The Earth's Crust

Geophysical Monograph Series American Geophysical Union......Page 1
Geophysical Monograph Series......Page 2
The Earth\'s Crust......Page 3
The Earth\'s Crust......Page 4
Copyright......Page 5
FOREWORD......Page 6
ACKNOWLEDGEMENTS......Page 8
CONTENTS......Page 9
The Crustal Setting of Sedimentary Basins......Page 12
Cycle of Crustal Evolution......Page 13
Models of Oceanic Crustal Thickening......Page 14
Models for the Development of \'Continental\' Crust......Page 17
Models of Crustal Thinning......Page 19
Examples of Transitional Crustal Types......Page 23
References......Page 27
Introduction......Page 29
Geologic Setting......Page 31
Garnet Granulites......Page 33
Mafic Granulites: Two-Pyroxene Gr.anulite, Charnockite, and Anorthosite......Page 39
Discussion......Page 43
Conclusions and Inferences......Page 60
References......Page 61
Introduction......Page 66
Relationship of Basaltic Volcanism to Silicic Magma Chambers......Page 67
Petrologic Evidence of Interaction of Basalt and Rhyolite Magmas......Page 68
Thoroughness of Mixing and Evidence of Partially Mixed Magma Bodies......Page 74
Statement of Model......Page 77
Isotopic Data and Inferences Concerning the Rhyolite Source Region......Page 78
REFERENCES......Page 83
SIGNIFICANCE OF FE-MG CORDIERITE STABILITY RELATIONS ON TEMPERATURE, PRESSURE, AND WATER PRESSURE IN CORDIERITE GRANULITES......Page 87
Previous Results......Page 88
Experimental and Calculated Results......Page 91
General Considerations......Page 96
Conclusions......Page 99
Notation......Page 100
References......Page 101
Introduction......Page 103
The Samples......Page 105
Differential Strain Analysis......Page 106
Velocities of Elastic Waves......Page 108
Electrical Resistivity......Page 109
Differential Strain Analysis......Page 111
Error Analysis......Page 113
Resistivity......Page 117
Conclusions......Page 121
References......Page 123
Introduction......Page 126
Characterizing of Velocity-Pressure Functions......Page 127
Groups......Page 128
Trends......Page 130
Characterizing Parameters......Page 131
Theoretical Functions......Page 134
Interpretation and Modeling......Page 143
Conclusions......Page 148
Appendix: Summary of Descriptions......Page 152
References......Page 154
Introduction......Page 156
The Samples......Page 157
Granitic Rocks......Page 160
Mafic Rocks......Page 176
Volcanic Rocks......Page 182
Conclusions......Page 184
References......Page 186
Introduction......Page 188
Samples......Page 189
Electrical Measurement......Page 190
Granites......Page 192
Mellen Gabbro......Page 194
Granite......Page 196
References......Page 201
Introduction......Page 203
Experimental Approach for Laboratory Internal Friction Measurements......Page 204
Sample Preparation......Page 205
Results......Page 207
Low Frequency Apparatus......Page 208
Experiment 3: Q Measurements on Rocks under Confining Pressure......Page 211
Q of Outgassed Rock......Page 213
Discussion of Results......Page 214
References......Page 218
Introduction......Page 220
Experimental Procedure......Page 221
Velocity......Page 224
Permeability......Page 225
Discussion......Page 229
References......Page 235
Introduction......Page 237
Fracture Relationships......Page 239
Physical Properties......Page 242
Summary......Page 245
References......Page 246
Introduction......Page 247
The Method......Page 249
Some Results......Page 250
Conclusion......Page 255
References......Page 257
SEISMIC VELOCITY, REFLECTIONS, AND STRUCTURE OF THE CRYSTALLINE CRUST......Page 258
Geology......Page 259
Reflections......Page 261
Discussion......Page 270
References......Page 272
Introduction......Page 275
Method......Page 278
Comparison of Velocities......Page 280
Blake-Bahama Velocity-Depth Section......Page 288
Conclusions......Page 290
References......Page 291
A NEW MODEL OF THE CONTINENTAL CRUST......Page 293
1. Introduction......Page 294
2. Evidence for Fine Structure Within the Crust......Page 296
3. Velocity Gradient at Top of Basement......Page 299
4. Sialic Low-Velocity Zone......Page 301
5. Middle and Lower Crust......Page 305
6. Crust-Mantle Transition......Page 309
7. New Crustal Model......Page 312
References......Page 316
Introduction......Page 322
Grenville Experiment......Page 323
Yellowknife Experiment......Page 326
Cordillera Experiment......Page 330
Discussion......Page 339
Upper Crust......Page 340
Middle Crust......Page 343
Crust-Mantle Transition......Page 344
Conclusions......Page 348
References......Page 349
Introduction......Page 352
Average Seismic Properties of the Crust......Page 353
Main Features of the Structure of the Crust and the Crust-Mantle Boundary in North America......Page 355
The Crust-Mantle Boundary in Europe......Page 360
Summary and Conclusion......Page 367
References......Page 370
Data......Page 373
Data Analysis......Page 374
Conclusions......Page 380
References......Page 385
Introduction......Page 387
Geological Characteristics......Page 388
Crustal Structure......Page 390
Seismograph Stations and Records......Page 392
Amplitudes of Reflection Phases......Page 394
properties of the Discontinuity......Page 395
Extent of the Magma Body......Page 397
Depth. of the Magma Body......Page 398
Spatial Distribution of Earthquakes......Page 400
Time Distribution of Earthquakes......Page 401
Discussion......Page 403
References......Page 404
Introduction......Page 406
Attenuation Coefficient Determinations......Page 407
Inversion of Data......Page 408
North America......Page 409
Higher-Mode Attenuation......Page 410
Eurasia......Page 411
Nature of Data Available......Page 413
Averag Qβ-1 Model for the Pacific......Page 417
Eastern Pacific......Page 418
East Pacific Rise......Page 420
Conclusions......Page 421
References......Page 425
Introduction......Page 427
Model Studies......Page 428
Application to Eastern Basin and Range Province......Page 432
Discussion......Page 438
References......Page 439
Introduction......Page 440
The Problem......Page 441
Rotating Dipole Method......Page 447
Field Surveys......Page 452
Interpretation......Page 461
References......Page 468
ELECTRICAL STUDIES OF THE DEEP CRUST IN VARIOUS TECTONIC PROVINCES OF SOUTHERN AFRICA......Page 470
Introduction......Page 471
Sounding Strategy......Page 473
Tectonic Provinces of Southern Africa......Page 474
Tectonic setting.......Page 476
Electrical results......Page 477
Tectonic setting......Page 484
Electrical results.......Page 485
Tectonic setting......Page 487
Electrical results......Page 488
Discussion of Electrical Sounding Results inTerms of Crustal Structure......Page 489
Conclusions......Page 495
References......Page 497
Introduction......Page 501
Long-Range Dipole-Dipole Transmissions......Page 504
Near-Surface Characteristics of the Flambeau Anomaly......Page 508
Investigation of a Single Conductive Feature Within the Flambeau Anomaly: Hay Creek Profile......Page 510
Numerical Computations for the AMT and dc Dipole-Dipole Profiles......Page 514
Interpretation of AMT Data: Hay Creek Profile......Page 516
Interpretation of the Long-Range dc Dipole-Dipole Transmissions......Page 518
Interpretation of the Effect of Finite Length of the Flambeau Anomaly......Page 522
Other Geophysical and Geological Information and the Flambeau Anomaly......Page 524
Conclusions......Page 527
References......Page 528
Introduction......Page 531
The Inverse Problem......Page 535
Calculation of the Partial Derivatives......Page 538
Results......Page 539
Discussion......Page 545
Conclusions......Page 547
References......Page 550
Introduction......Page 553
Data Analysis......Page 554
S and H Inversion of Magnetotelluric Observations......Page 557
Interpretation......Page 566
Simplification and Consolidation of the S and H Models......Page 567
Discussion......Page 568
References......Page 572
Introduction......Page 576
California- Nevada......Page 580
Wyoming - Colorado - New Mexico......Page 582
The Midwest......Page 585
The Appalachians......Page 587
Discussion and Conclusions......Page 588
References......Page 590
Introduction......Page 593
Resistivity Network......Page 594
Instrumentation......Page 595
Data......Page 598
Experimental Errors......Page 599
Near-Surface Resistivity Variations......Page 603
Tectonic strain-resistivity variations......Page 606
Conclusions......Page 612
References......Page 613
Experimental Procedure......Page 615
Data Acquisition......Page 616
Aluminum Specimen......Page 617
Event Types......Page 618
Loading .System......Page 620
Stable Sliding to Stick-Slip Transition......Page 621
Stiffness Model......Page 622
Conclusion......Page 624
References......Page 625
HEAT FLOW IN THE UNITED STATES AND THE THERMAL REGIME OF THE CRUST......Page 626
A Heat Flow Map......Page 627
General......Page 633
Interpretation of regional heat flow in terms of crustal regime......Page 634
Heat production and conductive transients......Page 638
Convection--general considerations......Page 641
Hydrothermal systems......Page 643
Convection and Regional Heat Flow......Page 648
Sierra Nevada and Eastern United States: Effects of Radioactivity......Page 652
The Basin and Range Province: Effects of Radioactivity and Convection......Page 657
Discussion and Summary......Page 667
References......Page 671
Introduction......Page 676
Geophysics......Page 677
Discussion......Page 679
Geology......Page 680
Geophysics......Page 683
Discussion......Page 684
Raft River Geothermal System......Page 685
Geology......Page 686
Discussion......Page 687
Summary......Page 689
References......Page 690
Introduction......Page 693
Numerical Simulation of Fluid Circulation......Page 694
The Nature of Fluid Circulation Related to Thermal Anomalies......Page 695
Fluid Circulation in the Crust......Page 702
References......Page 704
Introduction......Page 705
Formulation of the Problem......Page 707
Formation of a geothermal reservoir......Page 708
Withdrawal of fluids from a geothermal reservoir......Page 709
Formation of a geothermal reservoir......Page 711
Withdrawal of fluids from a geothermal reservoir......Page 714
Numerical Results and Discussion......Page 715
Withdrawal of fluids from a geothermal reservoir......Page 716
Concluding Remarks......Page 720
References......Page 721
Introduction......Page 722
Formulation of the Problem......Page 723
Numerical Solutions......Page 725
Boundary Layer Analysis......Page 729
Capillary Model for Permeability......Page 730
Steamboat Springs, Nevada, Hydrothermal System......Page 731
References......Page 735
General Research Considerations......Page 737
Research Recommendations for Geology......Page 738
Research Recommendations for Internal Friction Measurements......Page 739
Research Recommendations for the Evaluation of Physical and Mechanical Properties......Page 740
Recommendations......Page 742
Resolving Power......Page 744
Data Reduction and Interpretation......Page 745
Summary......Page 746
Hydrothermal Systems......Page 748
Index\0\0\0\0\0\0\0\0\0\0\0\0......Page 750
List of Participants......Page 754