Grade 4 - NGSS - CA
Earthquake
A sudden shaking of rock in the Earth's crust. Earthquake. An earthquake is the shaking of the ground caused by movements of rocks below the Earth's surface.
Flood plain
A wide valley through which a river flows and can overflow. Flood plain. A flood plain is a flat area next to a river that can get covered with water when the river overflows.
Hurricane
A large tropical storm with winds of more than 74 mph. Hurricane. A hurricane is a big spinning storm that forms over warm ocean water and can cause strong winds and heavy rain.
Landslide
The sudden movement of loose rock and soil down a slope. Landslide. A landslide happens when dirt and rocks quickly slide down a hill or mountain.
Tornado
A spinning funnel-shaped column of wind. Tornado. A tornado is a strong windstorm that forms a spinning cloud shaped like a funnel and can cause lots of damage.
Tsunami
A huge wave caused by an underwater earthquake. Tsunami. A tsunami is a big ocean wave caused by the movement of the earth under the sea.
Volcano
A mountain through which lava flows to Earths surface. Volcano. A volcano is an opening in the Earth's surface that lets hot, melted rock and gases escape.
