Posted on April 16, 2022 (Updated on July 9, 2025)
What are animal fossils?
Regional SpecificsFossils are the preserved remains of plants or animals that are at least 10,000 years old. Animal fossils come in two main types: body fossils and trace fossils. Some animal fossils form through the process of perminerialization. What is the most common animal fossil? snail Turritella By far the most common fossil, based on the
Posted on April 16, 2022 (Updated on July 9, 2025)
Why are some minerals considered gems?
Regional SpecificsA gemstone is usually a mineral, but it is one that has formed crystals and then been cut and polished professionally to be made into a piece of jewelry. The study of gemstones is called gemology. Why are some minerals referred to as a gem? Many minerals form beautiful crystals, but the most prized of
Posted on April 16, 2022 (Updated on July 9, 2025)
What powers Earth’s climate system and which of Earth’s spheres are involved in this system?
Regional SpecificsThe earth is a vast, complex system powered by two sources of energy: an internal source (the decay of radioactive elements in the geosphere, which generates geothermal heat) and an external source (the solar radiation received from the Sun); the vast majority of the energy in the earth system comes from the Sun. What powers
Posted on April 16, 2022 (Updated on July 9, 2025)
When and where do we have volcanoes in the United States?
Regional SpecificsMost of these are located in Alaska, where eruptions occur virtually every year. Others are located throughout the west and in Hawaii (see our Volcano Activity Map for their locations). Kilauea volcano in Hawaii is one of the most active volcanoes on Earth. It has been erupting almost continuously since 1983.” Where are the volcanoes
Posted on April 16, 2022 (Updated on July 9, 2025)
Is the Hayward Fault active?
Regional SpecificsCreep on the Hayward Fault The Hayward Fault is actively moving, year-by-year. This characteristic is unlike that of other earthquake faults such as the San Andreas Fault, which is “locked” between major earthquakes. Is the Hayward Fault overdue? “We know that the last major earthquake on the Hayward Fault occurred in 1868 — 153 years
Posted on April 16, 2022 (Updated on July 9, 2025)
How are continental glaciers and valley glaciers different?
Regional SpecificsValley glaciers can flow in all directions as they move, while continental glaciers move down slopes already cut by rivers. Valley glaciers cover much of a continent, while continental glaciers cover a small area of mountains. Continental glaciers are long and narrow, while valley glaciers are wider in size. What is one main difference between