Plates
The landmass where all the continents were connected together.
What is Pangea?
An earthquake happens when enough of this builds up in the Earth's crust.
What is stress?
This substance found in the mantle becomes lava at the Earth's surface.
What is magma?
These form when sediment hardens into rock, preserving the shapes of organisms.
What are fossils?
The Earth's age.
What is 4.6 billion years old?
Subduction takes place here.
What are deep-ocean trenches?
S, P, and Surface waves
What are the 3 types of waves produced by an earthquake?
A type of volcanic mountain that is composed of alternating layers of lava and ash.
What is a composite volcano?
Fossils found in this layer of rock are usually the oldest.
What is the lowest layer?
Geological Time is divided into ______ which are further divided into ______ .
What are eras divided into periods?
These form long chains of mountains that rise up from the ocean floor.
What are mid-ocean ridges?
A type of stress that pulls things apart.
What is tension?
Yellowstone and the Hawaiian islands are examples of these volcanoes, caused by plate movement over time.
What are hot spot volcanoes?
Paleontologists have found many fossils of this type of animal which spread widely during the Mesozoic Era.
What are reptiles (dinosaurs)?
The first era of Earth's History. It accounts for 88% of time.
What is the Precambrian Era?
This causes the plates to push apart in the ocean.
What is sea-floor spreading?
The transform boundary is in this kind of fault.
What is a strike-slip fault?
A volcano that hasn't erupted for a long time, but may erupt in the future.
What is a dormant volcano?
A hollow area in sediment in the shape of an organism that preserves fine details.
What is a mold?
The era we are currently living in is called _____ .
What is the Cenozoic Era?
The idea that Earth's plates are in slow, constant motion.
What is the theory of plate tectonics?
The point on Earth's surface directly above an earthquake's focus.
What is an epicenter?
Magma low in silica produces this kind of eruption.
What is a quiet eruption?
These fossils preserve evidence of the activities of ancient organisms.
What are trace fossils?
The sudden increase in the variety of organisms at the start of the Paleozoic Era.
What is the Cambrian Explosion?