Word Definition Translation active an active volcano is likely to erupt at any time ash the grey powder that remains after something has burned atoll an island in the form of a ring, made of coral blast a strongcurrent of air, wind, heat etc. buckle to bend or to make something bend under pressure caldera a large whole in the volcano, sometimes containing a lake, caused by the walls that form the top of the volcano falling in after an eruption happens collide if people or things collide, they crash into each other(noun collision) cone an objevt with circular base that rises to a point (adj. Conical) continental drift the very gradual movement of continents across the Earth's surface as a result of the movement of the plates that they lie on core the central part of the planet crack if something cracks, a line or long narrow hole appears on its surface, but it does not break into peaces crater the round hole at the top of volcano crust the outet layer of rock on the Earth or on another planet damage physical harm caused to something so that it is broken, spoiled, or injured delta an area where a river devides into several smaller rivers that flow into the sea devastate to seriously damage or completely destroy something dormant something that is dormant is not active or developing now, but it may become active or develop in the future earthquake a sudden movement of the ground, often causing a lot of damage to building earthquake-proof not affected by earthquakes epicentre the area of land directly over the centre of earthquake eruption the explosion of volcano (verb erupt) extinct an extinct volcano is no longer active and no longer erupts faultline a feature on the Earth's surface in which layer of rocks that have become separated from the main layer of rocks appear through the surface of the Earth flow the continuous movement of a liquid in one direction fluid liquid or gas focus the place bellow the Earth's surface where an earthquake begins (pl. Foci) fold mountain a mountain formed from the folding of the Earth's crust when two plates move together The Earth folding when plate boundaries collide and compression causes parts of the Earth's crust to become raised and buckled into mountains force physical strength, or violence formation the process during which something develops or is created heat hurl (into the air) to throw something using a lot of force hydrosphere the part of the Earth's surface that is water, including the seas and water in the atmosphere chain a series of things of the same type that form a connected jelly- like a jelly-like substance is between a liquid and a solid lava rock in the form of extremely hot liquid that flows from a volcano magma hot liquid rock inside the Earth. When magma becomes coll it forms igneous rock make up mantle the part of the Earth that is deep bellow the surface and surrounds the core melt mud-flow a large amount of wet earth that falls down a hill occur to exist or be found somewhere physical geography the type of geography that deals with the physical features of the world such as mountain and rivers plate pressure a force pressing on something protrude to be futher forward than the rest of something ridge the long narrow top of a mountain or group of mountains rift a crack or long narrow space that forms in a large mass of something such as rock ring of fire an area of frequent earthquakes and volcanic eruptions aroudn the Pacific Ocean (Pacific Ring of Fire) rotation a movement in a circle around an axis, especially the movement of the Earth aound its axis once every 24 hours seismology the scientific study of earthquakes semi-molten semi-molten rock has almost become liquid because it is so hot sink to disappear below the surface of teh water slide to move smoothly and quickly across the surface surface the top layer of water or land sway to move or swing gently from side to side terrain an area of land, usually one that has a praticular physical feature tidal wave a large wave or mass of water in the sea that is sometimes produced at high tide; a tsunami tremble to shake slightly upwards towards a higher position vent a hole in the Earth's surface through which lava or gas comes out volcano a mountain that forces gas, rocks, ash and lava into the air through a hole at the top well up if a liquid wells up, it comes to the surface and is about to flow