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GEOL 446 Environmental Geology. PART I FOUNDATIONS OF ENVIRONMENTAL GROLOGY. 1. Philosophy and Fundamental Concepts. 2. Earth Material and Processes. 3. Soils and Environment. Earth Materials and Processes. Learning Objectives:
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GEOL 446Environmental Geology PART I FOUNDATIONS OF ENVIRONMENTAL GROLOGY 1. Philosophy and Fundamental Concepts 2. Earth Material and Processes 3. Soils and Environment
Earth Materials and Processes • Learning Objectives: • Acquire basic understanding of the geologic cycle and its sub-cycles (tectonic, rock, hydrologic, and biogeochemical). • Make a modest acquaintance with some of the important mineral and rock types and their environmental significance. • Gain an appreciation of the landforms, deposits, and environmental problems resulting from wind and glacial processes.
Earth Materials and Processes The Rock Cycle Tectonism controls the rock cycle and is important to many surficial processes and other Earth Cycles.
Units are relative to annual P on land surface 100 = 119,000 km3/yr)
The Biogeochemical Cycle • The Biogeochemical Cycle traces the movement of an element, like carbon, in the air, water, on and in the land, and as used by living organisms. This issue is of particular importance today because large amounts of carbon dioxide are produced by burning fossil fuels. Many scientists are concerned that this trapped carbon dioxide may heat the earth in a process known as the "greenhouse effect." Carbon Cycle
Strength of Rocks • Rock strength is highly variable. • Many Factors: • rock type • texture • chemical composition • internal structures • presence or absence of fluids • Most rocks already fractured by joints and faults. • Fractured rocks are only as strong as whatever is holding the rock together (gravity or friction). • fracture along planes of weakness • fracture along bedding planes or along foliation planes • orientation of planes of weakness is important, Why? Table 2.1
Terms to Understand • hydrocompaction • geologic cycle • tectonic cycle • rock cycle • hydrologic cycle • biogeochemical cycle • greenhouse effect • rock strength • reliable strength • safety factor • stress and strain • ductile and brittle substances • elastic and plastic deformation • proportional elastic limit • ultimate strength • rupture strength
Read Case Histories in the textbook: Baldwin Hills Dam and St. Francis Dam