Titre : |
Local and Duration Magnitude Scales for Northern Algeria based on Local Earthquake Data (2010-2022) |
Type de document : |
document électronique |
Auteurs : |
Khaled Roubeche, Auteur ; Fethi Semmane, Directeur de thèse |
Editeur : |
Sétif:UFA1 |
Année de publication : |
2025 |
Importance : |
1 vol (162 f.) |
Format : |
29 cm |
Langues : |
Anglais (eng) |
Catégories : |
Thèses & Mémoires:Physique
|
Mots-clés : |
Earthquake
Seismic waves
Attenuation
Local magnitude
Duration magnitude
Northern Algeria |
Index. décimale : |
530 - Physique |
Résumé : |
The study of earthquake magnitudes plays a crucial role in understanding seismic events, their
impacts, and the tectonic processes that shape our planet. Earthquake magnitudes, as numerical
measures of an event’s size, provide valuable information about the energy released during an
earthquake, helping to assess the event’s potential for damage and guiding seismic hazard assessments.
Over time, several magnitude scales have been developed to address different types of seismic
waves and varying distances from the earthquake source. These include the Local Magnitude
(ML), SurfaceWave Magnitude (Ms), BodyWave Magnitude (mb), and Moment Magnitude (Mw),
each with its advantages, limitations, and suitable applications. In northern Algeria, a region prone
to seismic activity due to its complex geodynamics and seismotectonic setting, accurate magnitude
determination is essential. The Local Magnitude (ML) and Duration Magnitude (Md) scales are of
particular importance for characterizing earthquakes within the region. The ML scale, developed
by Charles Richter in the 1930s, remains one of the most widely used scales, particularly for small
to moderate local earthquakes. Meanwhile, the Md scale, which measures the duration of seismic
waves, provides an important supplement toML, especially for larger and deeper earthquakes. Understanding
these scales and their applications in northern Algeria is vital for earthquake hazard
mitigation, infrastructure planning, and public safety. This thesis aims to explore and refine the
calculation and use of magnitude scales, specifically focusing on the Local Magnitude (ML) and
Duration Magnitude (Md) scales, in the context of northern Algeria. By developing a comprehensive
understanding of these scales, this study contributes to the ongoing efforts to enhance seismic
monitoring and improve earthquake magnitude estimation techniques in the region |
Note de contenu : |
Sommaire
Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Résumé . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
General Introduction 18
1 Geological setting in northern Algeria 24
1.1 General geology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
1.1.1 Geodynamics and Seismotectonics . . . . . . . . . . . . . . . . . . . . . . 26
1.1.2 Geomorphological setting . . . . . . . . . . . . . . . . . . . . . . . . . . 30
1.2 Main factors influencing magnitude estimation . . . . . . . . . . . . . . . . . . . 32
1.2.1 Geological factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
1.2.2 Seismic factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
1.3 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
2 Earthquake magnitude and intensity scales 42
2.1 Intensity scales . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
2.1.1 Steps in Macroseismic Studies . . . . . . . . . . . . . . . . . . . . . . . . 47
2.1.2 Isoseismal Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
2.2 Magnitude scales . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
2.2.1 Local magnitude (ML) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
2.2.2 Duration Magnitude (Md) . . . . . . . . . . . . . . . . . . . . . . . . . . 53
2.2.3 Surface Wave Magnitude (Ms) . . . . . . . . . . . . . . . . . . . . . . . . 54
2.2.4 Body Wave Magnitude (mb) . . . . . . . . . . . . . . . . . . . . . . . . . 54
2.2.5 Moment Magnitude (Mw) . . . . . . . . . . . . . . . . . . . . . . . . . . 55
2.3 Why are different magnitude values announced by different agencies when an
earthquake occurs? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
2.4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
3 Data and Methods 68
3.1 Data and networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
3.1.1 Algerian seismological networks . . . . . . . . . . . . . . . . . . . . . . . 69
3.1.2 Characterization of Seismological Data and Used Instrumentation . . . . . 72
3.1.3 Phases Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
3.1.4 Development of a Continuous Seismic Database . . . . . . . . . . . . . . 78
3.1.5 Instrument Response Deconvolution . . . . . . . . . . . . . . . . . . . . . 80
3.2 Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
3.2.1 Local Magnitude (ML) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
3.2.2 Duration magnitude (Md) . . . . . . . . . . . . . . . . . . . . . . . . . . 92
3.3 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
4 A Local Magnitude Scale (ML) for Northern Algeria 96
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
4.2 Seismic Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
4.3 Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
4.4 Results and Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
4.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
5 A Duration Magnitude scale (Md) for northern Algeria 113
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
5.1.1 Data and Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
5.2 Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
5.2.1 Regression Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
5.2.2 Station Corrections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
5.3 Results and Discussions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
5.4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
General Conclusion 135
Bibloigraphy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
A Scientific contributions 152 |
Côte titre : |
Dph/0314 |
Local and Duration Magnitude Scales for Northern Algeria based on Local Earthquake Data (2010-2022) [document électronique] / Khaled Roubeche, Auteur ; Fethi Semmane, Directeur de thèse . - [S.l.] : Sétif:UFA1, 2025 . - 1 vol (162 f.) ; 29 cm. Langues : Anglais ( eng)
Catégories : |
Thèses & Mémoires:Physique
|
Mots-clés : |
Earthquake
Seismic waves
Attenuation
Local magnitude
Duration magnitude
Northern Algeria |
Index. décimale : |
530 - Physique |
Résumé : |
The study of earthquake magnitudes plays a crucial role in understanding seismic events, their
impacts, and the tectonic processes that shape our planet. Earthquake magnitudes, as numerical
measures of an event’s size, provide valuable information about the energy released during an
earthquake, helping to assess the event’s potential for damage and guiding seismic hazard assessments.
Over time, several magnitude scales have been developed to address different types of seismic
waves and varying distances from the earthquake source. These include the Local Magnitude
(ML), SurfaceWave Magnitude (Ms), BodyWave Magnitude (mb), and Moment Magnitude (Mw),
each with its advantages, limitations, and suitable applications. In northern Algeria, a region prone
to seismic activity due to its complex geodynamics and seismotectonic setting, accurate magnitude
determination is essential. The Local Magnitude (ML) and Duration Magnitude (Md) scales are of
particular importance for characterizing earthquakes within the region. The ML scale, developed
by Charles Richter in the 1930s, remains one of the most widely used scales, particularly for small
to moderate local earthquakes. Meanwhile, the Md scale, which measures the duration of seismic
waves, provides an important supplement toML, especially for larger and deeper earthquakes. Understanding
these scales and their applications in northern Algeria is vital for earthquake hazard
mitigation, infrastructure planning, and public safety. This thesis aims to explore and refine the
calculation and use of magnitude scales, specifically focusing on the Local Magnitude (ML) and
Duration Magnitude (Md) scales, in the context of northern Algeria. By developing a comprehensive
understanding of these scales, this study contributes to the ongoing efforts to enhance seismic
monitoring and improve earthquake magnitude estimation techniques in the region |
Note de contenu : |
Sommaire
Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Résumé . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
General Introduction 18
1 Geological setting in northern Algeria 24
1.1 General geology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
1.1.1 Geodynamics and Seismotectonics . . . . . . . . . . . . . . . . . . . . . . 26
1.1.2 Geomorphological setting . . . . . . . . . . . . . . . . . . . . . . . . . . 30
1.2 Main factors influencing magnitude estimation . . . . . . . . . . . . . . . . . . . 32
1.2.1 Geological factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
1.2.2 Seismic factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
1.3 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
2 Earthquake magnitude and intensity scales 42
2.1 Intensity scales . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
2.1.1 Steps in Macroseismic Studies . . . . . . . . . . . . . . . . . . . . . . . . 47
2.1.2 Isoseismal Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
2.2 Magnitude scales . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
2.2.1 Local magnitude (ML) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
2.2.2 Duration Magnitude (Md) . . . . . . . . . . . . . . . . . . . . . . . . . . 53
2.2.3 Surface Wave Magnitude (Ms) . . . . . . . . . . . . . . . . . . . . . . . . 54
2.2.4 Body Wave Magnitude (mb) . . . . . . . . . . . . . . . . . . . . . . . . . 54
2.2.5 Moment Magnitude (Mw) . . . . . . . . . . . . . . . . . . . . . . . . . . 55
2.3 Why are different magnitude values announced by different agencies when an
earthquake occurs? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
2.4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
3 Data and Methods 68
3.1 Data and networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
3.1.1 Algerian seismological networks . . . . . . . . . . . . . . . . . . . . . . . 69
3.1.2 Characterization of Seismological Data and Used Instrumentation . . . . . 72
3.1.3 Phases Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
3.1.4 Development of a Continuous Seismic Database . . . . . . . . . . . . . . 78
3.1.5 Instrument Response Deconvolution . . . . . . . . . . . . . . . . . . . . . 80
3.2 Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
3.2.1 Local Magnitude (ML) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
3.2.2 Duration magnitude (Md) . . . . . . . . . . . . . . . . . . . . . . . . . . 92
3.3 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
4 A Local Magnitude Scale (ML) for Northern Algeria 96
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
4.2 Seismic Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
4.3 Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
4.4 Results and Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
4.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
5 A Duration Magnitude scale (Md) for northern Algeria 113
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
5.1.1 Data and Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
5.2 Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
5.2.1 Regression Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
5.2.2 Station Corrections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
5.3 Results and Discussions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
5.4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
General Conclusion 135
Bibloigraphy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
A Scientific contributions 152 |
Côte titre : |
Dph/0314 |
|