Geology PDF

Geologists engineering to develop a specific mineral who study the origin, occurrence, resource. Mining Geology distribution and utilities of all materials 11. Spectral Geology. Spectral geology is the (metallic, non-metallic, i...

Geologists engineering to develop a specific mineral who study the origin, occurrence, resource. Mining Geology distribution and utilities of all materials 11. Spectral Geology. Spectral geology is the (metallic, non-metallic, inorganic, etc.), measurement and analysis of portions of the minerals, rocks, sediments, soils, water, oil and electromagnetic spectrum to identify all other inorganic natural resources. spectrally distinct and physically significant Branches of Geology features of different rock types and surface 1. Structural Geology - It deals with the materials, their mineralogy and their configuration of the rocks in the Earth's crust alteration signatures. produced due to a number of forces 12. Marine Surveying. The survey generated. environment varies from oceanographic 2.Geomorphology - it is how topographic and studies in the water column to investigating bathymetric features are formed and evolve sediment and geochemical processes on the through physical, chemical, or biological seafloor and imaging the sub-seafloor rocks. processes that occur at or near the Earth's Branches of Geology surface. 1. Mineralogy: The study of the characteristics 3. Crystallography - The study of the external of minerals forms and internal atomic structure of 2. Geophysics: This section focuses on the crystalline materials. structure, physical conditions, and 4. Petrology - The scientific study of rocks evolutionary history of the earth as a whole. involves examining their composition, texture, 3. Physical Geology: This covers the and structure. It also explores their geological processes that cause changes in occurrence, distribution, and origin in relation the Earth's crust and surface. It also covers the to physico-chemical conditions and geologic surface features of the Earth, such as processes. landforms and topography. 5. The science of describing and classifying 4. Mining Geology deals with the method of layers in sedimentary rocks, along with mining of rocks and mineral deposits on the interpreting the environments in which they earth’s surface and subsurface. were formed. Stratigraphy 5. This involves the application of geological 6. The science that studies the fossils of knowledge in the field of civil engineering to animals and plants that lived billions of years ensure the safe, stable, and cost-effective ago. Paleontology construction of structures such as dams, 7. It focuses on the distribution and bridges, and tunnels. Engineering Geology movement of groundwater within the soil and 6. Geodesy: Study of Topographic Maps and rocks found in the Earth's crust, typically in Contour Maps, e.g. Remote Sensing aquifers. Hydrogeology 7. The discipline of geology utilizes principles 8. Seismology – study of the structure and and techniques to reconstruct and composition of the Earth through seismic comprehend Earth's past geological history.: waves, and of surface deformations during Historical Geology earthquakes and seismic hazards. 8. Oceanography: The study focuses on the 9. The scientific discipline employs the tools composition and motion of the water column, and principles of chemistry to elucidate the as well as the processes responsible for this underlying mechanisms governing crucial motion. geological systems, including the Earth's 9. Sedimentology : The study focuses on crust and oceans. Geochemistry analyzing sediment grains found in marine 10. It is an applied science that combines the and other deposits. It aims to understand principles of economic geology and mining their physical properties and the processes Compositional Layers of the Earth involved in deposit formation. Crust 10. Geochronology: A branch of geoscience The outermost solid layer of a rocky planet or that focuses on determining the age of Earth natural satellite. Chemically distinct from the materials. It serves as a vital tool for underlying mantle. interpreting other geoscience data within the Chemically distinct from the underlying context of Earth's history. mantle. 11. Biostratigraphy. Biostratigraphy is the Depth: 0 - 100km silicates branch of stratigraphy that uses fossils to Mantle establish relative ages of rock and correlate Layer between the crust & outer core successions of sedimentary rocks within and chemically distinct from the crust and the between depositional basins. outer core 12. Geochronology is a discipline of not liquid, however, ductile, or plastic, which geoscience which measures the age of earth means that on very long time scales and materials and provides the temporal under pressure it can flow mainly composed framework in which other geoscience data of aluminum and silicates can be interpreted in the context of Earth Depth: 100 – 2,900 km iron and magnesium history. silicates 13. Topography is the study and description of Core the physical features of an area, for example, innermost layers its hills, valleys, or rivers, or the representation chemically distinct from the mantle of these features on maps. mainly composed of nickel and iron. Scope of Geology to Civil Engineering Depth: 2,900-6,370 km metals 1. Site Investigation Mechanical Layers of the Earth a) Soil and Rock Analysis LITHOSPHERE b) Geotechnical Surveys The outermost, rigid layer of the Earth. 2. Foundation Design Made of two parts: the crust and the Moho a) Foundation Types (upper solid part of the mantle). b) Stability Assessments Divided into pieces called tectonic plates. 3. Earthworks and Excavation ASTHENOSPHERE a) Material Selection The soft layer of the mantle on which the b) Excavation Techniques lithospheric plates move. 4. Water Management It is made of solid rock like putty that flows a) Hydrology and Hydrogeology very slowly – about the same rate your b) Dewatering Techniques fingernail grows. 5. Environmental Considerations MESOSPHERE a) Contamination Assessment The strong, lower part of the mantle. b) Sustainability Practices Extends to the Earth’s core 6. Seismic Risk Assessment OUTER CORE a) Earthquake Engineering extends from the bottom of the mantle and 7. Geological Hazards surrounds the inner core. a) Risk Mitigation Liquid and hot 8. Infrastructure Development composed of liquid iron and nickel a) Transportation Projects INNER CORE b) Urban Planning Solid (Due to pressure from upper layers.) Composed of iron. Plate Tectonics -​ the massive, irregularly shaped slabs of -​ occurs where one plate with oceanic crust rock that make up the Earth’s lithosphere sinks, or subducts, under another plate -​ One plate cannot shift without affecting with oceanic crust the others nearby -​ Most are found in the Pacific Ocean -​ Plates can move apart, push together or Oceanic – Oceanic Convergence scrape each other ISLAND ARCS Plate Tectonics Theory -​ chains of volcanic islands that form on the -​ states that Earth’s plates are in slow, top plate, parallel to a deep-ocean trench constant motion, driven by convection Oceanic – Continental Subduction currents in the mantle -​ occurs when ocean crust sinks under -​ Satellites are used to measure plate continental crust precisely Oceanic – Continental Subduction -​ 1 – 12 cm per year DEEP – OCEAN TRENCHES **Convection currents describe the rising, -​ As the ocean crust moves, it often causes spread, and sinking of gas, liquid, or molten underwater earthquakes material caused by the application of heat. COASTAL MOUNTAINS Plate Motion over Time -​ As oceanic crust sinks under a continent, Geologists have evidence that before Pangea the continental crust buckles to form a existed, other supercontinents formed and range of mountains parallel to the split apart over the last billion years deep-ocean trench Plate Boundaries -​ Cascade Mountains in Oregon and -​ occurs where plates move apart Washington (Mount St. Helen’s) -​ Mid-Ocean Ridges -​ Rift Valleys -​ Magnetic Stripes Plate Tectonics Boundaries -​ Divergent Boundaries ​ Mid-Atlantic Ridge -​ World’s longest ridge ​ Iceland Plate Boundaries -​ On top of Mid-Atlantic Ridge -​ occurs where plates scrape past each ​ Great Rift Valley other -​ Ethopia, Kenya, Tanzania & -​ crust is neither created nor destroyed Mozambique -​ occur mostly on the sea floor near the -​ Above sea level mid- ocean ridges, but they can occur on - occurs where plates push together land where some are clearly visible as - crust either folded or destroyed long cracks in Earth’s surface - Inner-Continent Mountains How Plate Tectonics Helps Geologists - Coastal Mountains -​ explain Earth’s past and to predict what - Deep-Ocean Trenches (Subduction) might happen along plate boundaries in - Island Arcs the future Continental – Continental Collision -​ can uncover the history of any region on -​ occurs when two plates carrying Earth continental crust push together -​ The folded crust can be pushed up high enough to form mountains Oceanic – Oceanic Subduction Continental Drift Theory ALFRED WEGENER -​ German meteorologist who proposed the Continental Drift Theory -​ Continents were once a one large landmass (PANGAEA / PANGEA) 200 MYA WEATHERING IN GEOLOGY Weathering - is the breakdown of rocks into sediments, providing raw material for other rocks and for the formation of soils. Erosion - is the transport of the resulting sediments by natural forces like wind, running water, ice, and gravity. Why Weathering is important? -​ Breaks down rocks and minerals for soil creation. Which is the primary source of inorganic material that provides food and oxygen to vegetation growth. -​ Creates landforms like mountains, valleys, canyons, and plateaus. Types of Weathering -​ Physical Weathering: Breakdown of rocks without changing their composition. -​ Chemical Weathering: Alteration of the A controversial Idea – Why? chemical structure of rocks -​ “How did the continents drift apart?” -​ Biological Weathering: Contribution of REJECTED living organisms to rock breakdown. -​ Theory: moved by the spin of the Earth Physical Weathering Processes -​ Not enough evidence -​ Frost Wedging: Water freezes and expands in rock cracks. -​ Thermal Expansion: Rocks crack due to repeated heating and cooling. -​ Abrasion: Friction from wind, water, or ice wears down rocks. -​ Exfoliation: Outer layers of rocks peel off. Chemical Weathering Process Negative Impacts: 1.​ Dissolution: Minerals dissolve in water 1.​ Structural Damage: Weakens rocks (e.g., limestone) and buildings. 2.​ Oxidation: Minerals react with oxygen, 2.​ Soil Degradation: Reduces fertility. forming oxides like rust. 3.​ Economic Costs: Damage to 3.​ Hydrolysis: Water reacts with silicates to infrastructure. form clays. Conclusion 4.​ Carbonation: Carbon dioxide reacts with 1.​ Weathering is a vital geological process water to dissolve carbonate rocks. that shapes the Earth's surface. Biological Weathering Processes 2.​ It involves physical, chemical, and 1.​ Root Action: Plant roots grow into cracks biological mechanisms influenced by and split rocks. various factors. 2.​ Lichen and Moss: Release acids that 3.​ Impacts include soil formation, landform chemically alter rocks. creation, and structural changes. 3.​ Burrowing Animals: Expose rocks to air 4.​ Allow us to mitigate these effects and and water, enhancing weathering. sustainably manage Earth’s landscape and Factors Affecting Weathering resources. 1.​ Climate: Humid climates favor chemical 5.​ Weathering plays an essential role in weathering; cold climates favor physical supporting life and regulating the weathering. environment. 2.​ Rock Type and Composition: Soluble Earthquake rocks like limestone weather faster. An earthquake is the shaking of the Earth's 3.​ Topography: Steep slopes experience surface caused by the sudden release of more physical weathering. energy in the lithosphere, creating seismic 4.​ Biological Activity: Dense vegetation waves. increases weathering. Types of Earthquakes 5.​ Time: Longer exposure leads to more 1.​ Tectonic Earthquakes: Caused by the weathering. movement of tectonic plates. Causes of Weathering 2.​ Volcanic Earthquakes: Associated with 1.​ Environmental Forces: Temperature volcanic activity. changes, water, wind, and ice. 3.​ Collapse Earthquakes: Due to cave-ins or 2.​ Chemical Reactions: Interaction of water explosions underground and gases with minerals. Causes of Earthquake 3.​ Biological Activities: Roots, -​ The Earth's crust is divided into tectonic microorganisms, and burrowing animals. plates that move constantly. 4.​ Image: Infographic illustrating these -​ Plate movements create stress in the causes crust, especially at plate boundaries. Impacts of Weathering -​ Stress builds when plates get stuck, Positive Impacts: forming faults (cracks in the crust). 1.​ Soil Formation: Essential for -​ The sudden release of built-up pressure agriculture. causes earthquakes, with energy 2.​ Nutrient Release: Supports released as seismic waves. ecosystems. -​ This process is explained by the Plate 3.​ Landform Development: Creates Tectonics Theory, which describes the unique landscapes. movement and interactions of Earth's plates. Earthquake facts By Deposition of Wind Seismic Wave: Energy waves that travel THE PROCESSES through the Earth's layers, causing ground Ecosystem shaking during an earthquake. Biotic Factors Epicenter: The point on the Earth's surface Abiotic Factors directly above the earthquake's origin, where Causes of Geological Works of the Winds seismic waves are felt most strongly. -​ Wind Generation Focus (Hypocenter): The location within the -​ Topographical Earth where the earthquake begins, releasing -​ Influence energy that generates seismic waves. -​ Climate Conditions Geological Works of the Wind Impact of Geological Works of the Winds Wind -​ Erosion Wind, along with rivers and glaciers, is a key -​ Transportation force shaping the Earth’s surface. The Suspension alterations it causes are largely a result of its Saltation movement, which can lead to either Surface Creep temporary or permanent changes. These -​ Deposition changes take the form of surface features, Geological Works of Bodies of Water influenced by factors such as wind speed, What do you mean by geological work of volume, surface characteristics, and the bodies of water? duration of the wind’s activity. For instance, Geological work of the bodies of water strong winds sweeping over loose, dry soil or means: desert regions can create temporary surface This is how the bodies of water, such as features. oceans, seas, lakes, glaciers, reservoir, puddles Methods of Erosion and rivers contributed on shaping the Earth's For wind to play a significant role in erosion, surface. solid rock must first be broken down into Types of bodies of water small, loose fragments through chemical and 1.​ Oceans mechanical weathering, allowing the wind to 2.​ Seas pick them up and carry them away 3.​ Lakes -​ Deflation 4.​ Glaciers -​ Wind Abrasion 5.​ Reservoir -​ Attrition by Wind 6.​ Puddles Factors 7.​ Rivers -​ Wind Speed and Direction Oceans -​ Surface Texture -​ An ocean is a vast body of saline water -​ Vegetation Coverage that covers approximately 71% of Earth's -​ Particle Size surface. Oceans are essential components -​ Climate Condition of Earth's hydrosphere, playing a critical Processes role in climate regulation, supporting By Wind Erosion marine ecosystems, and serving as a vital Deflation source of food, transportation, and Abrasion resources for humans. Oceans are also Attrition integral to the global water cycle, carbon By Transporting Power of Wind cycle, and Earth's overall environmental Saltation balance. Suspension  -​ are saltwater bodies with an average powerful waves that can cause significant salinity of about 35 parts per thousand. coastal erosion and damage They host numerous organisms, ranging Waves from microscopic plankton to the largest Waves are the primary force shaping animals on Earth, such as whales. coastlines. -​ Oceans vary from shallow coastal regions Hydraulic Action: The force of the wave to deep trenches, with the Mariana crashing against cliffs creates air pockets that Trench being the deepest point. These compress and explode, weakening the rock. complex current systems redistribute Current heat, nutrients, and gases across the Ocean currents are powerful forces that planet, which in turn influences weather transport vast amounts of sediment across patterns and ecosystems. great distances. FIve Major Oceans: Deep Ocean Currents: These currents, driven -​ Pacific Ocean by differences in water temperature and -​ Atlantic Ocean salinity, transport heat and nutrients around -​ Indian Ocean the globe. -​ Southern Ocean Cause of geological work of ocean -​ Arctic Ocean Earths Formation Factors that affect the geological work of The ocean originated during the Earth's ocean cooling process as the temperature dropped, Climate change with rocks forming the first expansive bodies Sea-Level Rise: As global temperatures rise, of water that would become the primordial ice caps and glaciers melt, causing sea levels ocean. This transformation laid the foundation to rise. This can lead to increased coastal for the diverse ecosystems that would later erosion, flooding, and the loss of coastal thrive in the depths of the seas. habitats. Ocean Currents Ocean Warming: Rising ocean temperatures Ocean currents are intricate movements of can lead to more frequent and intense seawater that significantly influence the storms, which can increase coastal erosion. Earth's climate and support marine Tides ecosystems. When winds blow across the The rising and falling tides constantly move ocean's surface, they impart energy to the water and sediment, contributing to the water, creating surface currents like the Gulf erosion and deposition of coastal features. Stream, which carries warm water from the Plate Tectonics Gulf of Mexico to Europe. At mid-ocean ridges, molten rock rises from Erosion the Earth's mantle, creating new oceanic As waves crash against shorelines, they exert crust and pushing existing crust away from powerful forces that gradually wear away rock the ridge. This process shapes the ocean floor and sediment. This process, known as coastal and creates underwater mountain ranges. erosion, is influenced by factors such as the When tectonic plates collide, one plate can intensity of storm waves, tidal movements, slide beneath another, creating deep ocean and the composition of the coastal materials. trenches. This process also contributes to Waves volcanic activity and the formation of island surface waves are formed through the arcs interaction between wind and the surface of Earthquakes, often associated with plate the water. As the wind blows across the water, boundaries, can trigger tsunamis, which are it generates friction that transfers energy to the water, causing it to form ripples and larger providing a significant source of protein for waves. billions of people globally, particularly in Plate Tectonics coastal communities. The cooling of the Earth's mantle significantly Process of geological work of ocean influences the dynamics of plate tectonics in 1 Erosion oceanic regions. This geological process is Erosion is the first step. responsible for the formation of mid-ocean Hydraulic Action: Waves crash against cliffs, ridges, where tectonic plates diverge and new compressing air within cracks. This pressure oceanic crust is created as magma rises to the weakens the rock. surface. Abrasion: Waves carry rocks and pebbles, Impact of geological work of ocean acting like sandpaper to grind away at the cliff Climate Regulation face. Ocean currents operate similarly to a Corrosion: Seawater dissolves certain types of conveyor belt, transferring warm water and rock. precipitation from the equator toward the Attrition: Rocks collide with each other poles, and cold water from the poles back to during wave action, breaking down into the tropics. This circulation plays a crucial role smaller pieces. in regulating climate by distributing solar 2 Transportation energy more evenly across the Earth's surface, Erosion creates the material the eroded which helps to maintain stable weather material (rock fragments, sand, etc.) is now patterns and ecosystems. available for transport. Heat Redistribution Waves approach the shore at an angle, Deep-ocean currents and surface currents in carrying sediment up the beach. The the open ocean playare important in backwash carries it back down, but at a slight distributing heat around the planet. Any angle, gradually moving sediment along the alterations in the strength or patterns of these coast. ocean currents can greatly influence the Ocean currents, driven by wind and tides, global climate, potentially leading to transport sediment over longer distances. significant environmental changes. 3 Deposition Geological Data As waves lose energy they can no longer carry Data obtained from the ocean floor and the the sediment they were transporting. underlying subseafloor can provide valuable Sediment accumulates, forming beaches. insights into historical climate change, Longshore drift creates spits when it enabling researchers to trace shifts in climate encounters a change in coastline direction. over geological time frames. This information Submerged or partially submerged ridges of is crucial for evaluating patterns of pollution sand or gravel form where currents slow in offshore environments, helping to identify down. the sources and impacts of contaminants on Wind can transport sand away from the marine ecosystems. beach, forming dunes. Marine Ecosystem Seas The ocean is a vast and intricate environment The sea is a large body of saltwater that covers teeming with biodiversity, home to millions of approximately 71% of the Earth's surface. It is a species ranging from microscopic plankton to vital component of the Earth's ecosystem, majestic whales. These marine ecosystems supporting various forms of marine life. A are not only vital for sustaining the marine life great body of salt water that covers much of within them but also play a critical role in the earth. human life. They support food security by Seas are smaller than oceans and are usually atmospheric oxygen levels, as marine located where the land and ocean meet. organisms, like algae, produce oxygen Typically, seas are partially enclosed by land. through photosynthesis. Used in a particular sense the word sea Factors that affects the geological work of denotes sections of water, such as the seas Mediterranean Sea, as well as certain large, Tides entirely landlocked, saltwater lakes, such as The rise and fall of sea levels, primarily caused the Caspian Sea. by the gravitational pull of the moon and sun, The sea moderates Earth's climate and has affect the coastal areas. important roles in the water, carbon, and Geography nitrogen cycles. The location and shape of the surrounding Process of geological work of sea land masses can significantly influence the Ocean Formation: water characteristics, such as temperature Sea floor spreading, plate tectonics, and and salinity. Enclosed seas are often more volcanic activity. affected by human activity and have limited Water Cycle: water exchange with the ocean. Evaporation, condensation, precipitation, and Temperature runoff. Ranges from -1.8°C (Antarctic) to 30°C Marine Ecosystems: (tropical). Phytoplankton, zooplankton, fish, and marine Current mammals interact. Ocean circulation driven by wind, tides, and Ocean-Atmosphere Interaction: thermohaline circulation Gas exchange, heat transfer, and weather Salinity patterns. Concentration of dissolved salts (average 3.5%) Evaporation: Impact of Geological work of seas Water from the sea's surface evaporates due Rising Sea Levels: to the heat from the sun, contributing to The melting of polar ice caps and glaciers, cloud formation and the global water cycle. combined with thermal expansion (water Upwelling: expanding as it warms), leads to higher sea The upward movement of cold, nutrient-rich levels, threatening coastal cities and water from the deep ocean to the surface, communities. often occurring along coastlines. This process Ocean Acidification: supports marine life by replenishing nutrients Increased CO2 levels in the atmosphere are for plankton and fish. absorbed by the oceans, causing a drop in pH Sedimentation: levels. This harms marine life, particularly The process in which particles, such as sand, shellfish and coral reefs, which rely on calcium mud, and organic materials, are deposited on carbonate to form shells and structures. the seabed. This occurs due to currents, river Loss of Biodiversity: runoff, and erosion of coastal landforms. The degradation of marine habitats due to Photosynthesis: pollution, overfishing, and climate change Marine plants, such as phytoplankton, absorb leads to the loss of marine species, such as sunlight and carbon dioxide, producing coral reefs, fish, and other marine organisms, oxygen and forming the base of the marine disrupting ecosystems. food chain. Erosion and Habitat Loss: Oxygen Exchange: Rising sea levels and extreme weather events The sea plays a significant role in maintaining lead to the erosion of coastlines, destroying habitats for animals such as sea turtles, birds, the depression then fills with water. This and other coastal wildlife. depression is full of precipitation or ground Cause of Geological work of sea water that acts on its own to rise. These lakes Climate Change: can include some chemicals and compounds Global warming causes sea surface belonging to outer space in the sediment of temperatures to rise, which affects marine the meteorite. species and ecosystems. Melting ice caps and Shoreline Lake glaciers contribute to rising sea levels. A shoreline lake is situated near the shore of Overfishing: an ocean or sea. This usually occurs on a Over-exploitation of fish stocks depletes situation where sand and sediment is swept marine populations, disrupts food webs, and to build a wall around an area that was affects local economies dependent on fishing. hitherto connected to the ocean or sea. This is Pollution: because when there is a sandbar close to a Waste disposal, oil spills, plastics, and shore additional sand can be accumulated by chemical runoff pollute seas, harming marine the waves. This process can build the sandbar life and ecosystems. above the water line, trap a space, and make a Coastal Development: water body such as a lake. Shoreline Lake in Construction of ports, cities, and tourism California was created mainly in this manner infrastructure can damage coastal but was completed through human ecosystems, increase pollution, and lead to intervention. habitat loss for marine life. Aeolian Lake Lakes If by wind a lake is formed, then it is known as Lake, any relatively large body of slowly aeolian lake. Visualize two giants sand hills moving or standing water that occupies an and the wind is blowing the sand to form a inland basin of appreciable size. Definitions circle around the low lying valley in between. that precisely distinguish lakes, ponds, This dammed depression can increase as a swamps, and even rivers and other bodies of lake. These are also referred to as interdunal nonoceanic water are not well established. It lakes. One of the interdunal or aeolian lakes is may be said, however, that rivers and streams the Clear Lake in Oregon. are relatively fast moving; marshes and Solution Lake swamps contain relatively large quantities of When they are formed in bedrock or the rock grasses, trees, or shrubs; and ponds are is removed by weathering it can be refilled relatively small in comparison with lakes. with water forming a solution lake. Such Geologically defined, lakes are temporary cavities are usually replenished through bodies of water. groundwater, yet sometimes they can be Types of Lake refilled by precipitation as well. Anthropogenic Lake Tectonic Lake A human made lake is the one that has been A tectonic lake is formed when tectonic created by man or at least influenced by him. activities have influenced the geographical These are often developed when individuals structure of the earth affecting the formation erect a dam or construct a reservoir. These are of faults or when land has sunk in some areas those that are filled with precipitation, because of movement of tectonic plates. aquifers or a river that has been gauged or These types of lakes are often deep and big, dammed. they are usually formed on depressions which Meteorite Lake are result of the Earth’s crust shift. This is a depression that is created after a meteor hits on the surface of the earth and Glacial Lake 2.​ It forms slowly and begins to accumulate A glacial lake is a water body created from a water from precipitation, groundwater, depression caused by glacier activity or mass- riverborne, melting of ice caps or oceans wasting that is subsequently filled with water in the areas that are near the seas or mainly from the melting process or direct lakes. precipitation. These lakes may be very deep 3.​ The water in the depression tends to pile and generally, they are situated in a U-shaped up and is stored right from the time it valley resulting from the erosive influence of gets into the lake as long as the inflow glaciers. (quantity of water that flows into the lake) Volcanic Lake equals the outflow (quantity of water that A volcanic lake is a lake that occurs in a flows out of the lake), some of the lakes volcanic crater or caldera, which may have do not have outflow and hence become been formed during an eruption period. The endorheic. resulting depression can then hold water 4.​ As the lake develops, silt brought in by whether through rain water or ground water water flow, soil erosion and decaying to form a lake. plant materials settle at the base, thus River (Fluvial) Lake altering the contours, depth and quality A river lake is formed where a river takes a of water of the lake. This process together new course or a series of curves, like an with the control and regulation of the oxbow, forming a water body isolated in a water cycle can contribute to the while. These lakes can be encountered in maturing of the lake like the process of floodplains and are usually created by eutrophication whereby the nutrients and sediments deposition or rivers erosion plant life in the lake are enhanced. Landslide (Dam) Lake Factors that affects the geological work of An individual landslide lake is formed when a lakes river or a valley is blocked by a landslide or a The creation, properties, and ecology of lakes rockfall; this acts like a natural barrier. The are determined by a variety of variables, deposition of the landslide results in the making them exceptional natural features. To formation of a lake in the depression since the appreciate the variety of lakes and their water cannot escape. importance to our ecosystem, it is essential to Coastal Lake (Lagoonal Lake) comprehend these elements. A coastal lake is a lacustrine environment that Geological Activities is located in the coastal area and is usually Lake formation is frequently attributed to bordered by the sea through a bar or a barrier geological forces. For example, tectonic island. Waves and tides encroach the sand motions can produce depressions that and pile it up to form a barrier where water is eventually fill with water to form tectonic trapped in the lagoon behind it. These water lakes. When volcanic craters fill with water, bodies may contain both freshwater and salt crater lakes may emerge as a result of water, or a combination of the two, which is volcanic activity. Furthermore, basins that referred to as brackish water. later develop into glacial lakes are carved out Process of geological work of Lakes by glacial movements during ice ages. These 1.​ A lake starts when a basin or depression is geological processes are essential to the early formed on the Earth’s crust through development of lakes. factors like erosion movement due to Geography tectonic activity, volcanic activities, or The size, water levels, and seasonal dynamics impacts of meteorite. of lakes are all influenced by the climate. Lakes may have an abundance of water in areas with heavy rainfall, but evaporation may richness of the lake. Additionally, plants are outweigh water inflow in drier places, causing involved in the creation of oxygen, the cycling lakes to diminish. Changes in temperature of nutrients, and the purifying of water. have an effect on lakes' thermal stratification, Around a lake, forests or wetlands can serve which alters the ecological balance of the as a buffer, removing sediments and lakes. The environment of the lake may be pollutants before they reach the lake. impacted by seasonal variations in water Human Activities levels, such as the melting of snow in the Lakes are greatly impacted by human activity, spring which frequently has both beneficial and bad Water Sources effects. Artificial lakes made possible by dam In order to preserve a lake's water balance, the building can supply water for recreational sources of water that feed into it are essential. purposes, hydropower, and irrigation. Rivers, precipitation, groundwater, and the However, pollution and habitat degradation melting of snow or ice are some of the ways brought on by development and that lakes can get water. The lake's hydrology industrialization can have a negative impact and water quality depend on the quantity and on lake ecosystems. The natural equilibrium quality of various water sources. For example, of the lake may be impacted if water levels are rivers contribute nutrients and sediments to lowered due to excessive extraction for lakes, which impacts their biological health, household and agricultural use. while groundwater inputs can change the Cause & impact of geological work of lakes chemical makeup and salinity of lakes Every component contributes to the dynamic Topography aspect of a lake in a different way. A lake's features are greatly influenced by the Comprehending these variables helps in the topography around it. The way water enters preservation and sustainable administration and exits the lake is determined by the of lakes, guaranteeing their ecological topography. While level locations may well-being and what benefits they offer to encourage slower water movement and both the natural world and human civilization. sedimentation, steeply sloping catchment In conclusion, lakes are important to the areas may contribute to rapid water flow and environmental and ecological processes of sediment deposition in the lake. The lake's Earth and are created by a variety of natural depth, shape, and shoreline complexity are all and man-made activities. Freshwater influenced by the topography reservoirs, climate regulation, nitrogen Soil and Rock Type cycling, carbon sequestration, and Water quality and retention are influenced by groundwater recharge are some of their the kinds of rocks and soil in the lake basin. functions. But lakes also suffer environmental Whereas impermeable materials retain water, problems like pollution and invasive species, keeping levels higher, permeable rocks and which call for careful conservation and soils let water seep through, lowering water management measures. Appreciating lakes' levels. The chemical characteristics of the lake, significance and guaranteeing their survival including its pH, nutrient levels, and general for future generations require an water quality, can be influenced by the understanding of their sources and effects. mineral makeup of the surrounding geology. River Vegetation An extensive, organic water flow. Every Lake ecosystems are significantly impacted continent and almost every type of area has by aquatic plants and adjacent vegetation. rivers. It might stretch across a large portion Fish and other aquatic life find a home in of a continent or only a few km. aquatic vegetation, which enhances the Factors Climate Vegetation Soil Processes Erosion Transportation Deposition Glacier A glacier is a massive ice sheet that moves due to its weight and due to the force of gravity. It forms when layers of snow build up and compress to create ice. Factors Temperature Greenhouse gases Snowfall Accumulation Rate Glacial Erosion - plucking and abrasion Transportation - Glaciers transport rock and debris of all shapes and sizes Deposition - and drumlins are created from deposition Puddle A puddle is a small pool of liquid, usually water, that collects on a surface. Puddles can be found on roads, sidewalks, and other surfaces. Factors Temperature Drainage Surface type Process Erosion Transportation Deposition