Strength and Structure of the Earth2025|PDF|Epub|mobi|kindle电子书版本百度云盘下载

Strength and Structure of the EarthPDF格式电子书版下载

注意：本站所有压缩包均有解压码： 点击下载压缩包解压工具

1. INTRODUCTORY1

The Problem1

Vocabulary5

Discontinuities in the Earth16

Calculated Internal Densities21

Figure of the Earth; Geoid, Ellipsoid, Spheroid24

2. DEVELOPMENT OF THE IDEA OF ISOSTASY36

Bouguer to Petit36

Pr38

Airy42

Hall50

Jamieson50

Dutton51

Gilbert53

Helmert ; Schweydar54

Suggestions Regarding Isostatic Compensation56

3. TESTING ISOSTASY WITH THE PLUMB-LINE65

Deflections of the Vertical65

Hayford's First Investigation67

Topographic Deflections70

Construction of the Geoid78

Recognition of Isostasy81

Effect of Isostatic Compensation on the Direction of the Vertical87

Statistical Tests of Conclusions94

Degree of Isostatic Compensation99

Amended Ellipsoid of Reference102

Hayford's Second Investigation102

Conclusions Regarding the Dimensions of Uncompensated Loads104

4. MEASUREMENT OF GRAVITY; COMPARISON OF INTENSITIES106

Gravitation106

Relation of Gravity to Latitude109

Measurement of Gravity111

Reduction of Values of Gravity114

Free-air Reduction114

Bouguer Reduction116

Isostatic Reductions120

Indirect Reduction126

Clearing-house for Systematic Record of Anomalies129

5. GRAVIMETRIC TESTS OF ISOSTASY IN THE UNITED STATES, BY HAYFORD AND BOWIE131

Introduction131

Assumed Conditions for Isostatic Compensation132

Theoretical Gravity at a Station139

Correction for Elevation139

Correction for the Effects of Topography and Compensation140

Specimen Isostatic Anomalies149

Comparison with the Corresponding Free-air and Bouguer Anomalies149

Local Versus Regional Compensation152

Relation of Anomaly to Varying Depth of Compensation154

Anomalies in Terms of Masses154

General Conclusions156

6. LATER GRAVIMETRIC TESTS OF ISOSTASY IN NORTH AMERICA159

Bowie Report of 1912159

Bowie Report of 1917161

Bowie Report of 1924174

United States Values of Gravity Reported Since 1924182

Putnam's Discussion of United States Data184

Gilbert's Estimate of Uncompensated Loads187

Heiskanen on Gravity in the United States187

Gravity in Canada190

Concluding Remarks191

7. TESTING ISOSTASY IN EUROPE196

Introduction196

Gravity in Alps and Apennines197

Heiskanen's Studies205

Caucasus205

Norway208

Gravity in Finland210

Gravity Measurements in Cyprus211

Additional European Data213

Review and Forecast215

8. TESTING ISOSTASY IN AFRICA AND ASIA218

Earlier Work in East Africa218

Bullard on Gravity in East Africa219

Gravity in Siberia224

Conditions in India224

The Geoid in India225

Gravity Anomalies in India236

Observations in Turkestan247

Gravity Anomalies in Japan248

Some Leading Results250

9. TESTING ISOSTASY AT SEA252

Introduction252

Observations of Hansen, Schi?tz, and Hecker253

Measurement of Gravity at Sea, by Vening Meinesz256

Mean Gravity Anomalies Over the Open Ocean259

Gravity Anomalies Over Mediterranean Seas264

Strip of Negative Anomalies, East Indies269

Negative Strip of the West Indies285

Anomalies Over Ocean Deeps Facing Mountainarcs290

Gravity Profiles off Shores294

Gravity Anomalies in the Vicinity of Volcanic Islands298

Gravity Anomalies at Stations Near Great Deltas303

Conclusions305

10. NATURE'S EXPERIMENTS WITH ICECAPS309

Introduction309

Jamieson Hypothesis310

Warping of Fennoscandia, Past and Present312

Objections to Jamieson's Isostatic Hypothesis316

Recoil of the Glaciated Tract of Northeastern North America326

Nansen's Evidence from the Strandflat330

Summary334

11. RETROSPECT337

Introduction337

Meaning of the Word "Isostasy"338

Proofs of Close Approach of the Earth to Ideal Isostasy342

Relation of Gravity Anomaly to Spheroid of Reference344

Need of Great Extension of the Gravitational Survey345

Effect of Errors of Mensuration and Computation348

Effect of Changing the Assumed Type of Isostatic Compensation349

Effect of Changing the Assumed Depth of Compensation350

Effect of Local Abnormalities of Density of Rock351

How Permanent are Areas of One-sign Anomaly?351

12. STRENGTH OF THE EARTH-SHELLS353

Introduction353

Stresses Caused by Departures from Isostasy355

Dimensions of Stable Areas of One-sign Anomaly361

Anomaly Areas in the United States362

Mechanical Conditions in Peninsular India364

Anomaly Field Along the Pacific Coast of North America369

Anomaly Field of the Eastern Atlantic and Adjacent Land371

Anomaly Field of the Western Pacific373

Summary373

Anomaly Fields of the Mediterranean Seas373

Anomaly Fields of the Open-ocean "Deeps"376

Anomaly Fields Surrounding Volcanic Islands379

Comparison of Loads on Continental and Oceanic Sectors; Strength of the Lithosphere380

Experiments on the Relation of High Confining Pressure to the Strength of Rock384

The Unstable Glaciated Tracts385

Comparison of Conditions in India and Fennoscandia390

Horizontal Variation of Thickness of the Lithosphere393

Strength of the Lithosphere at Earlier Geological Epochs396

The Asthenosphere and Theories of Diastrophism and Petrogenesis398

The Asthenosphere and Deep-focus Earthquakes400

The Asthenosphere and Warped Peneplains407

Strength of the Mesospheric Shell408

Conclusions410

INDEX419