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Reading the Stories of Earth and Sky!    

Earth Science is about reading the stories written in the Earth.  Louis Agassiz, famous naturalist of the 1800s for whom a huge glacial lake in our region of Minnesota-North Dakota was named, once said "The book of nature is always open!" 

In a tribute to Agassiz, the poet Longfellow wrote
"Come, wander with me," [nature] said,
   "Into regions yet untrod;
 And read what is still unread
   In the manuscripts of God."

Try your hand at reading the basic stories of Earth and Sky--in nine adventure puzzles! (Spoiler alert! Hints are provided in this version.)

Space Spy Retirement Home

Stories in Landscapes

1) Ahhhhh.  At last, after a lifetime of surviving one deadly danger after another as Space Spy Mortimera Smith, you are ready to retire to your lovely property nestled along a luxurious hydrocarbon river on Titan, Moon of Saturn.  The construction company is ready to build your palatial estate (including a circular tower for your library, two secret rooms, and an escape tunnel built through the underlying rock).  However, they do need a decision from you about where on the property you want the house located.  You really don't want to have to worry about flooding by the river.  Also, you remember from your 8th grade Earth Science class that rivers can migrate through time, and you don't want your wonderful secret tunnels being undermined by the river anytime soon.  You examine the map of the property, showing a few key locations where the construction company has determined that bedrock is appropriate for the project.  You immediately realize that, to best meet your criteria, you want to build your dream home at

Bill's Bluff Overlook
Ned's Knob
Pike's Plain
Phil's Flat
Hobb's Hill

map of river valley, showing locations of bluffs, river, and flood plain.

Hint: Think about how a river will migrate with time, given that the water flows faster on the outside of bends. Also, consider where a house would flood during high water!

Hydrocarbon rivers on Titan

Hydrocarbon rivers on Titan, Illustration copyright (c) 2014 Ron Miller (used with permission).  You can see more of his space art at http://spaceart.photoshelter.com/gallery-collection/Stock-Space-Art/C0000tNDaWl3DLNQ


The Tale of Terri Tricerotops

Stories in the Rocks

2)  Your new Time Machine has just arrived in the mail from Amazon and you want to try it out!  Of course, the first thing you want to do is go back and see the dinosaurs!  You are standing on the grave of Terri Tricerotops, and planning to visit the spot where she took her final rest, but you want to know what kind of place it was so you can be prepared--you know, wear the proper shoes and all that.  Was it a swift river flowing down a mountainside?  A shallow swamp with standing water and lots of trees?  A wave-swept beach by the sea?  A sand dune in the desert?  A rocky landscape from which the glaciers have just recently retreated?

Your only clue is the nature of the rock that Terri's bones are in.  The rock is shale, made of tiny microscopic particles of clay and silt.  It looks something like the shale shown below.

Aha!  You know now that Terri's bones came to their final resting place in

The swift river in the mountains
The shallow swamp
The wave-swept beach
The dune desert
The glacial terrain

Shale in Hell Creek Fm North Dakota

Hint: Think about what the particle size tells you about the energy of the environment of deposition. Will small mud particle settle from a fast-flowing river?


The Dangers of the Trans-Dimensional Drive

Stories in the Rocks

3) A number of recent findings reveal that the space-faring Zarkons, who travel faster than light, have been visiting Earth for millions of years.  New intelligence from SSRU (Space Spies R-Us) suggests that the Zarkons may be thinking of taking over Earth.  In a desperate effort to understand faster-than-light travel, and have some chance of competing against a superior force, physicists are working to imitate their Space-Drive technology and understand its dangers.  Then, during an oil drilling operation in Oregon, a Zarkon ship lost millions of years ago is discovered thousands of feet beneath the ground, imbedded in igneous rock (which of course, suggests that the ship was trapped in liquid magma).  The Physicists recognize that this discovery might have a bearing on the nature of the Space Drive.  For example, did the ship, after travelling through another dimension, materialize within a magma chamber deep inside the planet (suggesting a navigational error during transdimensional travel), or did they simply fall into a lava flow at the surface of the planet and then get buried by rock layers laid down over the subsequent ages (providing no suggestion of transdimensional travel)?  They call in a ROS (Reader of Stories--you) to address the question.  Your clue is the nature of the rock in which the ship is buried, brought up to the surface (along with pieces of metal from the ship) by the drilling operation.  The rock is composed of microscopic crystals of olivine, pyroxene, and plagioclase, looking somewhat like the sample shown below (white object in image is about 0.8 cm wide).

The Ship became trapped in a magma chamber deep inside the planet--suggesting it arrived from another dimension
The Ship became trapped in lava at the Earth's surface--suggesting it may have arrived at Earth the normal way, from space

Igneous rock, with vesicles, no crystals seen

Hint: Think about what the size of crystals in the rock tells you. Did the tiny crystals, too small to see, form where the magma cooled slowly or quickly?


Escape to Noachian Mars

Stories in the Rocks

4) Earth's Sun is expanding into a Red Giant and will incinerate Earth and make Mars uninhabitable.  Since warp drive and faster-than-light travel were never invented, humanity's only hope is to escape into the past and colonize ancient Earth and Mars.  And Earth is already filled up.  You want to know something of the environment of ancient Mars, at the place and time you plan to colonize.  Pictures of a Martian pebble conglomerate collected by the Curiosity Rover in ancient times provides clues to that past environment.  After a careful examination, you conclude that when the sediments from the rock were deposited on ancient Mars, the region was
A desert with large, windblown dunes
A deep, quiet lake
A swift, mountain river
A sluggish river meandering across a broad plain

conglomerate Curiosity Rover 2002
  Image courtesy of NASA--via the Curiosity Rover, 2012

Hint: Think about what the size of particles tells you about the energy of the environment of deposition.


Colonizing Another World!

Stories in Landscapes and Rocks

5) You have just been awakened from a thousand years in deep sleep on a hibernation ship.  You have at last reached a planet ripe for colonization.  Your geologist collected age measurements from the planet before you were awakened, but was unfortunately killed before he had a chance to explain their meaning.  As expedition leader, you need to decide if it is safe to land and establish the colony (you worry about possible volcanism in the next few decades that might destroy the colony) or whether you should continue on to the next candidate planet.  The geologist reported that the rock at the surface is almost entirely volcanic although covered in some places by loose sediments.  The Rb-Sr isotopic age derived from the rock is over 100,000 years.  Impact crater-density age of the surface is less than 5000 years.  The C-14 age of organic material in the soil is even more recent, being less than 50 years old.

You determine that:
The age dates are clearly junk since they disagree, and should perhaps be ignored.
It's been over 100000 years since the volcanoes erupted-it's safe to land and colonize
It's been over 5000 years since the volcanoes erupted and it's probably safe to land and colonize
The volcanoes last erupted less than 50 years ago--it's not safe to land and colonize
The planet is not all the same age, which means it's unstable and it's not safe to land and colonize

Hint: Think about what age means and when the clocks get reset. Which one of the ages might tell you the age of volcanic eruptions?


 Lost Civilization!

Stories in Stratigraphy

6) In layers of rock exposed in a rugged badlands of Eastern Montana, metal tools and foundations of dwellings begin to weather from the bluffs along a river.  Not so unusual--until you realize that the rocks are from the age of the dinosaurs!  Was there a civilization on Earth when the dinosaurs were here?   Possibly a race of aliens?  Did they live on land or under the sea?  Was the ocean advancing or retreating at the time of their occupation?  Your clue is found in the sequence of rock layers in which the artifacts are found, shown conceptually below.

You determine that
The beings who made the tools lived under the sea during a time when the sea was retreating
The beings who made the tools lived on land during a time when the sea was retreating
The beings who made the tools lived under the sea during a time when the sea was advancing
The beings who made the tools lived on land during a time when the sea was advancing

cross-section of layers of rock. From bottom to top: limestone, shale with artifacts, beach sandstone, shale and coal, , river deposits

Hint: Read the story of change written in the layers of rock. Based on which type of rock is stratigraphically lower, how did the environment change over time, ? What was the environment like at the time the artifacts were deposited?


Mysterious Planet

Stories in Stratigraphy

7) You have been given the job of surveying planet XZPTL!b7 for colonization.  However, initial reports indicate that the planet has been colonized by other civilizations in the past, and none of them have survived!  Is there something wrong with this planet?  A danger that may not be obvious?  You need to find out more about these civilizations, for example did the two major civilizations live at the same time, and get wiped out by the same catastrophe?  Did one of the civilizations overtake and wipe out the other?  Which came first, the indigenous civilization or the space-faring one?  The survival of your colony may depend on this information.  You visit the planet and find that the story of the civilizations has been recorded in the layers of rock, which have undergone periods of tilting and erosion over the ages.  You sketch out the data in cross-sectional view, lines showing boundaries between rock layers, and wiggly lines showing the unconformities that represent periods of erosion at the surface of the planet.  Your data looks something like the picture below.

You see right away that

The spacefaring civilization came well before the indigenous one with no overlap
The two civilizations existed at the same time
The indigenous civilization existed well before the spacefaring one with no overlap
The spacefaring civilization immediately preceded a meteorite strike or terrible war, possibly causing it, or destroyed by it.
The indigenous civilization immediately preceded a meteorite strike or terrible war, possibly causing it, or destroyed by it.

cross-section with unconformities

Hint: Think about cross-cutting relationships. If an erosion surface cuts across a layer of rock, which had to occur first, the rock forming, or the rock getting eroded?


Hiding from the Empire!

Stories in the Clouds

8) Alwan Stagor is on the run from the Empire, his ship is damaged, and he needs to find a planet to land on, and soon.  But he doesn't want to land just anywhere.  He has to hide out, perhaps for months, and his best option is to land in a hemisphere going into summer rather than winter, giving him a chance to get established and figure out how to get food and find shelter before winter.   A quick survey of a couple of locations, one in each of the two hemispheres of the planet, shows cloud patterns very much like the cloud patterns shown above from Ancient Earth.  Understanding the process by which clouds form, Alwan quickly recognizes that

Location A is in autumn, going into winter--this location is to be avoided--and Location B is in spring going into summer, a possible landing site
Location A is in spring, going into summer--a possible landing site--and Location B is in autumn going into winter, a location to be avoided
Both locations are in autumn, going into winter--the planet must have a very non-circular orbit around its star--you need to look for a different planet
Both locations are in spring, going into summer-- the planet must have a very non-circular orbit around its star--either location makes a reasonable landing site

images of bodies of water, showing clouds over water in A, and clouds over land in B.

Hint: Think about how clouds form in rising air. Think about how quickly water and air change temperature as seasons change. Where and when will the air be rising?


Survivalist Soldier!

Stories in the Wind

Ship badly damaged.  Barely escaped the battle by slipping into hyperspace.  Unfortunately you had no time to plan or set coordinates.  As luck would have it, you emerge near an Earth-type planet and head for its northern hemisphere.  A quick scan by your dying instruments gives pressure readings at the surface, including isobars, precipitation conditions near where you hope to land (crash), and direction of storm propagation.  Your instruments fail on the way down and, unable to completely control your descent, you are unsure of your landing site relative to the large storm that your initial scan spotted.  After an hour on the ground, and some time to establish north by watching the movement of the sun, you realize that the wind was out of the east, blowing toward the west, when you first crashed and has now shifted to coming from the northeast.  At which location, relative to the large storm you spotted before your instruments died, have you landed?

At position A, and the storm has already passed your location.
At position B, and the storm has already missed your location
At position C, and the storm will likely miss you.
At position D, and you better batten down the hatches and hold off on that exploratory expedition.

isobar map, low pressure moving to the Northeast, storm north of low, cool and dry southeast of low, A is west of low, B to southwest, C to southeast, D to northeast

Hint: Given coriolis forces in the northern hemisphere of a planet, in what direction will winds spiral around a low pressure? What will be the wind direction at the different possible landing sites and how will the direction change with time?


Want to know more about how you can read the stories of the universe? 

Mary and Russ Colson have written a book for teachers called "Learning to Read the Earth and Sky":  available on Amazon or at the NSTA Bookstore for more information..

Russ offers a college-level self-learning course called "Earth Science Essentials" which is free online.   You can find it at http://web.mnstate.edu/colson/ESE/ESE.html.

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