elements

• continental plates are less dense than oceanic plates as they contain more silicon and aluminum which make them lighter.
• continental plates are less dense than oceanic plates as they contain more silicon and aluminum which make them lighter.
• oceanic plates are denser than continental plates because they have more iron and magnesium which makes them heavier.
• the earth's crust is made up of two types of plates, oceanic and continental
• the lithosphere is the rigid outer layer of earth that consists of the crust and upper mantle
• the lithosphere is the rigid outer layer of earth that floats on top of the asthenosphere
• convection currents occur when hotter material rises up through cooler material due to differences in density
• convection currents occur when hotter material rises to replace cooler material
• the asthenosphere is the lower part of the mantle where rocks can flow slowly over time, allowing continents to move on top of it
• the asthenosphere is the semi-molten rock below the lithosphere, it can flow slowly over time
• plates move due to convection currents within the mantle
• hot spots are areas where molten rock from the mantle reaches the surface
• convection currents occur when hotter material rises and cooler material sinks
• the asthenosphere is the lower part of the mantle where rocks can flow slowly over time
• convection currents occur when hotter material rises to replace cooler material below it
• plate boundaries form where two or more plates meet
• divergent plate boundaries occur at mid-ocean ridges where new crust forms by volcanism
• continent drift refers to the movement of land masses across the surface of the Earth
• divergent plate boundaries form mid-ocean ridges
• constructive margins occur at divergent plate boundaries where new crust forms by volcanism
• plate movement occurs at divergent boundaries where new crust forms as molten rock from the mantle fills gaps between separating plates
• plate movement occurs at divergent boundaries where new crust forms as molten rock from the mantle fills gaps between separating plates
• at convergent plate boundaries one plate moves under another (subduction)
• at convergent plate boundaries one plate moves under another (subduction)
• plate boundaries are areas where two or more plates meet
• plate boundaries are areas where two or more plates meet
• continental drift refers to the movement of land masses across the surface of the Earth
• hotspots are caused by magma rising from deep inside the earth
• a divergent boundary occurs at mid ocean ridges where magma fills gaps between plates as they pull apart
• continental drift was proposed by Alfred Wegener who suggested that all land masses were once joined together as one super continent called Pangaea
• divergent plate boundary occurs when two plates move away from one another
• continental drift was proposed by Alfred Wegener who suggested that continents were once joined together as one super continent called Pangaea
• Wegner's evidence for continental drift included fossil records showing similar species across different continents, matching coastlines and mountain ranges, and the fit between South America and Africa
• magma is molten rock that has not yet reached the surface
• a mid oceanic ridge is an underwater mountain range that runs through the Atlantic Ocean
• Wegener's evidence for continental drift included fossil records showing similar species across different continents, matching coastlines and mountain ranges, and the fit between South America and Africa
• Alfred Wegener's theory of continental drift was rejected because there was no explanation for how continents could have moved apart from being pushed by an invisible force or floating on water
• volcanoes form at plate boundaries or above hotspots
• divergent plate boundary occurs when two plates move away from one another, creating new crust at mid-ocean ridges
• constructive margins occur at divergent plate boundaries on land, such as the East African Rift Valley