PPT-Sedimentary structures

Geology 103 Depositional environment Is the term given to the area where the sediment was originally deposited Must be inferred from the rock identity Clastic depositional environments Dominated by actions of waves tides and currents. Colby Geology. Igneous Rocks. Classification based on . composition. and . texture. .. COMPOSITION. Principally the rock-forming minerals. Olivine. Pyroxenes. Amphiboles. Micas. Feldspars. Quartz. Constitute 95% of minerals in . Sedimentary rocks cover ~ 75% of Earth’s surface. ~ 5 % (by volume) of Earth’s outer 10 miles. Contain evidence of past environments:. Important resource. Coal, oil, and other fossil fuels. Groundwater resources. Chemical Sedimentary Rocks. . Limestone. Chert – Silica. Evaporites. Organic Rocks. Coal. Oil and natural gas. Clastic Sedimentary Rocks. Formed from clasts (bits and pieces of pre-existing rocks) transported, deposited,and lithified. OR. Strategy:. Relate sedimentary characteristics of ancient deposits (grain size, . sedimentary . structures, geometry) to features observed in modern rivers. Bedforms. during traction deposition from unidirectional flow. Kinematic analysis of deformation. B. Natalin. Structural geology and tectonics. Structural geology is the study of deformation of rocks. - we study such features as folds, faults, their geometry, movements, origins;. Types of Rocks. Sedimentary Rocks. Metamorphic Rocks. Igneous Rocks. Sedimentary Rocks. How They are Made. Wind and water break down the earth. Bits of earth settle in lakes and rivers. Layers are formed and build up. What You Will Learn. Describe the origin of sedimentary rock. . Describe the three main categories of sedimentary rock. . Describe three types of sedimentary structures. . Where does Sand come from?. Favs. .. . Where do sediments come from?. - Weathering. – breaking down rock into smaller pieces chemically and physically.. - Erosion. - carrying away the particles and depositing them. . Glaciers. Microbial assemblages (in biofilms) form sticky films that influence sediment deposition. Microbially. -bound sediments are stabilized and more cohesive. Microbialite. : a rock formed via the influence of microbial trapping, binding, and precipitation. TRANSPORT MEDIA. Gravity. . is the . simplest mechanism of sediment . transport.. It includes the . movement of particles under gravity . down a . slope. .. Rock falls generate piles of sediment at . Sedimentary structures. Sedimentary structures.  are those structures formed during sediment deposition. .. Sedimentary structures such as . cross bedding, graded bedding, mud . cracks, . Strata. Kinematic analysis of deformation. B. Natalin. Structural geology and tectonics. Structural geology is the study of deformation of rocks. - we study such features as folds, faults, their geometry, movements, origins;. Sediment . Texture. Sediment texture refers to the shape, size and three-dimensional arrangement of the particles . that make . up sediment or a sedimentary rock.. Textures can be . clastic or . crystalline. Do Now. 1.  What is an igneous rock?. 2. How do sedimentary rocks form?. Sedimentary Rocks -. are one of the three main rock types . A sedimentary rock can form one of three ways: . by the . deposition.