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1.
Result of the algorithm of earthquake prediction, published in 1982, is examined in this paper. The algorithm is based on the hypothesis of long-range interaction between strong and moderate earthquakes in a region. It has been applied to the prediction of earthquakes withM6.4 in Southern California for the time interval 1932–1979. The retrospective results were as follows: 9 out of 10 strong earthquakes were predicted with average spatial accuracy of 58 km and average delay time (the time interval between a strong earthquake and its best precursor) 9.4 years varying from 0.8 to 27.9 years. During the time interval following the period studied in that publication, namely in 1980–1988, four earthquakes occurred in the region which had a magnitude ofM6.4 at least in one of the catalogs: Caltech or NOAA. Three earthquakes—Coalinga of May, 1983, Chalfant Valley of July, 1985 and Superstition Hills of November, 1987—were successfully predicted by the published algorithm.The missed event is a couple of two Mammoth Lake earthquakes of May, 1980 which we consider as one event due to their time-space closeness. This event occurred near the northern boundary of the region, and it also would have been predicted if we had moved the northern boundary from 38°N to the 39°N; the precision of the prediction in this case would be 30 km.The average area declared by the algorithm as the area of increased probability of strong earthquake, e.g., the area within 111-km distance of all long-range aftershocks currently present on the map of the region during 1980–1988 is equal to 47% of the total area of the region if the latter is measured in accordance with the density distribution of earthquakes in California, approximated by the catalog of earthquakes withM5. In geometrical terms it is approximately equal to 17% of the total area.Thus the result of the real time test shows a 1.6 times increase of the occurrence ofC-events in the alarmed area relative to the normal rate of seismicity. Due to the small size of the sample, it is of course, beyond the statistically significant value. We adjust the parameters of the algorithm in accordance with the new material and publish them here for further real-time testing.  相似文献   

2.
The North Anatolian fault is a well-defined tectonic feature extending for 1400 km across Northern Turkey. The space-time distribution of seismicity and faulting of this zone has been examined with a particular emphasis on the identification of possible seismic gaps. Results suggest several conclusions with respect to the temporal and spatial distribution of seismicity. First, the earthquake activity appears not to be stationary over time. Periods of high activity in 1850–1900 and 1940 to the present bracket a period of relatively low activity in 1910–39. Second, there appears to have been a two-directional migration of earthquake epicenters away from a central region located at about 39°E longitude. The migration to the west has a higher velocity (>50 km/yr) than the migration to the east (10km/yr). The faulting associated with successive earthquakes generally abuts the previous rupture. Some existing gaps were filled by later earthquakes.At present there are two possible seismic gaps along the North Anatolian fault zone. One is at the western end of the fault, from about 29° to 30°E. Unless this is a region of ongoing aseismic creep, it could be the site of a magnitude 6 or greater earthquake. The other possible gap is at the eastern end, from about 42° to 43°E, to the west of the unexpected M=7.3 event of 24 November 1976.  相似文献   

3.
Summary The average dependence of the calibration function q and the travel-time residuals t on the depth and distance of the source has been derived for individual branches of PKP waves using earthquakes from the SW Pacific Ocean (distance interval 147°–159°, depths 0–700 km). The analysis of very distant shocks of all depths according to the regional PKP travel time tables can be completed by the magnitude determination.  相似文献   

4.
The Cocos plate subducts beneath North America at the Mexico trench. The northernmost segment of this trench, between the Orozco and Rivera fracture zones, has ruptured in a sequence of five large earthquakes from 1973 to 1985; the Jan. 30, 1973 Colima event (M s 7.5) at the northern end of the segment near Rivera fracture zone; the Mar. 14, 1979 Petatlan event (M s 7.6) at the southern end of the segment on the Orozco fracture zone; the Oct. 25, 1981 Playa Azul event (M s 7.3) in the middle of the Michoacan gap; the Sept. 19, 1985 Michoacan mainshock (M s 8.1); and the Sept. 21, 1985 Michoacan aftershock (M s 7.6) that reruptured part of the Petatlan zone. Body wave inversion for the rupture process of these earthquakes finds the best: earthquake depth; focal mechanism; overall source time function; and seismic moment, for each earthquake. In addition, we have determined spatial concentrations of seismic moment release for the Colima earthquake, and the Michoacan mainshock and aftershock. These spatial concentrations of slip are interpreted as asperities; and the resultant asperity distribution for Mexico is compared to other subduction zones. The body wave inversion technique also determines theMoment Tensor Rate Functions; but there is no evidence for statistically significant changes in the moment tensor during rupture for any of the five earthquakes. An appendix describes theMoment Tensor Rate Functions methodology in detail.The systematic bias between global and regional determinations of epicentral locations in Mexico must be resolved to enable plotting of asperities with aftershocks and geographic features. We have spatially shifted all of our results to regional determinations of epicenters. The best point source depths for the five earthquakes are all above 30 km, consistent with the idea that the down-dip edge of the seismogenic plate interface in Mexico is shallow compared to other subduction zones. Consideration of uncertainties in the focal mechanisms allows us to state that all five earthquakes occurred on fault planes with the same strike (N65°W to N70°W) and dip (15±3°), except for the smaller Playa Azul event at the down-dip edge which has a steeper dip angle of 20 to 25°. However, the Petatlan earthquake does prefer a fault plane that is rotated to a more east-west orientation—one explanation may be that this earthquake is located near the crest of the subducting Orozco fracture zone. The slip vectors of all five earthquakes are similar and generally consistent with the NUVEL-predicted Cocos-North America convergence direction of N33°E for this segment. The most important deviation is the more northerly slip direction for the Petatlan earthquake. Also, the slip vectors from the Harvard CMT solutions for large and small events in this segment prefer an overall convergence direction of about N20°E to N25°E.All five earthquakes share a common feature in the rupture process: each earthquake has a small initial precursory arrival followed by a large pulse of moment release with a distinct onset. The delay time varies from 4 s for the Playa Azul event to 8 s for the Colima event. While there is some evidence of spatial concentration of moment release for each event, our overall asperity distribution for the northern Mexico segment consists of one clear asperity, in the epicentral region of the 1973 Colima earthquake, and then a scattering of diffuse and overlapping regions of high moment release for the remainder of the segment. This character is directly displayed in the overlapping of rupture zones between the 1979 Petatlan event and the 1985 Michoacan aftershock. This character of the asperity distribution is in contrast to the widely spaced distinct asperities in the northern Japan-Kuriles Islands subduction zone, but is somewhat similar to the asperity distributions found in the central Peru and Santa Cruz Islands subduction zones. Subduction of the Orozco fracture zone may strongly affect the seismogenic character as the overlapping rupture zones are located on the crest of the subducted fracture zone. There is also a distinct change in the physiography of the upper plate that coincides with the subducting fracture zone, and the Guerrero seismic gap to the south of the Petatlan earthquake is in the wake of the Orozco fracture zone. At the northern end, the Rivera fracture zone in the subducting plate and the Colima graben in the upper plate coincide with the northernmost extent of the Colima rupture zone.  相似文献   

5.
This paper describes a travel—time analysis performed for the Italian seismic stations, in particular those operating in southern Italy, in order to study the crust and upper mantle properties in the region. Average P-wave residuals of teleseisms in the distance range 30°–95° with respect to Jeffreys-Bullen tables, at thirteen permanent and temporary stations of southern Italy, are coherent with a high velocity zone beneath Calabria and northern Sicily and low velocity material in the mantle beneath the Eolian Islands. Travel—time residuals from Tyrrhenian intermediate earthquakes show a high velocity structure which extends in a NW direction from a depth of at least 200 km down to 450 km.A damped least-squares inversion applied to DSS data confirms the existence of low velocity zones in the crust beneath the Eolian Islands, at 8–12 km depth, that agrees with previous results and with the lack of S waves from local earthquakes.Publication No. 193, Progetto Finalizzato Geodinamica, CNR-Roma.  相似文献   

6.
Summary Ozone observations made during 1964 and 1965 at nine Mediterranean, central and southeast European stations (latitudes 38–52°N, longitudes 9–23°E) reveal patterns of seasonal and shorter time-variations in total ozone as well as in vertical ozone distribution. During the winter-spring season, a significant increase (20%) of ozone occurs essentially simultaneously with the spring stratospheric warming, and is noticed at all stations.—Autocorrelation coefficients show that the total ozone on any day is strongly related to the total ozone of the preceding four days in summer or one or two days in winter-spring or autumn. Changes of total ozone in southeast Europe correlate closely with those in Mediterranean Europe, and less closely with those from north central Europe.—Power spectrum analysis detects the dependence of ozone changes on processes with periods longer than 6–8 days, and indicates a significant oscillation with a period of 14–15 days, perhaps a result of the direct influence of lower stratospheric circumhemispheric circulation. — Reliable vertical ozone soundings were not available from all stations. The mean vertical profiles at Arosa, Switzerland (47°N) and Belsk, Poland (51°) are very similar. More than 60% of the variability of the total ozone is contributed by changes in ozone concentration between 10 and 24 km; less than 10% is due to variations above 33 km. Changes in ozone partial pressure at different altitudes, and relationships of those changes to total ozone, indicates that a mean vertical ozone distribution may be described adequately by considering the ozone changes in four layers: a) the troposphere, b) the lower stratosphere up to 24 km, c) a transition layer from 24 km to a variable upper border at 33–37 km, and d) the layer above 33–37 km.Part of this paper was presented at the Ozone Seminar in Potsdam, Germany, 27 September 1966.  相似文献   

7.
The distribution of the focal mechanisms of the shallow and intermediate depth (h>40 km) earthquakes of the Aegean and the surrounding area is discussed. The data consist of all events of the period 1963–1986 for the shallow, and 1961–1985 for the intermediate depth earthquakes, withM s 5.5. For this purpose, all published fault plane solutions for each event have been collected, reproduced, carefully checked and if possible improved accordingly. The distribution of the focal mechanisms of the earthquakes in the Aegean declares the existence of thrust faulting following the coastline of southern Yugoslavia, Albania and western Greece extending up to the island of Cephalonia. This zone of compression is due to the collision between two continental lithospheres (Apulian-Eurasian). The subduction of the African lithosphere under the Aegean results in the occurrence of thrust faulting along the convex side of the Hellenic arc. These two zones of compression are connected via strike-slip faulting observed at the area of Cephalonia island. TheP axis along the convex side of the arc keeps approximately the same strike throughout the arc (210° NNE-SSW) and plunges with a mean angle of 24° to southwest. The broad mainland of Greece as well as western Turkey are dominated by normal faulting with theT axis striking almost NS (with a trend of 174° for Greece and 180° for western Turkey). The intermediate depth seismicity is distributed into two segments of the Benioff zone. In the shallower part of the Benioff zone, which is found directly beneath the inner slope of the sedimentary arc of the Hellenic arc, earthquakes with depths in the range 40–100 km are distributed. The dip angle of the Benioff zone in this area is found equal to 23°. This part of the Benioff zone is coupled with the seismic zone of shallow earthquakes along the arc and it is here that the greatest earthquakes have been observed (M s 8.0). The deeper part (inner) of the Benioff zone, where the earthquakes with depths in the range 100–180 km are distributed, dips with a mean angle of 38° below the volcanic arc of southern Aegean.  相似文献   

8.
An earthquake sequence comprising almost 2000 events occurred in February–July 2001 on the southern coast of the Corinth Gulf.Several location methods were applied to 171 events recorded by the regional network PATNET. The unavailability of S-wave readings precluded from reliable depth determination. For the mainshock of April 8, ML= 4.7, the depth varied from 0 to 20 km. The amplitude spectra of complete waveforms at three local stations (KER,SER, DES; epicentral distances 17, 26 and 56 km) were inverted between 0.1 and 0.2 Hz for double-couple focal mechanism and also for the depth. The optimum solution (strike 220°, dip 40°, rake ‒160°, and depth of 8 km) was validated by forward waveform modeling.Additionally, the mainshock depth was further supported by the P- and S-wave arrival times from the local short-period network CRLNET (Corinth Rift Laboratory).The scalar seismic moment was 2.5e15 Nm,and the moment rate function was successfully simulated by a triangle of the 0.5 second duration. This is equivalent to a 1–1.5 km fault length, and a static stress drop 2–6 MPa. This value is important for future strong ground motion simulation of damaging earthquakes in Aegion region, whose subevents may be modeled according to the studied event. The T axis of the mainshock (azimuth 176° and plunge 67°), is consistent with the regional direction of extension N10°. However, none of the nodal planes can be associated to an active structure seen at the surface. The relationship of this earthquake sequence with deeper faults (e.g. possible detachment at about 10 km) is also unclear.  相似文献   

9.
To better understand the mechanics of subduction and the process of breaking a mature seismic gap, we study seismic activity along the western New Britain subduction segment (147°E–151°E, 4°S–8°S) through earthquakes withm b 5.0 in the outer-rise, the upper area of subducting slab and at intermediate depths to 250 km, from January 1964 to December 1990. The segment last broke fully in large earthquakes of December, 28, 1945 (M s =7.9) and May 6, 1947 (M s =7.7.), and its higher seismic potential has been recognized byMcCann et al., (1979). Recently the segment broke partially in two smaller events of February, 8, 1987 (M s =7.4) and October 16, 1987 (M s =7.4), leaving still unbroken areas.We observe from focal mechanisms that the outer-rise along the whole segment was under pronounced compression from the late 60's to at least October 1987 (with exception of the tensional earthquake of December 11, 1985), signifying the mature stage of the earthquake cycle. Simultaneously the slab at intermediate depths below 40 km was under tension before the earthquake of October 16, 1987. That event, with a smooth rupture lasting 32 sec, rupture velocity of 2.0 km/sec, extent of approximately 70 km and moment of 1.2×1027 dyne-cm, did not change significantly the compressive state of stress in the outer-rise of that segment. The earthquake did not fill the gap completely and this segment is still capable of rupturing either in an earthquake which would fill the gap between the 1987 and 1971 events, or in a larger magnitude event (M s =7.7–7.9), comparable to earthquakes observed in that segment in 1906, 1945 and 1947.  相似文献   

10.
Summary Distribution of compressional-wave velocities in the mantle is determined fromdT/d measurements using the Uppsala seismograph array station (UPSAS). Short-period vertical-component seismograms from 181 events in the epicentral distance range 16°–100° have been used. The velocity distribution shows anomalous variations at depths of 750, 1500, 1800, 2300 and 2550 km. Evidence of lateral heterogeneity beneath the northern part of the Asian continent, in the depth range 1700–2300 km, is discussed. Computed travel times, based on this velocity-depth relation, are tested by an examination of travel-time residuals from the Long Shot and Milrow explosions on Amchitka, Aleutian Islands.  相似文献   

11.
The Sterea Hellas (central Greece) gravity network was remeasured in 1982, with the addition of 40 new stations. There were no statistically significant gravity differences for most of the gravity stations first established in 1968, but four stations—Arta, Preveza, Levadia, and Kymi—exhibited gravity changes of –121, –74, –39, and –67 gal, respectively.In the absence of repeat levelling, the exact amount of vertical displacement cannot be determined. Nevertheless, for Arta and Preveza some theoretical estimates can be made from shallow seismicity data. The vertical displacement deduced from a seismic-moment calculation for the western part of Greece was found to be about 100 mm, corresponding to a slip rate of approximately 7.5 mm/yr. The corresponding gravity change is too small to account fully for that observed at Arta and Preveza. For the rest, other causes, such as creep, should be considered. For the stations Kymi and Levadia the local seismicity is limited, and no calculation was made of the vertical displacement related to earthquakes.Finally, the possibilities in using the central Greece gravity network for studies of earthquake prediction are discussed.  相似文献   

12.
A methodology is proposed to determine design earthquakes for site-specific studies such as the siting of critical structures (power plants, waste disposals, large dams, etc.), strategic structures (fire stations, military commands, hospitals, etc.), or for seismic microzoning studies, matching the results of probabilistic seismic hazard analyses. This goal is achieved by calculating the source contribution to hazard and the magnitude–distance deaggregation, showing that, varying the selected frequency and the level of hazard, the reference earthquakes are changed as a result. A procedure is then adopted to minimize the residuals between the uniform hazard spectrum (target motion) and the design earthquake spectrum, to provide a specific earthquake scenario encompassing all the frequencies of the target motion. Finally, some considerations on the use and the influence exerted by ground motion uncertainty (σ) on hazard deaggregation are outlined.  相似文献   

13.
Ozonesonde data are matched with concomitant rawinsonde data to provide a direct determination of horizontal, meridional, flux of ozone by the transient eddies. Data are from 27 stations in 4 regions: Eastern and western North America, western Europe, and Japan. Results confirm the existence of significant northward flux near 40°N, 10–18 km, in winter and spring, as shown by previous investigators. However, areas of significant equatorward flux are found at high mid-latitudes, 10–16 km, over North America in winter and spring, and at all 3 Japanese stations, 10–18 km, in spring. Transient eddy fluxes are typically small in summer, and are also small throughout the troposphere and most of the middle stratosphere.  相似文献   

14.
We investigate the nature of temporal variations in the statistical properties of seismicity associated with the North Anatolian Fault Zone between longitudes 31°–41°E during the instrumental period 1900–1992. Temporal variations in the seismicb value and the fractal (correlation) dimensionD c of earthquake epicenters are examined for earthquakes of magnitudeM S 4.5, using sliding windows of 100 consecutive events.b varies temporally between 0.6 and 1.0, andD c between 0.6 and 1.4, both representing significant fluctuations above the errors in measurement technique. A strong negative correlation (r=–0.85) is observed betweenb andD c , consistent with previous observation of seismicity in Japan and southern California. Major events early in this century (M S 7) are associated with lowb and highD c , respectively consistent with greater stress intensity and greater spatial clustering of epicenters—both implying a greater degree of stress concentration at this time.  相似文献   

15.
A sequence of moderate shallow earthquakes (3.5M L5.3) was located within the Vercors massif (France) in the period 1961–1984. This subalpine massif has been a low seismic area for at least 5 centuries. During the period 1962–1963, 12 shallow earthquakes occurred in the neighborhood (10 km) of the Monteynard reservoir, 30 km south of the city of Grenoble. The latest fourM L4.0 earthquakes occurred in 1979–1984 either at larger distance (35 km) or greater depth (10 km) from the reservoir. Two triggering mechanisms are suggested for this sequence: (i) the direct effect of elastic loading through either increased shear stress or strength reducing by increased pore pressure at depth; (ii) the pore pressure diffusion induced by poroelastic stress change due to the reservoir filling.The weekly water levels, local balanced geological cross sections, and focal mechanisms argue for two types of mechanical connection between the earthquake sequence and the filling cycles of the Monteynard reservoir. The seismic sequence started with the 1962–1963 shallow earthquakes that occurred during the first filling of the reservoir and are typical of the direct effect of elastic loading. The 1979 deeper earthquake is located at a 10 km depth below the reservoir. This event occurred 16 years after the initial reservoir impoundment, but one month after the previous 1963 maximum water level was exceeded. Moreover the yearly reservoir level increased gradually in the period 1962–1979 and has decreased since 1980. Accordingly we suggest that the gradual diffusion of water from reservoir to hypocentral depths decreases the strength of the rock matrices through increased pore pressure. The transition between the two types of seismic response is supported by the analysis ofM L3.5 earthquakes which all occurred in the period 1964–1971, ranging between 10 and 30 km distance from the reservoir. The three other delayed earthquakes of the 1961–1984 seismic sequence (M L4 during the 1979–1984 period) are all located 35 km away from the reservoir. Based on the seismic activity, the estimates for the hydraulic diffusivities range between 0.2–10 m2/s, except for the first event that occurred 30 km north of the reservoir, the filling just started. The lack ofin situ measurements of crustal hydrological properties in the area, shared by most of the Reservoir-Induced-Seismicity cases, prevents us from obtaining absolute evidence for the triggering processes. These observations and conceptual models attest that previous recurrence times for moderate natural shocks (4.5M L5.5) estimated within this area using historical data, could be modified by 0.1–1 MPa stress changes. These small changes in deviatoric stress suggest that the upper crust is in this area nearly everywhere at a state of stress near failure. Although the paucity of both number and size of earthquakes in the French subalpine massif shows that aseismic displacements prevail, our study demonstrates that triggered earthquakes are important tools for assessing local seismic risk through mapping fault zones and identifying their possible seismic behavior.  相似文献   

16.
Most large earthquakes of magnitude 6.0 in California during 1852–1987 appear to show a southeast-to-northwest tendency of epicenter migration. This finding is consistent with earlier findings ofSavage (1971) for a relatively few large earthquakes along the west coast of North America, and ofWood andAllen (1973) for smaller events along the San Andreas fault in central California. The average speed of migration is approximately 130 km/yr, which is within the range of speeds observed for other major seismic zones in the world. The epicenter migration in California may be the result of some small but broad-scaled episodic strain changes associated with creep waves induced by magma injections at the East Pacific Rise and propagating northwestwardly along a broad transform boundary between the Pacific and North American plates at subseismogenic depths as proposed bySavage (1971).  相似文献   

17.
The atmospheric spectral transparency variations at 344 nm and 369 nm, averaged at eight Soviet stations between 69°N and 55°N, have been compared with sunspot numbers, or Wolf numbers (WN). The data were taken for the seasonal interval May-August during the period 1972 – 1989. Good negative correlations –0.76 and –0.82 have been found. The correlation coefficient between aerosol extinction at 344 nm and WN is equal to +0.75. Insignificant correlation is found for the transparency variations at 344 nm for stations situated to the south of latitude 50°. The best correlation with WN for both transparency and aerosol extinction at northern stations occurs for the shift of WN ahead of the optical parameters by 6 months. The connection of transparency with cosmic rays in Apatity is also examined. It displays a sign opposite to that for WN, smaller values of the correlation coefficient, and an improbable shift of transparency ahead of cosmic ray intensity. The relative changes of the transparency during a solar cycle can be evaluated at 10% in the ozone-free UVA region  相似文献   

18.
The Timiskaming earthquake, which occurred near the Quebec-Ontario border at the northwest end of the Western Quebec seismic zone in 1935, is one of the five largest instrumentally recorded southeastern Canadian earthquakes. Previous studies of this earthquake concentrated on modeling teismograms recorded at regional distances, a better constrained focal mechanism is obtained. The waveforms indicate thrust faulting on a moderately dipping northwest striking plane at a depth of 10 km. TheM w of 6.1 determined in this study is in good agreement with previous magnitude estimates (m b 6.1,M s 6.0, andm bLg 6.2–6.3). The focal mechanism is similar to those of many recent small to moderate earthquakes in the region, and the inferred (from theP axis) acting stress of northeast compression is consistent with the overall eastern North American stress field. The Lake Timiskaming Rift Valley in which the earthquake occurred, comprises several northwest striking faults consistent with the strike of the 1935 event. Thus, the 1935 earthquake appears to be a result of faulting on the reactivated Timiskaming graben.  相似文献   

19.
During solar cycle 21 (1976–86), the primary solar irradiance at 300 nm was steady during 1980–82 and thereafter decreased until 1986 by only 2–3%. The stratospheric ozone in middle latitudes had a QBO of 3–4% in this interval but the long-term ozone trend was less than 3% per decade, which could result in a UVB increase of only 5–6% per decade. Thus, the combined effect of changes in primary solar irradiance and ozone changes could be an increase of 5–6% in UVB, observed at ground during 1977–81 and a steady level during 1981–86. During 1976–86, the average cloudiness changed by less than 5% indicating UVB changes of 5% or less on this count. The aerosol level was almost constant during 1976–82 and increased abruptly in 1982 due to the E1 Chichon eruption and decayed slowly unitl 1986. Thus, due to aerosols only, the UVB was expected to be constant during 1976–82, to decrease sharply in 1982 and to recoup slowly thereafter.Measurements of clear-sky solar UVB at ground made at Jungfraujoch (Swiss Alps, 47°N, 8°E) during 1981–89 and at Rockville, USA (39°N, 77°W) were not comparable between themselves and did not follow the above expected patterns. Neither did the all-day R-B meter UVB measurements at Philadelphia, USA (40°N, 75°W) and Minneapolis, USA (45°N, 93°W). We suspect that some of these measurements are erroneous. This needs further detailed scrutiny.  相似文献   

20.
The 3 strongest earthquakes,M7.0, which have occurred since 1973 in the area of Greece were preceded by a specific increase of the earthquake activity in the lower magnitude range. This activation is depicted by algorithm M8. This algorithm of intermediate term earthquake prediction was originally designed for diagnosis by Times of Increased Probability (TIPs) of the strongest earthquake,M8.0 worldwide (Keilis-Borok andKossobokov, 1984). At present the algorithm is retrospectively tested for smaller magnitudes in different seismic regions (Keilis-Borok andKossobokov, 1986, 1988). A TIP refers to a time period of 5 years and an area whose linear size is proportional and several times larger than that of the incipient earthquake source. Altogether the TIPs diagnosed by the algorithm M8 in the area of Greece occupy less than 20% and the Times of Expectation (TEs) about 10% of the total space-time domain considered. Also there is a current TIP for the southeastern Aegean sea and 1988–1992. It may specify the long-term prediction given inWyss andBaer (1981a,b).The results of this study are further evidence favoring applicability of algorithm M8 in diverse seismotectonic environment and magnitude ranges and support indirectly the hypothesis of self-similarity of the earthquake activity. It also implies the possibility of intermediate term prediction of the strongest earthquakes in the area of Greece.  相似文献   

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