Volcanism
Where are most volcanoes on Earth located?
Where are most volcanoes on Earth located?
Who first proposed the idea that continents move?
Alfred Wegener
Which is the oldest era in Earth’s history?
Precambrian
What was the name of the supercontinent that existed 200 million years ago?
Pangaea
Name one of the three main forces of erosion.
Wind, water, or glaciers
What is the difference between dormant and extinct volcanoes?
Dormant = inactive but may erupt again; Extinct = will never erupt again
What type of plate movement creates new crust?
Divergent plates (constructive boundaries)
Which era is known as the “Age of Dinosaurs”?
Mesozoic
At what speed do continents move each year?
2.5 to 5 cm per year
What type of valley shape is formed by glaciers?
U-shaped valleys
What type of volcano is Mauna Loa in Hawaii?
Shield volcano
Which mountain range was formed by convergent plates colliding?
The Himalayas
What happened during the Permian mass extinction?
About 96% of marine life and 70% of land species disappeared
Which region’s elevation was raised by continental drift and now lies 900–1500
Mongolian Plateau
What kind of soil, deposited by wind after the Ice Age, is very fertile?
Loess
What volcanic feature forms when a crater collapses after a huge eruption?
A caldera
What is the name of the fault in California where the Pacific and North American plates slide past each other?
San Andreas Fault
Which gas did Precambrian organisms add to Earth’s atmosphere?
Oxygen (from photosynthesis)
What process explains how mountains form when plates converge?
Orogeny
What is the process of sediment being carried away by rivers, glaciers, or wind, and then deposited elsewhere?
Sedimentation
Name two benefits volcanoes bring to humans.
Fertile soils, geothermal energy, hot springs, creation of new land, atmosphere formation, tourism
Why do the youngest oceanic rocks form near mid-ocean ridges while the oldest are found near continental margins?
Because new crust is continuously created at divergent boundaries (mid-ocean ridges) by rising magma, while older crust is pushed outward toward the continents before being subducted.
hat geological evidence links the end of the Mesozoic era to the extinction of the dinosaurs, and which rare element is found in those sediments?
Sediment layers from ~66 million years ago show high concentrations of iridium, likely deposited by a meteorite impact, which contributed to the mass extinction at the end of the Mesozoic.
Which plates are responsible for frequent earthquakes in Japan?
Pacific, Philippine, Australian, and Eurasian/North American plates
What is the largest river delta in the world?
The Ganges Delta