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middle school science
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Human Dependence on Natural Resources I Can: Explain and describe how natural resources are unevenly distributed as a result of past geologic events.
Human Impact on Environment Planet Song Golden Buzzer
What are geological events? What examples can you name? brainstorm
The Distribution of Earth’s Resources The Earth has many natural resources; however, these resources are becoming more prized as the years pass by. This is because people use too much of some resources. Some people have recently decided that they must protect Earth’s natural resources. They want to make sure resources will be available in the future. Many scientists are now looking for new ways to save these resources. They also want to take better care of our planet. Some of the natural resources that we use are renewable. Trees, air, and water are renewable resources. These resources can be replaced by nature in a short period of time. Other resources produced by Earth are nonrenewable. Nonrenewable resources are natural resources that cannot be replaced once they have been used. These resources include minerals and fossil fuels such as oil, coal, and natural gas. Let’s take a look at two different areas of the United States where nonrenewable resources can be found.
The Distribution of Earth’s Resources The High Plains aquifer is one of the largest groundwater supplies in the world. It is found under the entire state of Nebraska and parts of Colorado, Kansas, New Mexico, Oklahoma, South Dakota, and Wyoming. People in these states have been taking water from the aquifer for many years. The High Plains aquifer developed about 65 million years ago. A great tectonic plate event occurred at that time. The plates pushed together and formed what we know today as the Rocky Mountains. As the mountains began pushing upward, wind and water began weathering the peaks. Rivers and streams carried the sediments eatsward. The water and sediment slowly built up to form the High Plains aquifer. The High Plains aquifer is a few feet deep at some places. At other places it is up to 1,000 feet deep. In some areas, the aquifer is mostly gravel. That allows room for water to sit in between the rocks. In other areas, the aquifer’s bottom is tightly packed with sand. The sand holds less water than the gravel. Since the 1940’s, 88 trillion gallons of water have been extracted from the High Plains aquifer. The water is mainly used on farms that grow grains to feed millions of people. Water does make its way back into the aquifer; however, people are pumping it out faster than it will fill back up. It would take nearly 6,000 years of rainfall to replace what has been taken out of the aquifer.
The Distribution of Earth’s Resources Hundreds of oil wells have been drilled into the ground below the Gulf of Mexico. Oil and other fossil fuels formed more than 290 million years ago. Plants that lived millions of years ago used energy from the Sun to produce their own food just like plant do today. Some of the Sun’s energy was stored in the plants as chemical energy. Animals that ate the plants stored that energy in their cells. When these early plants and animals died, not all of the bodies decompose. Some settle to the bottom of the swamp, sea or ocean where they lived. Layers of sandy sediments piled up on top of the remains. More dead organisms and sediments built up into more layers. Over millions of years, the layers of sediment were pressed and cemented together to form solid rock. The remains of the dead organisms were trapped between the layers of rocks. Heat and pressure gradually changed the remains into fossil fuels-coal, oil and natural gas. Coal is burned to produce heat and electricity. It formed in swamps from decaying plant matter called peat. Oil and natural gas formed from early plants and animals that died and fell to the bottom of the seas and oceans. Natural gas is used to heat our homes and cook our food. Oil is mainly used in transportation. The Gulf of Mexico is a good spot for finding these fossil fuels, especially natural gas and oil. However, care must be taken when finding and removing these resources from the ocean floor. If just one mistake is made, the fossil fuels can be wasted and harm fish, birds and people.
Two of my favorite video clips are linked below. The videos are eye opening for sure. NASA | A Year in the Life of Earth's CO2 World Population
Human Dependence on Natural Resources I Can: Explain and describe how natural resources are unevenly distributed as a result of past geologic events.
Directions: Answer the questions below using the map on the right.
Fresh Water Access & Lakes Directions: Read the paragraphs on slides 6 & 7. The information you read will help you complete slide 8. All life on Earth depends on water, a vital natural resource. Natural resources—such as water, air, plants, wildlife, soil, and fossil fuels—are used by humans for the basic necessities of life, including food, drinking water, energy, and shelter. As a crucial resource for human life, access to freshwater has historically determined where civilizations began and thrived. Freshwater exists on Earth’s surface in lakes, rivers, and ice, as well as below the surface as groundwater. However, it is a limited resource; freshwater makes up only about three percent of all water on Earth. Although freshwater is considered a renewable resource, the use of freshwater in some regions exceeds the ability of natural processes to replenish supplies. When the demand for freshwater cannot be met, it can lead to political tension and public-health problems. Distribution issues may arise when freshwater supplies, such as lakes, cross political boundaries. They can also occur when human activities upstream on a river adversely affect communities living downstream. Those activities can include dumping pollutants into the river or diverting large amounts of water away from where the water typically flows. Text adapted from nationalgeographic.org
How are lakes formed? All lakes fill bowl-shaped depressions in the Earth’s surface, called basins. Lake basins are formed in several ways. Many lakes, especially those in the Northern Hemisphere, were formed by glaciers that covered large areas of land during the most recent ice age, about 18,000 years ago. The huge masses of ice carved out great pits and scrubbed the land as they moved slowly along. When the glaciers melted, water filled those depressions, forming lakes. Glaciers also carved deep valleys and deposited large quantities of earth, pebbles, and boulders as they melted. These materials sometimes formed dams that trapped water and created more lakes. Many lakes in North America, including the Great Lakes, were created primarily by glaciers. Some lake basins form where plate tectonics changed the Earth’s crust, making it buckle and fold or break apart. When the crust breaks, deep cracks, called faults, may form. These faults make natural basins that may fill with water from rainfall or from streams flowing in the basin. When these movements occur near the ocean, part of the ocean may be trapped by a new block of land thrust up from below the Earth’s surface. The Caspian Sea was formed this way. Lake Baikal was also formed by the movement of tectonic plates. Many lakes form as a result of volcanoes. After a volcano becomes inactive, its crater may fill with rain or melted snow. Sometimes the top of a volcano is blown off or collapses during an eruption, leaving a depression called a caldera. It, too, may fill with rainwater and become a lake. Crater Lake, in the U.S. state of Oregon, one of the deepest lakes in the world, was created when ancient Mount Mazama’s volcanic cone collapsed. Text adapted from nationalgeographic.org
Directions: Answer the questions using the map on the right and information from the previous slides. Great Lakes Crater Lake Lake Baikal Caspian Sea
