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Chapter 7 metamorphic rocks
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This document summarizes key concepts from a chapter about metamorphism from the textbook Essentials of Geology. Metamorphism occurs when rocks undergo changes to their texture, mineralogy, and chemistry due to changes in temperature, pressure, and reaction with fluids. There are several processes involved, and metamorphic rocks exhibit distinctive properties based on the conditions they form under. Different metamorphic environments and intensities can produce different rock types. Index minerals are used to determine metamorphic grade.Study of deform rocks, folds and its types
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1. Wall rock alteration occurs when hot hydrothermal fluids interact with surrounding country rocks, changing their mineralogy. There are two main types: hypogene alteration from ascending fluids and supergene alteration from descending waters.
2. Alteration products depend on the rock character, fluid properties like pH and temperature/pressure conditions. Important reactions include hydrolysis, hydration, dechlorination, silication, and decarbonation.
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Metamorphic petrology
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The document discusses metamorphic petrology, including the processes, conditions, and products of metamorphism. It defines metamorphism as the mineralogical and textural changes rocks undergo in the solid state due to changes in physical and chemical conditions. Metamorphic conditions include temperature, pressure, and fluid compositions. The document also describes the goals of metamorphic petrology in determining the setting, protolith, grade, and conditions of metamorphism through mineral assemblages and textures. Finally, it discusses metamorphic facies and indexes that help characterize metamorphic grade based on characteristic mineral assemblages.Structures, Uses, and Studies about Metamorphic Rocks
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This presentation present the structures and study of metamorphic rocks in which how they are useful in the field of engineering ang in daily lives.FOLIATION AND LINEATION.pptx
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- Foliations are planar fabrics in rocks that form sheets or layers. They include bedding, cleavage, schistosity, and gneissosity.
- Lineations are linear structural features in rocks that result from the parallel alignment of elongate minerals, fossils, or other linear features. They include stretched pebbles, intersection lineations, and slickensides.
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The document describes eight common igneous rock structures: vesicular, amygdaloidal, block lava, ropy lava, pillow lava, jointing and sheet structure, columnar structure, pegmatites, spherulitic, and orbicular. It was authored by Md. Yousuf Gazi, a lecturer in the Department of Geology at the University of Dhaka.Structural Geology Folds
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Structural geology is the study of rock structures and deformations within the Earth's crust. There are several types of rock structures that provide evidence of past deformation, including folds, faults, joints, and foliations. Folds occur when rock layers are bent, and there are different types such as anticlines, synclines, tight folds, overfolds, recumbent folds, and nappe folds. Understanding rock structures provides insight into the stress fields and tectonic processes that shaped the geological past.Karst Topography.pptx
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Karst topography refers to landscapes formed by the dissolution of soluble rocks like limestone and dolostone by groundwater. It is characterized by features like sinkholes, caves, underground streams, and disappearing streams. Karst landscapes are widespread globally in areas underlain by carbonate rocks, including regions in the United States, Europe, Asia, Australia, and Cuba. The development of karst topography depends on factors like the lithology of soluble bedrock, structure of the bedrock like joints and fractures, climate, hydrogeology, and time.Chapter-6 Geol 2031 Optical Mineralogy.pptx
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This document provides an overview of optical mineralogy and outlines topics to be covered in the chapter, including light properties, examining crystals under plane-polarized light and crossed polars, and refractive index determination. Key concepts are isotropic and anisotropic crystals, uniaxial and biaxial indicators, and examining crystals under convergent light. Objectives are to understand light properties and examination of minerals under different light conditions. Key examination techniques are described for isotropic, uniaxial, and biaxial crystals.
Presentation On Ophiolites
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Ophiolites are fragments of oceanic crust and upper mantle that have been uplifted and emplaced on continental margins. They consist of five main layers: sediment, pillow basalt, sheeted dikes, gabbro, and peridotite. Ophiolites provide evidence for seafloor spreading and plate tectonics. While similar in composition, ophiolites differ from oceanic crust in thickness, age, density, and composition due to uplift and emplacement processes. Ophiolites in Pakistan are found in collision zones from the Indian plate colliding with the Eurasian and Afghan plates.Igneous rocks
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There are three main types of rocks classified by how they are formed. Igneous rocks form from melted rock and can be either extrusive or intrusive. Extrusive igneous rocks cool quickly on the surface to form fine crystals like basalt and obsidian, while intrusive igneous rocks cool slowly inside the Earth to form larger crystals such as granite and gabbro. The size of crystals in igneous rocks depends on whether they cool quickly on the surface or slowly underground. deformation 
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This chapter discusses deformation of rocks through folding and fracturing. It begins by explaining that deformation occurs near plate boundaries and allows reconstruction of geologic history. The chapter then outlines topics including the plate tectonic forces that cause deformation, techniques for mapping geologic structures, how rocks deform under different conditions, basic deformation structures like faults and folds, and unraveling geologic history through successive deformation events. Key concepts are defined like brittle and ductile rock behavior, strike, dip, faults, folds, and geologic mapping tools.Economic geology - Metallogeny and plate tectonics
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1. The document discusses the relationship between plate tectonics and metal deposits. It describes various tectonic settings associated with divergent and convergent plate boundaries that are favorable for forming different types of metal deposits.
2. Key settings discussed include continental rifts, failed rift arms, passive continental margins during seafloor spreading, mid-ocean ridges, and subduction zones. Metallogeny in these settings includes deposits forming from hydrothermal vents, volcanic-hosted massive sulfides, and porphyry copper deposits.
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Igneous structure and genesis (structural geology)
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This presentation summarizes igneous rock structures formed from the cooling and solidification of magma. It describes both intrusive and extrusive igneous rock structures. Intrusive structures include concordant structures like laccoliths, lopoliths, sills, and discordant structures like batholiths, stocks, dikes, and volcanic necks. Extrusive structures include primary structures like pillow structures, lava flow structures, vesicular structures, and columnar structures. The presentation provides examples and diagrams to illustrate different igneous rock formations and the geological processes that create their characteristic shapes and features.Classification of Igneous rocks
Classification of Igneous rocksTim Corner
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This document summarizes how rocks are classified based on their formation. There are three main classes of rocks: igneous, sedimentary, and metamorphic. Within each class, rocks can be further classified based on their composition, texture, and grain size. Igneous rocks form from cooled lava or magma, and can be intrusive or extrusive based on where they solidify underground or above ground, affecting their grain size. Sedimentary rocks form from cemented sediments like grains, shells, and fossils. Metamorphic rocks have foliated or non-foliated textures indicating the process that altered the original rock.Rocks - Igneous
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Igneous rocks form when magma or lava cools and hardens. They are classified based on where they form, their texture, and composition. Igneous rocks that form inside Earth's interior through slow cooling are intrusive with coarse textures, while those forming outside through rapid cooling are extrusive with fine or glassy textures. The rate of cooling influences crystal size, with slow cooling leading to large crystals and fast cooling resulting in small or no crystals.Forms of uniaxial interference figures
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This document discusses the different forms that uniaxial interference figures can take based on the orientation of the optic axis in a mineral sample. There are three main types: 1) Optic axis figures where the optic axis is vertical and the cross pattern is centered. 2) Off-centered figures where the cross is not centered and moves as the sample is rotated. 3) Optic normal figures where the optic axis is horizontal, producing a broad, fuzzy interference pattern across most of the view. Key elements like isogyres, melatope, and isochromes are also defined. Folds
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The document discusses folds, their geometry, classification, and field study. It defines folds as bent rock layers caused by compressional forces. The geometry of folds includes limbs, hinge points, hinge lines, axial planes, axes, and other features. Folds are classified based on their shape, including anticlines, synclines, symmetrical, overturned, and others. Field study of folds involves direct observation of fold features and measuring the attitude of hinge lines and axial planes to characterize fold structures.Petrology
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Petrology is the study of rocks and their composition, texture, and structure. There are three main types of rocks: igneous rocks, which form from cooling magma; metamorphic rocks, which form from existing rocks undergoing changes due to heat, pressure, and chemical reactions; and sedimentary rocks, which form from the compaction and cementation of sediments. Igneous rocks can be categorized as extrusive or intrusive, depending on where they solidify. Common igneous rocks include granite, basalt, and syenite. Sedimentary rocks form through the weathering of existing rocks and the deposition and lithification of sediments. Texture, minerals, and formation processes help classify and identify different
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La Geología Económica implica una especial complejidad por la amalgama de conceptos científicos, tecnológicos y económicos que ella implica. De ahí los diversos enfoques con que ha sido abordada, que van desde los estrictamente científicos: ore petrology o en espa?ol: petrología de menas, que considera las menas como un caso especial de rocas, hasta los de geología económica propiamente tal, pasando por el enfoque intermedio de depósitos minerales. Este léxico está orientado hacia el enfoque intermedio, vale decir, el entendimiento de los depósitos minerales como tales. Esto es, en términos de su naturaleza y origen, y de la aplicación de esa comprensión a su explotación, así como a la exploración de nuevas reservas y nuevos yacimientos. Por otra parte, está centrado en los yacimientos metalíferos.
En este documento se presenta un léxico de términos fundamentales elaborado como material docente auxiliar para asignaturas de geología e ingeniería. Su redacción pretende ir más allá de las simples definiciones, incluyendo explicaciones básicas de cada término y su importancia y aplicaciones.
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FOLIATION AND LINEATION.pptx
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- Foliations are planar fabrics in rocks that form sheets or layers. They include bedding, cleavage, schistosity, and gneissosity.
- Lineations are linear structural features in rocks that result from the parallel alignment of elongate minerals, fossils, or other linear features. They include stretched pebbles, intersection lineations, and slickensides.
- Foliations and lineations can be primary (formed during rock formation) or secondary (formed by deformation after rock formation). Secondary fabrics provide important clues about a rock's deformation history.Structure of igneous rocks
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The document describes eight common igneous rock structures: vesicular, amygdaloidal, block lava, ropy lava, pillow lava, jointing and sheet structure, columnar structure, pegmatites, spherulitic, and orbicular. It was authored by Md. Yousuf Gazi, a lecturer in the Department of Geology at the University of Dhaka.Structural Geology Folds
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Structural geology is the study of rock structures and deformations within the Earth's crust. There are several types of rock structures that provide evidence of past deformation, including folds, faults, joints, and foliations. Folds occur when rock layers are bent, and there are different types such as anticlines, synclines, tight folds, overfolds, recumbent folds, and nappe folds. Understanding rock structures provides insight into the stress fields and tectonic processes that shaped the geological past.Karst Topography.pptx
Karst Topography.pptxDilawr
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Karst topography refers to landscapes formed by the dissolution of soluble rocks like limestone and dolostone by groundwater. It is characterized by features like sinkholes, caves, underground streams, and disappearing streams. Karst landscapes are widespread globally in areas underlain by carbonate rocks, including regions in the United States, Europe, Asia, Australia, and Cuba. The development of karst topography depends on factors like the lithology of soluble bedrock, structure of the bedrock like joints and fractures, climate, hydrogeology, and time.Chapter-6 Geol 2031 Optical Mineralogy.pptx
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This document provides an overview of optical mineralogy and outlines topics to be covered in the chapter, including light properties, examining crystals under plane-polarized light and crossed polars, and refractive index determination. Key concepts are isotropic and anisotropic crystals, uniaxial and biaxial indicators, and examining crystals under convergent light. Objectives are to understand light properties and examination of minerals under different light conditions. Key examination techniques are described for isotropic, uniaxial, and biaxial crystals.Presentation On Ophiolites
Presentation On Ophioliteshafizshahid
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Ophiolites are fragments of oceanic crust and upper mantle that have been uplifted and emplaced on continental margins. They consist of five main layers: sediment, pillow basalt, sheeted dikes, gabbro, and peridotite. Ophiolites provide evidence for seafloor spreading and plate tectonics. While similar in composition, ophiolites differ from oceanic crust in thickness, age, density, and composition due to uplift and emplacement processes. Ophiolites in Pakistan are found in collision zones from the Indian plate colliding with the Eurasian and Afghan plates.Igneous rocks
Igneous rocksMichelle Boquist
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There are three main types of rocks classified by how they are formed. Igneous rocks form from melted rock and can be either extrusive or intrusive. Extrusive igneous rocks cool quickly on the surface to form fine crystals like basalt and obsidian, while intrusive igneous rocks cool slowly inside the Earth to form larger crystals such as granite and gabbro. The size of crystals in igneous rocks depends on whether they cool quickly on the surface or slowly underground. deformation
deformation fulay
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This chapter discusses deformation of rocks through folding and fracturing. It begins by explaining that deformation occurs near plate boundaries and allows reconstruction of geologic history. The chapter then outlines topics including the plate tectonic forces that cause deformation, techniques for mapping geologic structures, how rocks deform under different conditions, basic deformation structures like faults and folds, and unraveling geologic history through successive deformation events. Key concepts are defined like brittle and ductile rock behavior, strike, dip, faults, folds, and geologic mapping tools.Economic geology - Metallogeny and plate tectonics
Economic geology - Metallogeny and plate tectonicsAbdelMonem Soltan
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1. The document discusses the relationship between plate tectonics and metal deposits. It describes various tectonic settings associated with divergent and convergent plate boundaries that are favorable for forming different types of metal deposits.
2. Key settings discussed include continental rifts, failed rift arms, passive continental margins during seafloor spreading, mid-ocean ridges, and subduction zones. Metallogeny in these settings includes deposits forming from hydrothermal vents, volcanic-hosted massive sulfides, and porphyry copper deposits.
3. The formation of different deposit types is tied to the specific geological processes associated with different stages of plate interactions, such as crustal extension during rifting and compression duringPhysical properties
Physical propertiesSatishKulkarni68
?
The document discusses various physical properties used to identify minerals, including luster, cleavage, fracture, hardness, specific gravity, and other diagnostic characteristics. It provides definitions and examples of different types of luster (metallic, sub-metallic, non-metallic), cleavage (perfect, imperfect, absent), fracture (even, uneven, hackly, conchoidal), Mohs scale of hardness (ranging from 1 to 10), approaches to measuring specific gravity, and other properties like color, streak, and reaction to acid that can aid identification. The document also includes examples of analyzing physical properties to identify mineral specimens.Igneous structure and genesis (structural geology)
Igneous structure and genesis (structural geology)Shivam Jain
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This presentation summarizes igneous rock structures formed from the cooling and solidification of magma. It describes both intrusive and extrusive igneous rock structures. Intrusive structures include concordant structures like laccoliths, lopoliths, sills, and discordant structures like batholiths, stocks, dikes, and volcanic necks. Extrusive structures include primary structures like pillow structures, lava flow structures, vesicular structures, and columnar structures. The presentation provides examples and diagrams to illustrate different igneous rock formations and the geological processes that create their characteristic shapes and features.Classification of Igneous rocks
Classification of Igneous rocksTim Corner
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This document summarizes how rocks are classified based on their formation. There are three main classes of rocks: igneous, sedimentary, and metamorphic. Within each class, rocks can be further classified based on their composition, texture, and grain size. Igneous rocks form from cooled lava or magma, and can be intrusive or extrusive based on where they solidify underground or above ground, affecting their grain size. Sedimentary rocks form from cemented sediments like grains, shells, and fossils. Metamorphic rocks have foliated or non-foliated textures indicating the process that altered the original rock.Rocks - Igneous
Rocks - Igneousdwinter1
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Igneous rocks form when magma or lava cools and hardens. They are classified based on where they form, their texture, and composition. Igneous rocks that form inside Earth's interior through slow cooling are intrusive with coarse textures, while those forming outside through rapid cooling are extrusive with fine or glassy textures. The rate of cooling influences crystal size, with slow cooling leading to large crystals and fast cooling resulting in small or no crystals.Forms of uniaxial interference figures
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This document discusses the different forms that uniaxial interference figures can take based on the orientation of the optic axis in a mineral sample. There are three main types: 1) Optic axis figures where the optic axis is vertical and the cross pattern is centered. 2) Off-centered figures where the cross is not centered and moves as the sample is rotated. 3) Optic normal figures where the optic axis is horizontal, producing a broad, fuzzy interference pattern across most of the view. Key elements like isogyres, melatope, and isochromes are also defined. Folds
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The document discusses folds, their geometry, classification, and field study. It defines folds as bent rock layers caused by compressional forces. The geometry of folds includes limbs, hinge points, hinge lines, axial planes, axes, and other features. Folds are classified based on their shape, including anticlines, synclines, symmetrical, overturned, and others. Field study of folds involves direct observation of fold features and measuring the attitude of hinge lines and axial planes to characterize fold structures.Petrology
Petrologyshruthiv19
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Petrology is the study of rocks and their composition, texture, and structure. There are three main types of rocks: igneous rocks, which form from cooling magma; metamorphic rocks, which form from existing rocks undergoing changes due to heat, pressure, and chemical reactions; and sedimentary rocks, which form from the compaction and cementation of sediments. Igneous rocks can be categorized as extrusive or intrusive, depending on where they solidify. Common igneous rocks include granite, basalt, and syenite. Sedimentary rocks form through the weathering of existing rocks and the deposition and lithification of sediments. Texture, minerals, and formation processes help classify and identify differentLéxico de geología económica - Jorge Oyarzún M., Geol. Dr. Sc. Universidad de...Alfredo Fernando Vergara Pangue
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La Geología Económica implica una especial complejidad por la amalgama de conceptos científicos, tecnológicos y económicos que ella implica. De ahí los diversos enfoques con que ha sido abordada, que van desde los estrictamente científicos: ore petrology o en espa?ol: petrología de menas, que considera las menas como un caso especial de rocas, hasta los de geología económica propiamente tal, pasando por el enfoque intermedio de depósitos minerales. Este léxico está orientado hacia el enfoque intermedio, vale decir, el entendimiento de los depósitos minerales como tales. Esto es, en términos de su naturaleza y origen, y de la aplicación de esa comprensión a su explotación, así como a la exploración de nuevas reservas y nuevos yacimientos. Por otra parte, está centrado en los yacimientos metalíferos.
En este documento se presenta un léxico de términos fundamentales elaborado como material docente auxiliar para asignaturas de geología e ingeniería. Su redacción pretende ir más allá de las simples definiciones, incluyendo explicaciones básicas de cada término y su importancia y aplicaciones.
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5 2地貌的改變與平衡
- 1. 地貌的改變與平衡 翁玉華
- 2. 改變地貌的動力—地質營力 地表趨於 平坦 加強地表起伏 對地表影響 风化 . 侵蝕 . 搬運 . 沉積 火山活動 . 造山運動 地質 作用 流水 . 冰川 . 海水 . 風 地球內部的熱能 營力 來源 外營力 內營力 營力
- 3. 地表的地質作用 氧化 —鐵與氧作用 溶解—水溶解鈉、鉀、鈣 .. 等 生物—根部酸化作用 ? 溫暖潮溼 地區為主 化學风化 分解 作用 溫差—岩石熱脹冷縮 凍裂 —水結冰 , 體積變化 生物—根部撐大作用 ? 寒冷乾燥 地區為主 物理风化 崩解 作用 岩石在原地發生破碎疏鬆、分解的作用 风化 說明 分項 定義 類別
- 4. ?
- 5. ?
- 6. 风化
- 7. ?
- 8. 风磨石 風 海蝕崖?海蝕平台?海蝕柱… .. 海浪 / 海流 U 型谷、刮痕 冰川 加深—向下侵蝕 (V 型谷 ) 加寬—側向侵蝕 加長—向源侵蝕 河流 動力作用使岩石發生破壞作用 侵蝕
- 9. ?
- 10. ?
- 11. ?
- 12. ?
- 13. ?
- 14. ?
- 15. ?
- 16. ?
- 17. ?
- 18. ?
- 19. ?
- 20. ?
- 21. ?
- 22. ?
- 23. ?
- 24. ?
- 25. ?
- 26. ?
- 27. ?
- 28. ?
- 29. 风磨石
- 30. 差異侵蝕 砂岩 抗风化侵蝕力 強 砂岩抗风化侵蝕力強 頁 岩抗风化侵蝕力 弱
- 31. 女王头
- 32. 動力最 弱 風 動力次弱 海浪 / 海流 動力最 強 冰川 產生鵝卵石 河流 风化和侵蝕後的產物搬遷至其他地方 搬運
- 33. ?
- 34. ?
- 35. ?
- 36. 沙丘 風 沙洲、沙灘 海浪 / 海流 冰磧石 冰川 平原、三角洲 河流 因動力減弱導致物質逐漸沉降下來 沉積
- 37. ?
- 38. ?
- 39. ?
- 40. ?
- 41. 冰磧石
- 42. 沙滩、沙洲
- 43. ?
- 44. 跳石海岸
- 45. ?
- 46. ?
- 47. ?
- 48. 淘選度比較 風 > 海 > 河流 > 冰川 沉積顆粒的一致性
- 49. 海平面 -- 最終侵蝕基準面 海平面以上—以侵蝕為主 海平面以下—以沉積為主 湖、水庫—暫時侵蝕基準面
- 50. 侵蝕力較強 侵蝕力較強 沉积作用為主 沉积作用為主
- 51. 人為與自然平衡 採砂石 加速上游侵蝕 ? 橋墩易裸露 , 造成橋樑失去支撐
- 52. 海岸線平衡 搬運量比較 河流 > 海流 ? 海岸線前進 河流 = 海流 ? 海岸線穩定 河流 < 海流 ? 海岸線後退 河流搬運 海流搬運
- 53. The ending…..