VOLUME I. |
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PRELIMINARY OUTLINE. |
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PAGE |
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| Astronomic Geology | ||
| The earth as a planet, 2. Its satellite, 3. Dependence on the sun, 4. Meteorites, 4. | ||
| Geognosy | 5 |
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I. |
The Atmosphere | |
| Mass and extent, 6. Geologic activity, 6. A thermal blanket, 7. | ||
II. |
The Hydrosphere | |
| Oceanic dimensions, 8. Geologic activity, 8. Chief horizons of activity, 9. | ||
III. |
The Lithosphere | |
| Irregularities, 10. Epicontinental seas, 11. Diversities of surface, 12. The surface mantle of the lithosphere, 12. The crust of the lithosphere, 13. The interior, 14. Varieties of rock in crust, 14. Stratified rocks, 14. Conformability, 15. Relative ages, 15. The crystalline rocks, 16. Four great sedimentary eras, 17. The Archean complex, 18. | ||
| General Table of Geologic Divisions | ||
THE ATMOSPHERE AS A GEOLOGICAL AGENT. |
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| The Atmosphere as a Direct Agency | ||
I. |
Mechanical Work | |
| Transportation and deposition of dust, 22. Transportation and deposition of sand, 25. Formation of dunes, 26. Shapes of dunes, 26. The topographic map, 30. Topography of dune areas, 32. Migration of dunes, 33. Distribution of dunes, 35. Wind ripples, 37. Abrasion by the wind, 38. Effects of wind on plants, 40. Indirect effects of the wind, 41. | ||
II. |
Chemical Work | |
| Precipitation from solution, 41. Oxidation, 42. Carbonation, 43. Other chemical changes, 43. Conditions favorable for chemical changes, 43. | ||
| The Atmosphere as a Conditioning Agency | ||
I. |
Temperature Effects | |
II. |
Evaporation and Precipitation | |
III. |
Effects of Electricity. | |
| Summary | ||
THE WORK OF RUNNING WATER. |
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| Rain and River Erosion | ||
| Subaërial Erosion without Valleys | ||
| The Development of Valleys | ||
| By the growth of gullies, 63. Limits of growth, 67. The permanent stream, 70. Other modes of valley development, 73. Structural valleys, 77. The courses of valleys, 77. The development of tributaries, 78. | ||
| A Cycle of Erosion. Its Stages | ||
| General Characteristics of Topography Developed by River Erosion | ||
| Special Features Resulting from Special Conditions of Erosion | ||
| Bad-land topography, 93. Special forms of valleys; canyons, 94. | ||
| The Struggle for Existence Among Valleys and Streams | ||
| Piracy, 103. | ||
| Rate of Degradation | ||
| Material in solution in river water. 107. | ||
| Economic Considerations | ||
| Analysis of Erosion | ||
| Weathering | ||
| Transportation | ||
| Transporting power and velocity, 115. How sediment is carried, 116. | ||
| Corrasion | ||
| Abrasion, 119. Solution, 122. | ||
| Conditions Affecting the Rate of Erosion | ||
| The Influence of Declivity | ||
| The Influence of Rock | ||
| Physical constitution, 124. Chemical composition, 124. Structure, 125. | ||
| The Influence of Climate | ||
| Effects of Unequal Hardness | ||
| Rapids and falls, 132. Rock terraces, 140. Narrows, 141. Other effects on topography, 142. Adjustment of streams to rock structures, 146. | ||
| Influence of Joints and Folds | ||
| Joints, 150. Folds, 154. | ||
| Effect of Changes of Level | ||
| Rise, 161. Sinking, 170. Differential movement, warping, 171. | ||
| The Aggradational Work of Running Water | ||
| Principles involved, 177. | ||
| The Deposits | ||
| Types, 181. Alluvial fans and cones, 181. Ill-defined alluvium, 183. Alluvial plains, 184. Flood-plains due to alluviation, 186. Flood-plains due to obstructions, 188. Levees, 188. Flood-plain meanders, cut-and-fill, 190. Scour-and-fill, 194. Materials of the flood-plain, 196. Topography of the flood-plain, 196. Topographic adjustment of tributaries, 197. River-lakes, 198. Deltas, 198. Delta lakes, 204. | ||
| Stream Terraces | ||
| Due to inequalities of hardness, 204. Normal flood-plain terraces, 205. Flood-plain terraces due to other causes, 208. Discontinuity of terraces, 209. Termini of terraces, 210. | ||
THE WORK OF GROUND (UNDERGROUND) WATER. |
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| Conditions influencing descent of rain-water, 213. Supply of ground-water not altogether dependent on local rainfall, 215. Ground-water surface—water table, 215. Depth to which ground-water sinks, 216. Movement of ground-water, 220. Amount of ground-water, 221. Fate of ground-water, 221. | ||
| The Work of Ground-water | ||
| Chemical Work | ||
| Quantitative importance of solution, 223. Deposition of mineral matter from solution, 225. | ||
| Mechanical Work | ||
| Results of the Work of Ground-water | ||
| Weathering, 226. Caverns, 227. Creep, slumps, and landslides, 231. | ||
| Summary | ||
| Springs and Flowing Wells | ||
| Mineral matter in solution, 235. Geysers, 236. Artesian wells, 242. | ||
THE WORK OF SNOW AND ICE. |
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| Snow- and Ice-fields | ||
| The passage of snow into névé and ice, 246. Structure of the ice, 247. Texture, 247. Inauguration of movement, 248. | ||
| Types of Glaciers | ||
| The General Phenomena of Glaciers | ||
| Dimensions, 256. Limits, 258. Movement, 259. Conditions affecting rate of movement, 261. Likenesses and unlikenesses of glaciers and rivers, 262. | ||
| Surface Features | ||
| Topography, 266. Surface moraines, 266. Relief due to surface débris, 268. Dust-wells, 269. Débris below the surface, 272. | ||
| Temperature, Waste, and Drainage | ||
| The winter wave, 274. The summer wave, 276. The temperature of the bottom, 276. Temperature of the interior of the ice, 277. Compression and friction as causes of heat, 278. Summary, 279. Movement under low temperature, 279. Evaporation, 279. Drainage, 280. | ||
| The Work of Glaciers | ||
| Erosion and Transportation | ||
| Getting load, 282. Conditions influencing rate of erosion, 283. Summary, 286. Varied nature of glacial débris, 286. The topographic effects of glacial erosion, 287. Fiords, 290. The positions in which débris is carried, 290. Transfers of load, 292. Wear of drift in transit, 298. | ||
| Deposition of the Drift | ||
| Beneath the body of the ice, 298. At ends and edges of glaciers, 299. | ||
| Types of Moraines | ||
| The terminal moraine, 301. The ground moraine, 301. The lateral moraines, 302. Distinctive nature of glacial deposits, 304. Glaciated rock surfaces, 304. | ||
| Glacio-Fluvial Work | ||
| Icebergs | ||
| The Intimate Structure and the Movement of Glaciers | ||
| The growth and constitution of a glacier, 308. The arrangement of the crystal axes, 312. | ||
| The Probable Fundamental Element in Glacial Motion | ||
| Melting and freezing, 313. Accumulated motion in the terminal part of a glacier, 316. | ||
| Auxiliary Elements | ||
| Shearing, 317. High temperature and water, 318. Applications, 319. | ||
| Corroborative Phenomena | ||
| Other Views of Glacier Motion | ||
THE WORK OF THE OCEAN. |
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| Volume and composition, 324. Topography of bed, 326. Distribution of marine life, 328. | ||
| Processes in Operation in the Sea | ||
| Diastrophism, 329. Vulcanism, 332. Gradation, 333. | ||
| Movements of the Sea-water | ||
| Differences in density and their results, 335. Differences in level and their results. 335. Movements generated by winds, 336. Movements generated by attraction, 322. Aperiodic movements, 338. Summary, 339. | ||
| Waves | ||
| Wave-motion, 339. | ||
| Work of the Waves | ||
| Erosion | ||
| By waves and undertow, 342. | ||
| Topographic Features Developed by Wave Erosion | ||
| The sea-cliff, 349. Chimney rocks, etc., 350. Sea caves, 350. The wave-cut terrace, 351. Wave erosion and horizontal configuration, 353. | ||
| Transportation by Waves | ||
| Deposition by Waves, Undertow, and Shore Currents | ||
| The beach, 355. The barrier, 356. The spit, the bar, and the loop, 357. Wave-built terraces, 363. | ||
| Effect of Shore Deposition on Coastal Configuration | ||
| Summary of Coastal Irregularities | ||
| The Work of Ocean-currents | ||
| Deposits of the Ocean-bed | ||
| Shallow-water Deposits | ||
| Littoral deposits, 369. Non-littoral, mechanical deposits in shallow water, 369. Characteristics of shallow-water deposits, 373. Topography of shallow-water deposits, 374. Chemical and organic deposits, 375. Limestone, 378. | ||
| Deep-sea Deposits | ||
| Contrasted with shallow-water deposits, 378. Sources, 380. Mechanical inorganic deposits, 380. Organic constituents of pelagic deposits, 382. Chemical deposits, 383. | ||
| Lakes | ||
| Changes taking place in lakes, 387. Lacustrine deposits, 388. Extinct lakes, 388. Lake ice, 389. Saline lakes, 391. Indirect effects of lakes, 392. Composition of lake waters, 392. | ||
THE ORIGIN AND DESCENT OF ROCKS. |
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| Composition of Igneous Rocks | ||
| Leading elements, 396. Union of elements, 397. Formation of minerals, 397. Sources of complexity, 398. The leading minerals of igneous rocks, 399. The feldspathic minerals, 400. The ferromagnesian minerals, 400. Summary of salient facts, 401. | ||
| The Nature of Molten Magmas | ||
| Time required in crystallization, 402. Successive stages of crystallization, 403. | ||
| The Fragmental Products of Sudden Cooling | ||
| Pyroclastic rocks, 404. | ||
| The Glassy Rocks | ||
| The solid glasses. 406. The first stages of crystallization, 407. The obsidians, 407. | ||
| Special Structures | ||
| Flow structure, 410. Amygdaloids, 411. | ||
| The Porphyritic Rocks | ||
| The Phanerocrystalline Rocks | ||
| The phanerites, 412. The granites, 413. The syenites, 415. The diorites, 416. The gabbros, 416. The peridotites, 416. The basalts, 417. The dolerites, 417. General names, 418. | ||
| Derivation of Secondary Rocks | ||
| Regolith, 422. Disrupted products: arkose and wacke, 422. Disintegrated products, 422. | ||
| Classes of Sedimentary Rocks | ||
| Shales, sandstones, and conglomerates, 422. Limestones and dolomites, 424. Precipitates, 424. Iron-ore beds, 425. Silicious deposits, 425. Organic rocks, 426. | ||
| Internal Alterations of Rocks | ||
| Oxidation and deoxidation, 427. Solution and deposition, 427. Hydration and dehydration, 428. Carbonation and decarbonation, 429. Molecular rearrangements, 431. | ||
| The Salient Features of Rock Descent | ||
| The Reascensional Process | ||
| Induration under ordinary pressures and temperatures, 432. Cavity filling, 436. Fissure filling; veins, 437. Solution as well as deposition, 437. Concretions, 438. Replacements and pseudomorphs, 439. Incipient crystallization, 439. | ||
| Reconstruction under Exceptional Conditions | ||
| Slaty structure, 441. Foliation, schistosity, 443. Metamorphism by heat, 446. Metamorphism by heat and lateral pressure, 448. Deep-seated metamorphism, 449. Completion of the rock cycle, 449. | ||
| Various Classifications and Nomenclatures | ||
| New System of Classification and Nomenclature | ||
| The Proposed Field System | ||
| The phanerites, 451. The aphanites, 452. | ||
| The Proposed Quantitative System | ||
| Reference List of the More Common Minerals | ||
| Reference List of the More Common Rocks | ||
| Ore Deposits | ||
| Concentration, 474. Exceptional and doubtful cases, 474. Original distribution, 475. Magmatic segregation, 475. Marine segregation and dispersion, 476. Origin of ore regions, 477. Surface residual concentration, 478. Purification and concentration, 478. Concentration by solution and reprecipitation, 479. Location of greatest solvent action, 480. Short-course action, 481. Long-course action, 481. Summary, 483. The influence of contacts, 484. The effect of igneous intrusions, 484. The influence of rock walls, 484. | ||
STRUCTURAL (GEOTECTONIC) GEOLOGY. |
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| The structural phases which rocks assume, 486. | ||
| Structural Features of Sedimentary Rocks | ||
| Stratification, 486. Lateral graduation, 488. Special markings, 489. Concretionary structure, 490. Secretions, 497. | ||
| Structural Features of Igneous Rocks | ||
| Structural Features Arising From Disturbance | ||
| Inclination and folding of strata, 500. Joints, 510. Sandstone dikes, 514. Faults, 514. The significance of faults, 521. Effect of faulting on outcrops, 522. | ||
THE MOVEMENTS AND DEFORMATIONS OF THE EARTH’S BODY (DIASTROPHISM). |
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| Minute and Rapid Movements | ||
| Earthquakes | ||
| Points of origin, foci, 527. The amplitude of the vibrations, 529. Destructive effects, 530. Direction of throw, 531. Rate of propagation, 532. Sequences of vibrations, 533. Gaseous emanations, 533. Distribution of earthquakes, 533. | ||
| The Geologic Effects of Earthquakes | ||
| Fracturing of rock, 534. Changes of surface, 534. Effects on drainage, 535. Effects on standing water, 535. Changes of level, 536. | ||
| Slow Massive Movements | ||
| Present movements, 538. Fundamental conceptions, 539. | ||
| Nearly Constant Small Movements | ||
| Reciprocal features, 541. | ||
| The Great Periodic Movements | ||
| Mountain-forming movements, 542. Distribution of folded ranges, 543. Plateau-forming movements, 543. Continent-forming movements, 544. Relations of these movements in time, 545. Relations of vertical to horizontal movements, 545. The squeezed segments, 546. The depressed or master segments, 546. The differential extent of crustal movements, 548. | ||
| The Causes of Movement | ||
| General Considerations | ||
| 1. The centripetal agencies | ||
| Gravity, 552. Molecular and sub-molecular attractions, 554. Cohesion and crystallization, 554. Diffusion, 555. Chemical combination, 556. Sub-atomic forces 556. | ||
| 2. The resisting agencies | ||
| Heat, 557. All resistance perhaps due to motion, 558. | ||
| Alternative Views of Original Heat Distribution | ||
| Thermal distribution on the convection hypothesis, 559. Level of no stress, 561. Thermal distribution on the hypothesis of central solidification, 562. Thermal distribution under the accretion hypothesis, 564. | ||
| Computed Pressures, Densities, and Temperatures within the Earth Based on Laplace’s Law | ||
| Recombination of material, 568. Comparison of the hypotheses, 568. | ||
| Observed Temperatures in Excavations | ||
| Explanations of varying increment, 570. The permeation and circulation of water, 570. Chemical action, 570. Differences in the conductivity of rock, 571. Compression, 571. Gradients projected, 571. The amount of loss of heat, 572. The amount of shrinkage from loss of heat, 572. | ||
| Other Sources of Deformation | ||
| Transfer of internal heat, 574. Denser aggregation of matter, 574. Extravasation of lavas, 574. Change in the rate of rotation, 575. Distribution of rigidity, 578. | ||
| Sphericity as a Factor in Deformation | ||
| The influence of the domed form of the surface, 581. Theoretical strength of domes of earth-dimensions, 581. Stress-accumulation independent of sphericity, 583. The actual configuration of the surface, 584. Concave tracts, 584. General conclusion, 588. | ||
THE EXTRUSIVE PROCESSES. |
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| Outward movements, 590. | ||
| Vulcanism | ||
| Phases of vulcanism, 591. | ||
| 1. Intrusions | ||
| The heating action, 592. | ||
| 2. Extrusions | ||
| Fissure eruptions, 593. Volcanic eruptions, 594. Intermediate phenomena, 596. Lunar craters, 598. | ||
| Volcanoes | ||
| Number of, 599. | ||
| Distribution of Volcanoes | ||
| In time, 599. Relative to land and sea, 599. Relative to crustal deformations, 601. In latitude, 603. In curved lines, 603. | ||
| Relations of Volcanoes | ||
| Relations to rising and sinking surfaces, 604. Relations to one another, 605. Unimportant coincidences, 606. Periodicity, 607. | ||
| Formation of Cones | ||
| Lava-cones, 608. Cinder-cones, 608. Subordinate cones, 610. Composite cones, 610. Extra-cone distribution, 610. | ||
| Lavas | ||
| Their nature, 612. Consanguinity and succession of lavas, 614. Temperature of lavas, 615. Depth of source, 616. | ||
| Volcanic Gases | ||
| Differences in gas action, 617. Spasmodic action, 618. Kinds of gases, 618. Residual gases in volcanic rock, 619. The source of the gases, 621. | ||
| The Cause of Vulcanism | ||
| I. On the Assumption that the Lavas are Original | ||
| Lava outflows from a molten interior, 624. Lavas assigned to molten reservoirs, 624. | ||
| II. On the Assumption that the Lavas are Secondary | ||
| Lavas assigned to the reaction of water and air penetrating to hot rocks, 625. Lavas assigned to relief of pressure, 627. Lavas assigned to melting by crushing, 628. Lavas assigned to melting by depression, 629. Vulcanism assigned to the outflow of deep-seated heat, 629. | ||
| Modes of Reaching the Surface | ||
| Additional Considerations Relative to the Gases | ||
| Thermal Considerations | ||
THE GEOLOGIC FUNCTIONS OF LIFE. |
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| I. The Distinctive Features of Organic Processes | ||
| The Chemical Work of Life | ||
| Life material chiefly atmospheric, 638. The non-atmospheric factors, 639. | ||
| (1) Changes in the composition of the atmosphere | ||
| The consumption and restoration of carbon dioxide, 640. The freezing and consumption of oxygen, 640. The organic residue, 640. The meaning of the organic residue, 641. The more inert factor, 642. Probable fluctuations of atmospheric composition, 642. The climatic effects of organic action, 643. | ||
| (2) Aid and hindrance to inorganic action | ||
| The promotion of disintegration, 644. Protection against erosion, 644. The influence of land vegetation on the character of the sediments, 645. | ||
| (3) Distinctive deposits | ||
| Organic rocks, 646. Inorganic rocks due to life, 646. | ||
| Fossils | ||
| The general order of life succession determined by stratigraphy, 647. Fossils as means of correlation, 647. | ||
| Special Modes of Aggregation and of Movement | ||
| The Mental Element | ||
| (1) The material effects of the mental element, 649. Human modification of the animal and vegetal kingdoms, 650. (2) The psychological factors as such, 651. | ||
| II. Special Contributions of the Organic Kingdoms | ||
| Contributions of the Plant Kingdom | ||
| Reference table of the principal groups of plants, 653. The contribution of the Thallophytes, 653. The contribution of the Bryophytes, 656. The contribution of the Pteridophytes, 657. The contribution of the Spermatophytes, 657. Plant life terrestrial rather than marine, 658. | ||
| Contributions of the Animal Kingdom | ||
| Reference table of the principal groups of animals, 659. The contribution of the Protozoa, 660. The contribution of the Cœlenterata, 661. The contribution of the Echinodermata, 661. The contribution of the Vermes, 662. The contribution of the Molluscoidea, 662. The contribution of the Mollusca, 662. The contribution of the Arthropoda, 662. The contribution of the Vertebrata, 663. | ||
| III. The Associations and Ecological Relations of Life | ||
| The Basis of Floras and Faunas | ||
| Assemblages Influenced by the Mutual Relations of Organisms | ||
| Food relations, 664. Adaptive relations, 665. Competitive relations, 665. Offensive and defensive relations, 665. Implied forms of life, 666. | ||
| Assemblages Influenced by Environment | ||
| Plant societies, 667. | ||
| The Influence of Geographic Conditions on the Evolution of Floras and Faunas | ||
| The development of provincial and cosmopolitan faunas, 668. Restrictive and expansional evolution, 672. | ||