The earth's mantle is a layer of rock beneath the crust that is 1800 miles thick. The deepest part of the mantle is hotter than the area near the Moho so that the deepest rocks are molten. Below the mantle is the earth's core: the molten outer core which is 1400 miles thick and t...
"The surface of the earth is made of tectonic plates, which are about 100 kilometers thick, they move around together. So when they collide or move apart, they form earthquakes as the pressure gathers," explains seismologist Carlo Doglioni, President of Italy's National Institute...
The troposphere, the bottommost layer of Earth’s atmosphere, is the densest of the five atmospheric layers and extends from ground level up to about 10 kilometers in altitude. This is the layer where humans live and breathe, as it contains the air we depend on for survival. The tropospher...
Superlatives like "the world's biggest" and "the world's first" are almost as ubiquitous as the skyscrapers and mega-projects that have come to define this city-state on the Arabian Peninsula, home to the tallest building and the busiest international airport on Earth. With time, ...
Theprimary sectorinvolves companies that participate in the extraction and harvesting of natural products from the Earth. Primary sector companies are typically engaged in economic activity that utilizes the Earth's natural resources, which are sold to consumers or commercial businesses. ...
the confused owner of a cone five hundred feet high. Within two years it had topped out at almost fourteen hundred feet and was more than half a mile across. Altogether there are some ten thousand of these volcanoes on Earth, all but a few hundred of them extinct. There is, however, ...
Crude oil is a raw natural resource that is extracted from the earth and refined into products such as gasoline, jet fuel, and other petroleum products. It is composed of hydrocarbon deposits and other organic materials that were formed from the remains of animals and plants that lived millions...
The speed of growth depends on the type of bamboo, the earth and the season. Normal bamboo grows 3—10 cm a day. It usually grows in tropical (热带的) areas. 3 Bamboo plants are found in Asia, Australia, parts of Africa, and South America. One of the world’s oldest building ...
the world. We could not breathe without air. Airplanes could not fly without air. They need air to lift their wings. Airplanes cannot fly very high because as they go higher the air gets thinner. If we go far enough away from the earth, we find there is no air. What is the sky?
A warmer planet doesn’t just raise temperatures. From wildfires to floods, here's how the climate is changing.