4 th Grade Earth Science Chapter 9 Changing of Earth’s Surface

What is the Earth made of? Landforms on Earth include: – __________ – __________ - flat land – ________ - a deep crack – ______ - flatlands with few trees – _______ - on land where mountains are close together – ______ - beneath the ocean, long row of towering mountains – ________ - long narrow canyons in the ocean floor Mountains Plateaus Gorges Plains valleys Ridges Trenches

Earth’s Features Earth’s surface is made up of many different __________. Earth’s surface is constantly ________ and so are the landforms ___________ - the process of breaking down rock into smaller pieces Forces of __________ include ________ and _____ Landforms changing weathering water ice

Mechanical / Chemical Weathering _________________ - process of breaking down rock into smaller pieces as a result of ice or water – MINERALS THAT MAKE UP THE ROCK DO NOT CHANGE! ________________ - minerals that make up the rock change. The cause of chemical weathering is a _________ with something in the environment such as ____ or ________ Mechanical Weathering Chemical Weathering reaction wateroxygen

Erosion ________ - the process by which soil and sediments are transferred from one location to another The movement of soil and sediments can be caused by: – _________ – ________ – ______ – ________ erosion wind water ice gravity

Water _________ - solid particles that are moved from one place to another __________ - sediments that form during weathering and erosion are deposited in another location During the process of deposition, the _______ and ________ of a river’s flow changes As rivers flow to the oceans they carry ________ and ______________ which are useful to plants and animals to carry out their __________ deposition sediments shape direction sediments Dissolved minerals Life processes

Soil Erosion Areas of land with no plant covering are susceptible to __________ __________ - help prevent soil erosion by holding the soil in place ___________ - planted by farmers in between harvests to prevent soil erosion and add nutrients to the soil ______________ - years of drought and poor farming practices left bare areas of soil Soil erosion Plant roots Cover crops Dust Bowl of 1930’s

Soil ____ - made of weathered rock, air, water, and the remains of living things. __________ - process of breaking down rocks through physical factors such as _____, _________, _______ or__________________. ________ = non-living parts of the soil As rock breaks down small pieces collect on the surface soil weathering frost droughtChanges in temperaturerainwater inorganic

Volcanoes __________ occur when magma from the mantle either flows or explodes through the crust. – Opening in the surface of the Earth through which magma rises – Occur near ______________ – Theory of plate tectonics – one plate sinks beneath another at a plate boundary – sinking crust melts into _______. – _____ - Magma that reaches the surface Volcanoes Plate boundaries magma lava

Draw and Label Volcanoe page

Earthquakes _________ are caused by the sudden shifting of rock as tectonic plates shift positions – Pressure builds up, rocks lurch forward, and the Earth’s crust shakes. – ______ - the underground point where the earthquake occurs – ________ - point on the Earth’s surface directly above the focus. Earthquakes focus epicenter

Waves Energy from the earthquake is carried by _______. Waves spread out from the _____ and ________. Waves can cause the Earth to move ________, ___________, or in a ___________ As the waves spread out from the epicenter, they __________. waves focus Lose energy Up and down Back and forthCircular motion Volcanoes

Earthquakes and Plate boundaries ____________ and _________ have had the most earthquakes because they are located on a ____________ between the Pacific plate and the North American Plate. The strength of an earthquake can be measured on a ____________ - a series of numbers that is based on the amount of energy that is released. CaliforniaAlaska Plate Boundary Magnitude scale