Facts by Claire-Jean Korzenewski (10)
Eratosthenes Measured Earth’s Circumference—Centuries Before Columbus Sailed
Eratosthenes (c. 276 – 194 BC) was born more than 2200 years ago in the Greek city of Cyrene, now a city in…
Finding Ice In The Rocks--Evidence Of Earth's Ice Ages
In the late 1700s, geologists began trying to determine how huge boulders of granite weighing several tons…
How Do We Predict The Climate--100,000 Years Ago?
Since the only ice age that occurred during human existence ended 10,000 to 12,000 years ago, how can we know…
Igneous Rocks, Born of Fire
Rocks are naturally occurring solid mixtures of substances primarily made of minerals. There are three kinds…
Metamorphic Rock
There are three rock types on earth, named according to how the rock is formed. Igneous rock forms as it cools…
Rock, Mineral, Crystal, or Gemstone?
Rocks and minerals are all around us and used every day, perhaps without us even being aware of them. Besides…
Sedimentary Rock
Sedimentary rock is one of three rock types on earth. Rock types are classified according to how the rock is…
Silent Earthquakes
Try this demonstration of earthquake movement. Shape modeling clay into two blocks or get two firm sponge…
Weathering, Erosion, and Deposition
Weathering, erosion, and deposition are processes continually at work on or near earth's surface. Over time,…
What Causes Ice Ages....Or Global Warming?
We know from the rock record and cores taken from polar ice caps that periods of global cooling (ice ages, or…