Vocabulary
erosion, chemical weathering, mechanical weathering, marine erosion, desertification, biological weathering, sand, silt, gravel, geodes, sea arches, sea glass, stalactites, stalagmites, cavern, crystallization, quartz, amethyst, resource, natural resource, renewable resource, non-renewable resource, coal, oil, solar, iron, energy, fossil fuel, fissile materials, pollution, natural resources, nonrenewable resources, renewable resources, fossil fuels, natural resources, nonrenewable resources, renewable resources, fossil fuels