Introduction: Weathering The Breakdown of Rock At the Earth's surface, rocks are exposed to the effects of weathering: the chemical alteration and mechanical breakdown of rock, when exposed to air, moisture, and organic matter. Weathering is an integral part of the rock cycle. Weathering converts rock to regolith
Introduction: What Is an Igneous rock? Igneous rocks vary greatly. Some contain large mineral grains. Others contain grains so small they can barely be seen under a high power microscope. Igneous rocks also vary greatly in color. All igneous rocks are formed through the cooling and solidification of magma
Plate Tectonics From Hypothesis to Theory Plate tectonics is a scientific theory that explains two centuries of often puzzling observations and hypotheses a bout our planet Earth. a The continents are drifting very slowl across the face of our planet Continental drift is a concept with a long history