Earthquake vibrations are detected, measured, and recorded by instruments called

• magnetometers
• seismographs
• Richter scales
• sonargraphs

the middle of the mantle below the lithosphere

• Athens Greece
• core
• mantle
• asthenosphere

molten, softer, liquid like layer of iron and nickel

• outer core
• inner core
• lithosphere
• asthenosphere

Earthquake activity in California is primarily caused by 

• the lowering of aquifer levels
• the interaction of tides with the coast
• plates grinding past each other along active faults
• mining activity during the 19th century

dense, solid; made of iron and nickel

• crust
• mantle
• outer core
• inner core

Which of the following best describes Earth's tectonic plates

• they move away from each other at the equator
• they move because of convection currents in the mantle
• they form at subduction zones
• they collide at midocean ridges

the crust and upper mantle

• asthenosphere
• core
• inner core
• lithosphere

the top layer of the earth; thinnest layer

• inner core
• outer core
• crust
• lithosphere

Earthquakes and volcanic eruptions most often occur

• in regions near the equator
• in large bodies of water
• on large pieces of land
• near plate boundaries

The best evidence that the continents were once connected is that they have matching

• weather, fossils, and rock types
• rock types, fossils, and coastlines
• coastlines, weather, and rock types
• coastlines, weather, and fossils