| A | B |
|---|
| mold | empty space in rock where remains of living thing used to be |
| reservoir | storage area for holding fresh water |
| metamorphic rock | rock formed from another rock with heat and pressure |
| watershed | land where water flows downhill to same stream lake or river |
| relative age | age of one rock or fossile compared to another |
| renewable resource | useful material replaced quickly in nature |
| compost | mixture of decaying matter that helps plants grow in soil |
| cast | fossil formed or shaped within a mold |
| reuse | to use something again |
| runoff | water that flows over land but doesn't evaporate or soak in |
| horizon | layer of soil different from soil above and below |
| rock cycle | process in which rocks continuously change from one type to another |
| soil water | water that soaks into and collects in soil |
| acid rain | harmful rain caused by burning of fossil fuels |
| imprint | fossil made by a print or impression |
| subsoil | hard layer of clay and minerals beneath topsoil |
| amber | hardened tree sap (yellow/brown) source of insect fossils |
| irrigation | bringing water to soil through pipes or ditches |
| porous | has pore spaces that water and air can pass through |
| topsoil | dark top layer of soil with lots of humus and minerals where things grow |
| fossil | evidence of organism that lived in the past |
| pollution | harmful materials that contaminate environment |
| nonrenewable resource | natural material or energy source useful to people and not easily replaced |
| fossil fuel | source of energy made from remains of ancient living things |
| sedimentary rock | rock formed when small bits of matter are pressed together in layers |
| pore space | space between particles of soil |
| conservation | saving protecting or using resources wisely |
| permeability | measure of how fast water passes through |
| resource | material or object with useful properties |
| humus | decayed plant/animal matter in soil |
| soil profile | view of different horizons in soil from surface to bedrock |
| mineral | solid nonliving substance found in nature |
| igneous rock | fire-made rock formed when melted rock cools |
| ground water | water stored in cracks and spaces of underground rock |
| reduce | to use less of something |
| recycle | to make new objects or materials from old ones |
| well | hole dug below ground to reach groundwater |
