ESCI 1001 Lecture 4: Earth and its Environments Lecture Notes Week 4
Document Summary
Process of converting rock into sediment and forming soils, a main process in the rock cycle. Produces all soils, clays, sediments and dissolved substances. Soil: breaks down rocks/minerals to form soil. Life: releases elements from minerals, providing nutrients for biological processes. Climate: co2 can be released or absorbed during weathering, affecting climate. Interaction and feedback among lithosphere, atmosphere and hydrosphere (ex. Physical: rocks break down mechanically into smaller pieces- creates more surface area for chemical attack. Chemical: rocks break down chemically and change composition- creates areas of weakness that may help physical weathering processes. Main agent: water solutions behave as weak acids (even rain) Silicate minerals clay (hydrolysis) (feldspar + h2o = clay minerals b/c feldspar attacked) Iron interacts with the water and oxygen in the water (rust) Fe in silicate fe + oxygen (oxidation of iron-rich minerals in sedimentary rocks) Chemical weathering of iron-rich minerals in rocks such as basalt: dissolution. Main products: new minerals, ions in solution.