scholarly journals Local Earthquake Magnitude Scale andb‐Value for the Danakil Region of Northern Afar

2017 ◽  
Vol 107 (2) ◽  
pp. 521-531 ◽  
Author(s):  
Finnigan Illsley‐Kemp ◽  
Derek Keir ◽  
Jonathan M. Bull ◽  
Atalay Ayele ◽  
James O. S. Hammond ◽  
...  

2006 ◽  
Vol 96 (6) ◽  
pp. 2221-2230 ◽  
Author(s):  
D. Keir ◽  
G. W. Stuart ◽  
A. Jackson ◽  
A. Ayele


2014 ◽  
Vol 8 (4) ◽  
pp. 1921-1930 ◽  
Author(s):  
H. E. Abdel Hafiez ◽  
I. El-Hussain ◽  
A. E. Khalil ◽  
A. Deif


1993 ◽  
Vol 217 (3-4) ◽  
pp. 243-253 ◽  
Author(s):  
P. Hatzidimitriou ◽  
C. Papazachos ◽  
A. Kiratzi ◽  
N. Theodulidis


Author(s):  
Vivien He

Abstract Earthquakes are a major global risk. The current earthquake early warning systems based on public seismic stations face challenges such as high cost, low density, high latency, no alert zone, and difficulty in predicting ground motions at the location of the user. This article pursues an alternative consumer-based approach. An Internet of Things consumer device, called a “Qube,” was built for a cost below $100 and is about the size of a Rubik’s cube. The Qube successfully detected earthquakes and issued earthquake warnings through sounding the onboard alarm for on-site warning and sending text messages to local subscribers for regional warning. The Qube is highly sensitive. During nine months of testing from September 2020 to May 2021, it detected all earthquakes over M 3.0 magnitude around Los Angeles, as well as nearby earthquakes down to M 2.3. The Qube uses a geophone for ground-motion velocity sensing and captures earthquake waveforms consistent with a nearby broadband seismometer in the Southern California Seismic Network. By analyzing data of the earthquakes detected by the Qube, an empirical logarithmic formula that is used to estimate local earthquake magnitude based on detected ground-motion amplitude in digital counts was developed. Although the Qube’s response in digital counts to ground-motion velocity in μm/s has not been determined, the empirical formula between Qube’s output and local earthquake magnitude suggests the Qube’s consistency in ground-motion measurement. The Qube has Wi-Fi connectivity and is controllable via a smartphone or computer. The combination of low cost, high sensitivity, and integrated alarm function of the Qube is intended to enable a consumer-based approach with the potential for mass adoption and use in dense networks, creating new opportunities for seismic network, earthquake warning, and educational applications.



2011 ◽  
Vol 59 (2) ◽  
pp. 861-869 ◽  
Author(s):  
T. Kuo ◽  
C. Lin ◽  
C. Su ◽  
C. Liu ◽  
C. H. Lin ◽  
...  


1975 ◽  
Vol 65 (2) ◽  
pp. 307-321
Author(s):  
M. D. Trifunac ◽  
A. G. Brady

abstract A quantitative measure of the Modified Mercalli Intensity Scale for earthquakes in the western United States has been developed by correlating the peak seismoscope relative displacement response, Sd, with the reported site intensity, IMM. This correlation can be approximated by S ̄ d ( cm ) ≈ 1 49.2 10 0.288 I MM for IMM ≦ VIII and is characterized by one standard deviation of about 0.7 S̄d. The data used in this study do not indicate an obvious type of dependence of Sd on local site conditions. A method for computing the analog of the local earthquake magnitude, Mseismoscope, has been presented for possible use in strong-motion seismology and for scaling earthquakes by close-in measuremients, when other seismological instruments may go off scale.



1962 ◽  
Vol 6 (1) ◽  
pp. 41-48 ◽  
Author(s):  
V. Kárník ◽  
N. V. Kondorskaya ◽  
Ju. V. Riznitchenko ◽  
E. F. Savarensky ◽  
S. L. Soloviev ◽  
...  


1935 ◽  
Vol 25 (1) ◽  
pp. 1-32 ◽  
Author(s):  
Charles F. Richter

Abstract Summary



1956 ◽  
Vol 46 (2) ◽  
pp. 105-145 ◽  
Author(s):  
B. Gutenberg ◽  
C. F. Richter

Abstract This supersedes Paper 1 (Gutenberg and Richter, 1942). Additional data are presented. Revisions involving intensity and acceleration are minor. The equation log a = I/3 − 1/2 is retained. The magnitude-energy relation is revised as follows: (20) log ⁡ E = 9.4 + 2.14 M − 0.054 M 2 A numerical equivalent, for M from 1 to 8.6, is (21) log ⁡ E = 9.1 + 1.75 M + log ⁡ ( 9 − M ) Equation (20) is based on (7) log ⁡ ( A 0 / T 0 ) = − 0.76 + 0.91 M − 0.027 M 2 applying at an assumed point epicenter. Eq. (7) is derived empirically from readings of torsion seismometers and USCGS accelerographs. Amplitudes at the USCGS locations have been divided by an average factor of 2 1/2 to compensate for difference in ground; previously this correction was neglected, and log E was overestimated by 0.8. The terms M2 are due partly to the response of the torsion seismometers as affected by increase of ground period with M, partly to the use of surface waves to determine M. If MS results from surface waves, MB from body waves, approximately (27) M S − M B = 0.4 ( M S − 7 ) It appears that MB corresponds more closely to the magnitude scale determined for local earthquakes. A complete revision of the magnitude scale, with appropriate tables and charts, is in preparation. This will probably be based on A/T rather than amplitudes.



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