 1,100 million year old Mid-Continent Rift System.  In between lava flows, erosional processes broke the lava flows down and formed sedimentary rocks, like sandstones.  This location shows one of the most accessible interflow sedimentary structures on the North Shore, the red rock underneath is a sedimentary sandstone, while the black rock on top is basalt.  The basalt is younger than the sandstone, because it flowed as lava onto the top of the sandstone.  A great gigapan of the site is found at (if you've never seen a giga pan, check it out):  http://www.gigapan.org/gigapans/86878.

They boys like the previous stop because they know that they are close to the rest area at Cut Face Creek.  It's a great rest stop, located right on Lake Superior where the boys get to, throw some more rocks.

Cut Face Creek flows into the lake at this stop and Kieran has made it a priority for the last four summers to dam this creek up.  He's had Luke's assistance for the last two summers, basically, they spend an hour or more placing as many large rocks in the way of the creek.  They have not been successful yet.  It's another stop where both of the boys bring a large n
umber of basalt, rhyolite and sandstone rocks home with them.

After stopping for a pizza lunch at Sven & Ole's (http://www.svenandoles.com/) in Grand Marias and also checking e-mails, twitter, the internet and sending a few texts (once leaving the city, this wouldn't be possible), we made the turn onto Cook County Highway 12, the Gunflint Trail.  Our destination was the Trail's End campground, 57 miles away.

About ten miles before the end of the trail, we made a stop at the Magnetic Rock trailhead.  The boys did not believe me that there are rocks that magnets are attracted to, Magnetic Rock is one of those rocks.  Actually, most of the rocks along the trail will attract magnets.  Magnetic Rock is a large piece of the Gunflint Iron Formation that has been tipped on end as a result of late Wisconsin glaciation ( http://earthscienceguy.posterous.com/minnesota-geology-monday-magnetic-rock).

A forest fire in 2007 removed most of the vegetation in the area and you see lots of evidence of burnt trees (some still standing), but the area is growing back quickly.  Kieran and Luke got good at looking for 'blue tape', knowing that if they found it, we were on the right trail.  The trail to Magnetic Rock is about 1 1/4 miles to the rock, mostly uphill.  On some areas you are hiking on exposed Gunflint Iron Formation and in others you are surrounded with shrubs and saplings.  There are lots of random boulders/rocks and tree roots to avoid while hiking.  This was a hard hike for Luke's little legs, but he did great.

Kieran's first task upon reaching Magnetic Rock was to see if it's actually Magnetic.  He is pointing to a yellow magnet brought along just for this occasion.  Kieran tried over and over and finally realized that there are distinct areas in the rock that are magnetic, these areas are comprised primarily of the mineral magnetite.

We spent about thirty minutes at Magnetic Rock, Luke spent most of the time sitting down eating snacks and drinking some of the juice boxes/water that I brought along.

Kieran tired of the resting quickly and decided he needed to climb some rocks.  He really wanted to try to climb Magnetic Rock, but I convinced him to climb some of the smaller pieces that had weathered off of the larger rock.  When looking at the piece he was climbing on, Kieran even said that it's a piece of the larger rock and he pointed out where it came from on Magnetic Rock.  He's beginning to 'get it'.

After we began our hike back, Kieran suddenly had to use the restroom and was told to go find a tree.  When he saw the camera coming out, he was initially apprehensive, but finally said "go ahead, here's my underwear."

What's nice about this hike, besides the fact that we never saw another person and were probably surrounded by numerous bears and wolves, was the amount of wild blueberries, raspberries and strawberries found along the trail.  Actually, the number of raspberries and strawberries was lower than years before (my assumption is the increasing height of the vegetation is a detriment to them), but the blueberries were common on exposed areas of the iron formation.  The pictures below try to show the elevation change you make on the trail, they are taken from a ridge and far in the background is the Gunflint Trail (County Road 12) near the trailhead.

On the hike back, we took many more rest stops than we did on the hike in, it was a difficult hike for the boys (especially Luke).  It was hard for me carrying all of the snacks and juice/water.  We even hauled in a magnet, compass (to see the rock's effect on it) and a first aid kit (you never know).

When we made it back to the car, we drove the last 10 miles to our campsite so we could set up camp and cook dinner.  We went to bed early that night.....we were tired.

The next day we met up with a group of Minnesota science teachers for about six hours for a couple of more hikes, but that's for later.

To be continued....

North Shore Camping - Day 2

Tuesday started with a quick breakfast before the boys had a plan.  As soon as they had finished breakfast, they wanted to go for a hike, which of course was fine.  They led the way....

They led us straight to the picnic lava flows down by Lake Superior.  Apparently they had the idea that they needed to look for something....

Of course, the something that they wanted to look for was tadpoles.....and they had no problem finding them and catching them....

I spent the hour and a half looking around at features you find on the picnic lava flows, like how the lichen is growing or buildings built by the CCC in the 1930s.

After we had returned to camp, it was time to go and view the three main waterfalls at Gooseberry Falls State Park.  The pictures below show the Upper Falls, located just north of the Hwy 61 bridge.

Next we had to stop and get as close to the Middle Falls as we could, we actually got closer than the picture shows but I needed to hold onto the boys as opposed to the camera.

From the Middle Falls, the boys and I continued on a rather long hike that would take us downstream, eventually cross the river and bring us back on the opposite side of the river.  Signs of the recent flooding were everywhere, with most vegetation being pushed down to the ground and no longer being upright.

Large trees were also laying as they were thrown, the amount of water needed to move some of these trees would've been impressive.....at this point we were also able to look straight up river to see the Middle and Lower Falls.

On the Eastern side of the Gooseberry River, the trail takes you to some impressive overlooks, of course these overlooks are at quite a height above the river level.

It's also interested to get a view of the Middle Falls from a different perspective, we're not sure how many people take the time to get to this side of the river.

Before returning to the visitor's center, the trail takes you underneath the Hwy. 61 bridge by a walkway and gives you the opportunity to view the Upper Falls from a different angle.  Pops has always claimed that in his more 'reckless' days he traversed the bridge via the beams located underneath the structure....not really sure if it's true or not...

After viewing the falls, we took a quick trip up the road to the Split Rock Lighthouse.  Luke had never been to the lighthouse, Kieran had a few years earlier.

We had to take the stairs to the top of the lighthouse, the stairs are tight and Luke did not especially enjoy them (particularly the way down).  But it is an interesting view from out the windows in the lighthouse.

After leaving the lighthouse, Kieran really wanted to go down to the lake level and they apparently found a tree to hug along the way (it wasn't the first or the last tree they would hug).

Getting to the lake level involves a large amount of stairs, the trip down is not bad at all, then you remember that the vehicle is parked at the top and you'll be walking them again...

What did the boys want to do at the bottom?  They didn't really care for the view, they wanted to throw rocks into the lake, again....

Of course before beginning the hike up the stairs to the van, they (and I) wanted a quick rest break.

After leaving the museum, both boys were immediately drawn to the anchor of a ship that had crashed over 100 years earlier, they had ignored the anchor on the way in...

After leaving Split Rock, we went to the beach at Beaver Bay (apparently one of the best places to find an agate on the north shore).  All the boys wanted to do of course is.....throw rocks.....

I was looking for an anorthosite inclusion in the surrounding basalt.  The greenish anorthosite crystalized at depth (20-25 km) before riding to the surface with later lava flows.

After dinner that evening, we took another hike to view the falls, but this time it was from a straight-on viewpoint.  It was about a mile hike before the trail was closed because of being washed out from the recent floods, but it gives another view of Gooseberry Falls.

After returning to camp, exhausted, it was time for bed.  It was our last night at Gooseberry Falls State Park.

The next day, we left for Trail's End of the Gunflint Trail.  Before we made camp the next day, we hiked to Magnetic Rock just off the Gunflint (meaning a 1 mile hike, uphill, one way)....

Too be continued....