Aim: How can we explain the factors affecting weathering and erosion?

Factors Exposure Particle size Mineral Composition Climate

Exposure The closer a rock is to the Earth’s surface, the faster it will weather

Particle Size The greater the surface area a particle has, the more area that is exposed to the elements, and the faster it will weather.

Mineral Composition Different minerals have different physical and chemical properties Ex. Calcite in limestone and marble is reactive with acid, and weathers more rapidly than rocks containing quartz (which is non-reactive)

Climate Chemical weathering fastest in warm, moist climates. In cold climates, frost action most common form of weathering. Weathering is the greatest in tropical regions with high rainfall and warm temperatures.

What kind of weathering do we experience on staten island? THINK PAIR SHARE What kind of weathering do we experience on staten island?

Soils What is soil? Soil is a mixture of: air water and its solutes mineral particles from parent bedrock decaying organic matter and organisms responsible for its decay

Soil Horizons

O composed mainly of organic material a few centimeters thick not fully decomposed A Top soil. Has organic matter, bacteria, plant roots, fungi, worms etc.

B Sub-soil. Fewer organisms C Partially altered bedrock with little organic matter What starts as unweathered bedrock will, through weathering, develop into soil.

The most important factor effecting soil formation is Climate Different climates produce different soils

Soil Degradation: Soil is one of the most important factors in human civilization. Its mismanagement and destruction has been the collapse of many civilizations in the past. E.g. Sumeria in Iran/Iraq Easter Island Teotihuacan Maya