The Rock Sea of Hickory Run: Exploring Pennsylvania's Boulder Field
Imagine standing at the edge of a landscape that looks like a giant's playground made entirely of stone. Deep within Hickory Run State Park in northeastern Pennsylvania lies an extraordinary natural wonder known simply as the Boulder Field. Stretching across a space equal to nearly one hundred football fields, this vast landscape is covered in millions of reddish-tan rocks. Visitors who walk up to its edge are often amazed by the quiet, surreal sight of a dense green forest that suddenly stops, giving way to an endless sea of stone.
How did all of these massive rocks end up in one place? The story of the Boulder Field began thousands of years ago during the last ice age. A thick sheet of ice called a glacier covered much of northern Pennsylvania. Although the edge of the glacier stopped just a few miles north of the field, it created freezing conditions in the surrounding area. Water seeped into small cracks within the bedrock. As the temperatures plunged, this trapped water froze and expanded, acting like a powerful wedge that broke the rock into huge pieces. This repeated freezing and thawing, known as frost wedging, eventually shattered the solid ground into millions of boulders.
- surreal:
- Strange or dreamlike, beyond what seems normal or real.
- glacier:
- A large, thick sheet of ice that moves slowly over land.
- bedrock:
- The solid layer of rock lying beneath soil and surface materials.
- boulders:
- Very large, worn, or rounded rocks.
- expanse:
- A wide, open, and continuous area of land.
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Preview questions from this passageShowHide
- 1Where is the Boulder Field located?
- 2How large is the Boulder Field described in the passage?
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About this informational passage for Upper Elementary
“The Rock Sea of Hickory Run: Exploring Pennsylvania's Boulder Field” is a informational reading passage about Hickory Run State Park Boulder Field, written for Upper Elementary. It takes about 2 minutes to read (367 words) and comes with an interactive quiz and a printable worksheet with comprehension questions and an answer key.