Rock is a hard, solid material that makes up part of Earth. In many places, the rock is covered by a layer of soil in which plants or trees may grow. Soil is made up of tiny bits of rocks mixed with materials from dead plants and animals. Rock also lies under the oceans. Most rocks are made up of one or more minerals.
Explanation
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Igneous rocks start out as melted rock, called magma, deep within Earth. Earthquakes and other movements of Earth's crust sometimes force the magma to the surface. Igneous rocks form when the magma cools and hardens.
The three main kinds of rocks are igneous > rocks, sedimentary > rocks, and metamorphic > rocks.
Chalk is a soft, white rock. It formed as mud on the bottom of an ocean that has disappeared. Chalk is a rock called limestone. Unlike other kinds of limestone, chalk did not harden as it formed.
Metals such as aluminum, iron, lead, and tin come from rocks called ores >. Ore may lie close to Earth's surface or deep underground.
Rocks also provide information about Earth and its history. Scientists called geologists > learn the history of Earth by studying rocks. They figure out where to find oil by studying rock layers
Uluru is a huge rock shaped something like a loaf of bread. It is the world's largest single stone. It rises 1,100 feet (335 meters) above a desert in the middle of Australia. Uluru measures 5 miles (8 kilometers) all the way around. It is made of a type of rock called red sandstone.
Quarrying is a way of mining a substance that lies at Earth's surface. This method is used to dig out large blocks of stone called dimension stone.
Plymouth Rock is a granite rock with the date 1620 carved on it. A group of Pilgrim explorers came ashore from their ship, the Mayflower, in December 1620. A story tells that they stepped onto the rock when they landed.
Zuma Rock is a huge rock formation in central Nigeria. It is northwest of Abuja, Nigeria’s capital. Zuma Rock rises sharply 2,379 feet (725 meters) above the surrounding savanna (grasslands with scattered trees). Zuma Rock is a symbol of Nigeria and a popular tourist destination.
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