| A | B |
|---|
| anticline | a bowl-shaped fold in sedimentary rock layers |
| asthenosphere | the soft layer of the mantle on which pieces of the lithosphere move |
| compression | the type of stress that occurs when an object is squeezed |
| continental drift | the theory that continents can drift apart from one another and have done so in the past |
| convergent boundary | the boundary between two colliding tectonic plates |
| divergent boundary | the boundary between two tectonic plates taht are moving away from each other |
| fault | a break in the Earth's crust which blocks of the crust slide releative to one another due to tectonic forces |
| fault-block mountain | a mountain that forms when faulting causes large blocks of the Earth's crust to drop down relative to other blocks |
| folded mountain | a mountain that forms when rock layers are squeezed together and pushed updward |
| folding | the bending of rock layers due to stress in the Earth's crust |
| footwall | the fault block that is below a fault |
| hanging wall | the fault block that is above a fault |
| inner core | the solid, dense center of the Earth |
| lithosphere | the outermost, rigid layer of the Earth that consists of the crust and the rigid upper part of the mantle |
| magnetic reversal | the process by which the Earth's north and south magnetic poles periodically change places |
| mantle | the layer of the Earth between the crust and the core |
| mesophere | the middle shpere, the strong lower part of the mantle between the asthenosphere and the outer core |
| mid-ocean ridge | a long mountain chain that forms on the ocean floor where tectonic plates pull aprt, usually extends along the center of the ocean basins |
| monocline | a fold in sedimentary rock layers in which the layers are horizontal |
| normal fault | a fault in which the hanging wall moves down relative to the footwall |
| outer core | the liquid layer of the Earth's core that lies beneath the mantle and surrounds the inner core |
| plate tectonics | the theory that the Earth's lithosphere is divided into tectonic plates that move around on top of the asthenosphere |
