ebook ebooks e-book e-books downloaden bei MyEbooks.ch downloaden

Instrumentation in Earthquake Seismology

:	J. Havskov, G. Alguacil
:	Instrumentation in Earthquake Seismology
:	Springer Netherlands
:	9781402029691
:	1
:	CHF 82.60
:

:	Naturwissenschaft
:	English

:	365
:	DRM
:	PC/MAC/eReader/Tablet
:	PDF

This work offers a unique coverage of modern seismic instrumentation. It provides not only detailed information on the basic understanding of seismic instruments but it also includes an overview of current equipment on the market.Furthermore, the following topics are included: - installing seismic stations, networks, and arrays - working with portable instruments - calibrating instruments - dealing with response information - and teaching about seismic instruments.This book is primarily intended for seismologists and technicians working with seismological instruments. The aim is that it should be used as a practical tool with only the amount of theory needed to understand the basic principles, and the answers to most practical problems should be found here.This book is written in such a way that it is understandable for a broad range of professionals working with seismological instruments and seismic data, whether students, engineers, or seismologists. Both practical and theoretical topics are covered, with the main emphasis on practical aspects. The book is based on the authors` (seismologist and physicist) experience working in this field for more than 25 years. TOC:Preface.- Introduction.- Seismic sensors.- Seismic noise.- Analog to digital converter.- Seismic Recorders.- Correction for instrument response.- Seismic stations.- Seismic networks.- Seismic arrays.- Calibration and testing.- Appendix: Basic electronics.- References.- Company references.- Index.

	Table of contents	6
	Preface	11
	Chapter 1	13
	Introduction	13
	1.1 Sensor	14
	1.2 Recorder	18
	1.3 Stations and networks	19
	1.4 Arrays	21
	1.5 Instrument correction and calibration	21
	Chapter 2	23
	Seismic Sensors	23
	2.1 The standard inertia seismometer	24
	2.2 Seimometer frequency response	26
	2.3 Seismometer frequency response, alternative solution	29
	2.4 The velocity transducer	32
	2.4.1 Electromagnetic Damping	34
	2.4.2 Polarity Convention	35
	2.5 Instrument response curves, different representation	35
	2.6 Sensor response to transient signals	38
	2.7 Damping constant	39
	2.8 Construction of seismic sensors	42
	2.8.1 The wood Anderson Short Period Torsion Sensor	43
	2.8.2 Long Period Sensors	43
	2.8.3 Garden-Gate	44
	2.8.4 Inverted Pendulum	46
	2.8.5 Lacoste	46
	2.9 Sensor calibration coil	48
	2.10 Active sensors	50
	2.11 Accelerometers	51
	2.12 Velocity broadband sensors	52
	2.13 Extending the frequency response, inverse filtering and feed back	54
	2.14 Theoretical aspects of active sensor	55
	2.14.1 General Response of a Feedback system	55
	2.14.2 The Basic Force-Balanced Accelerometer	56
	2.14.3 Broadband Feedback Seismometers	59
	2.14.4 Other Feedback Techniques	61
	2.15 Sensor self noise	63
	2.16 Noise in passive sensors coupled to amplifiers, theoretical aspects	67
	2.17 Some new trends in seismic sensors	72
	2.17.1 Seismometers with Electrochemical Transducers	72
	2.18 Sensor parameters	75
	2.18.1 Frequency Response	76
	2.18.2 Sensitivity	76
	2.18.3 Sensor Dynamic Range	77
	2.18.4 Sensor Linearity	78
	2.18.5 Sensor Cross axis Sensitivity	78
	2.18.6 Sensor Gain and Output	79
	2.19 Examples of sensors	79
	2.19.1 Exploration Type 4.5 HZ Geophone	80
	2.19.2 Short Period Sensor, The L4-C	80
	2.19.3 Accelerometer, The Kinemetrics Episensor	80
	2.19.4 Broadband Sensors, The Streckeisen STS-1 and STS-2 and Guralp CMG-3T	81
	2.19.5 Negative Feedback Sensors, Lennartz LE-3D	83
	2.19.6 Borehole Sensors	83
	2.20 Summary of sensor specifications	84
	2.21 Which sensor to choose	86
	Chapter 3	89
	Seismic noise	89
	3.1 Observation of noise	89
	3.2 Noise spectra	92
	3.3 Relating power spectra to amplitude measurements	92
	3.4 Origin of seismic noise	97
	Chapter 4	98
	Analog to digital converter	98
	4.1 Example of a simple analog to digital converter, the Flash ADC	99
	4.2 Basic ADC properties	100
	4.3 A typical ADC, the Ramp ADC	103
	4.4 Multi channel ADC	104
	4.5 Digitizers for a higher dynamic range	105
	4.6 Oversampling for improvement of the dynamic range	106
	4.7 Sigma Delta ADC, SDADC	109
	4.7.1 How Sigma-Delta Improves Digitization Noise: Theory	113
	4.8 Aliasing	114
	4.9 Anti alias filters	115
	4.10 Examples of digitizers	119
	Chapter 5	123
	Seismic Recorders	123
	5.1 Analog amplifier	123
	5.1.1 Differential Input-Output	124
	5.2 Analog filters	125
	5.2.1 Amplifier Specifications and Noise	127
	5.3 Analog recording	129
	5.4 Introduction to digital recorders	132
	5.5 Digitizing	133
	5.6 Time stamping of data	134
	5.7 Storage media and recording in a ring buffer	137
	5.8 Seismic triggers	138
	5.9 Summary of trigger parameters and their settings	142
	5.10 Communication and data retrieval	145
	5.11 Public domain data acquisition systems	147
	5.12 Seismic recorders in use	148
	5.13 The next generation recorder	150
	5.14 Examples of recorders	151
	5.15 Which recorder to choose	157
	Chapter 6	160
	Correction for instrument response	160
	6.1 Linear systems	162
	6.2 Spectral analysis and the Fourier transform	165
	6.3 Noise power spectrum	172
	6.4 General instrument correction in frequency and time domain	174
	6.5 General representation of the frequency response function	176
	6.6 Anti alias filters	180
	6.7 Instrument correction and polarity	181
	6.8 Combining response curves	182
	6.9 Common ways of giving response information	185
	6.9.1 GSE	186
	6.9.2 SEED	187
	6.9.3 SEISAN	189
	Chapter 7	191
	Seismic stations	191
	7.1 Geographical location of a seismic station	192
	7.2 Site selection and seismic noise survey	193
	7.3 Installation of the seismic station	195
	7.4 Sensor installation	196
	7.4.1 Broadband Sensor Installation	198
	7.4.2 Borehole Installations	202
	7.4.3 What is a Good Vlp Station	203
	7.5 Temporary installation of seismic stations	204
	7.6 Lightning and over-voltage protection	205
	7.7 Power	206
	7.7.1 Stations Running off the Main Ac Supply	207
	7.7.2 Batteries	208
	7.8 Power sources	212
	7.8.1 Solar Cells	212
	7.8.2 Wind Generators	216
	7.