DESCRIBE-HOW-LAYERS-OF-ROCKS-STRATISFIED-ROCKS-ARE-FORMED.pdf

DESCRIBE HOW LAYERS OF ROCKS (STRATISFIED ROCKS) ARE FORMED WHAT IS STRATIFIED ROCKS? These rocks possess planes of stratification or cleavage and such rocks can easily be split up along these planes. Sedimentary rocks, Sandstone, limestone, slat...

DESCRIBE HOW LAYERS OF ROCKS (STRATISFIED ROCKS) ARE FORMED WHAT IS STRATIFIED ROCKS? These rocks possess planes of stratification or cleavage and such rocks can easily be split up along these planes. Sedimentary rocks, Sandstone, limestone, slates and marbles, and also stratified rocks are mostly sedimentary rocks in origin, wherein there is visible layering. Formation of these stratified rocks includes weathering, sedimentation, compaction and cementation. Layers in this rock formations are then used to determine Earth's history. Sediment Formation and Transportation 1. WEATHERING A. Physical Weathering Types (e.g., freeze-thaw, thermal expansion, abrasion) Impact on rock fragmentation B. Chemical Weathering Types - Oxidation - Hydrolysis - Dissolution - Effects on mineral composition C. Biological Weathering Impact on rock and soil formation Role of organisms - plant roots - Lichen 2. EROSION A. Agents of Erosion - Water (rivers, streams, ocean currents) - Wind (deflation, abrasion) - Ice (glaciers, ice sheets) - Erosion Processes - Soil erosion - Sediment transport mechanisms B. Landforms Created by Erosion - Valleys - Canyons - deltas 3. SEDIMENT TRANSPORTATION A. Sediment Types - Gravel - sand - silt - Clay B. Transport Mechanisms - Bed load (rolling, sliding) - Suspended load (particles carried in the water) - Dissolved load (minerals in solution) 4. SEDIMENT DEPOSITION A. Deposition Environments  - Terrestrial Environments - Riverbeds, lakes, deserts - Landforms: alluvial fans, deltas - Marine Environments - Coastal areas, deep sea - Landforms: - beaches, submarine canyons - Transitional Environments - Estuaries, tidal flats - Mixed characteristics of terrestrial and marine environments B. Sorting and Layering Sorting By particle size (e.g., well-sorted vs. poorly sorted) By particle density Layering (Stratification) Formation of distinct layers Factors influencing layer thickness and composition Formation of Stratified Rocks A. Compaction Process - Reduction of pore space - Increase in sediment density Effects - Impact on sediment texture - Changes in porosity and permeability B. Cementation Process - Precipitation of minerals - Binding of sediment particles - Common Cementing Agents - Quartz, calcite, iron oxides Types of Cementation - Authigenic (formed in place)  - Diagenetic (formed during later stages) TYPES OF SEDIMENTARY ROCKS A. Clastic Sedimentary Rocks Characteristics Formation from fragments of other rocks Types: sandstone, shale, conglomerate Grain Size and Sorting Implications for rock classification B. Chemical Sedimentary Rocks Characteristics Formation from mineral precipitation Types: limestone, halite, gypsum Formation Environments Evaporative settings, hot springs C. Organic Sedimentary Rocks Characteristics Formation from organic material Types: coal, oil shale Formation Conditions Peat bogs, marine settings with high organic productivity 5. STRATIGRAPHY AND GEOLOGICAL HISTORY A. Principles of Stratigraphy  - Principle of Superposition - Understanding layer order - Principle of Original Horizontality - Application to sedimentary layers - Principle of Lateral Continuity - Extent of strata and their continuity - Principle of Cross-Cutting Relationships - Interpreting geological structures B. Fossilization Process Conditions for fossil preservation Types of fossils - body fossil - trace fossils Applications - Biostratigraphy (using fossils to date rocks) C. Uplift and Erosion Tectonic Uplift Formation of mountain ranges Impact on sedimentary layers Erosion and Exposure Processes that expose sedimentary rock layers Impact on geological mapping and study D. Geologic Mapping Creation of Geologic Maps Techniques for mapping sedimentary layers Interpretation of map data 6. APPLICATION ON CASE STUDY A. Environmental and Economic Significance Natural Resources - Coal - Oil - natural gas - Groundwater Environmental Indicators Interpreting past climates and environments B. Real-World Examples Case Studies Famous sedimentary rock formations (e.g., Grand Canyon, Niagara Falls) Historical and contemporary examples of sedimentary rock studies