This book goes on a journey underground to examine the many kinds of soil, microorganisms and inorganic matter that make it, and the critical role it plays in ecosystems around the world. Most people don't think about the soil under their feet, but basic dirt can reveal a lot about Earth's past. Soil is formed from tiny grains of rock that existed many years ago. It can also form in the wake of landslides, volcanoes, and everyday weathering. Helpful diagrams, fact boxes, and sidebars support the information-rich text, and colourful images will keep readers engaged from start to finish.