Great Inland Sea Earthcache EarthCache
Great Inland Sea Earthcache
-
Difficulty:
-
-
Terrain:
-
Size: 
(not chosen)
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
This Earthcache features a scenic view of a wide, flat expanse of South Dakota plains. This area was once covered by a great Inland Sea.
The changing of global sea levels over millions of years was a major factor in determining the ancient geography of southern South Dakota. Through much of geologic time, salty warm water seas covered the interior great plains of the United States.
During the late Cretaceous Period, 65 to 80 million years ago, rising ocean levels several times produced flooding that created inland seaways. These seaways extended from the Gulf of Mexico to the Arctic Circle and divided North America into two parts.
Glacial action over the northern plains, about 12,000 to 15,000 years ago, was instrumental in forming the rolling topography of the Missouri River breaks.
No need to enter private property or cross fences to access this cache.
To complete requirements for the earthcache, please answer the following questions:
Q1: What is the elevation of ground zero?
Q2: In which direction do you look to see the best representation of the broad expanse of the sea floor?
Q3: Observe the soil conditions at GZ; is the area heavily filled, moderately filled, or lightly filled with rocky glacial moraine?
Q4: What description best describes the soil at GZ?
Optional: If you would like to do so, a picture of you or your group at GZ would be greatly appreciated.
Additional Hints
(No hints available.)
Treasures
You'll collect a digital Treasure from one of these collections when you find and log this geocache:
Loading Treasures