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1.
Drought is one of the most important natural hazards in Iran. It is especially more prevalent in arid and hyper arid regions where there are serious limitations in regard to providing sufficient water resources. On the other hand, drought modeling and particularly its prediction can play important role in water resources management under conditions of lack of sufficient water resources. Therefore, in this study, drought prediction in a hyper arid location of Iran (Ardakan region) has been surveyed based on the abilities of artificial neural. Standardized Precipitation Index (SPI) in different time scales (3, 6, 9, 12, and 24 monthly time series) computed based on the data gathered from four rain gauge stations. After evaluation and testing of different artificial neural networks (ANN) structures, gradient descent back propagation (traingd) network showed higher abilities than others. Then, the predictions of SPI time series with different monthly lag times (1:12 months) were tested. Generally, drought prediction by ANNs in the Ardakan region has shown considerable results with the correlation coefficient (R) more than 0.79 and in the most cases and it rises more than 0.90, which indicates the ANN’s ability of drought prediction.  相似文献   

2.
An artificial neural networks (ANN) approach combined with Fourier Transform based selection of time period in the time series Radon Emission Data has been presented and shown to improve event prediction rates and reduce false alarms in Earthquake Event Identification over the traditional multiple linear regression techniques. The paper presents a neural networks system using radial basis function (RBF) network as an alternative to traditional statistical regression technique in isolating Radon Emission Anomaly caused by seismic activities. The RBF model has been developed to accept and predict earthquakes events based on a known data set of Radon Emanation, Metrological parameters and actual earthquake events. Subsequently, the model was tested and evaluated on a future data set and a prediction rate of 87.8%, if a reduced false alarm was achieved, the results obtained are better than the traditional techniques.  相似文献   

3.
The goal of this study was to determine whether principal component analysis (PCA) can be used to process GPS ionospheric total electron content (TEC) data on a monthly basis to identify early earthquake-associated TEC anomalies. PCA is applied to GPS (mean value of a month) ionospheric TEC records collected from the Japan GEONET system to detect TEC anomalies associated with 10 earthquakes in Japan (M?≥?6.0) from 2006 to 2007. According to the results, PCA was able to discriminate clear TEC anomalies in the months when all 10 earthquakes occurred. After reviewing the months when no M?≥?6.0 earthquake occurred but the geomagnetic storm activity was present, it is possible that the maximal principal eigenvalues PCA returned for these 10 earthquakes indicate earthquake-associated TEC anomalies. Previously, PCA has been used to discriminate earthquake-associated TEC anomalies recognized by other researchers who found that a statistical association between large earthquakes and TEC anomalies could be established in the 5 days before earthquake nucleation and in 24 h before earthquake; however, since PCA uses the characteristics of principal eigenvalues to determine earthquake-related TEC anomalies, it is possible to show that such anomalies existed earlier than this 5-day statistical window. In this paper, this is shown through the application of PCA to one-dimensional TEC data relating to the earthquake of 17 February 2007 (M?=?6.0). The analysis is applied to daily TEC and reveals a large principal eigenvalue (representative of an earthquake-associated anomaly) for 02 February, 15 days before the 17 February earthquake.  相似文献   

4.
China Metropolitan area around Beijing is one of the earthquake test sites in Continental China. Through more than 20 years of hard work, abundant seismic, geological, geophysical and geochemical data have been obtained, and the variation of seismic, geophysical and geochemical parameters was recorded before several strong earthquakes and some moderate earthquakes in this area. In this paper, we chose 19 high qualified observatory parameters in this area to establish a multidisciplinary system for earthquake forecast, including apparent resistivity, ground water level, ground-level, tilt, radon content in groundwater, volumetric strain, Hg content in groundwater, low frequency electric signal. We calculate the synthetic information by a simple algorithm. The procedure is: firstly, we detect the abnormal intervals of the observatory data by some data analysis methods such as filtering, differencing, etc.; secondly, we endow the value of 1 to the abnormal intervals and 0 to other intervals and produce a new time series of data set of the ith parameter; thirdly, we compose the value of the new time series of 19 observatory parameters and obtain the normalized value as called synthetic information. The result shows that there are high correlations between the high synthetic information and the earthquakes with M ≥ 5.0 in this area. The earthquakes almost occurred several days to several months after the peak value of the synthetic information. This synthetic method might be taken for a short-term prediction method for M ≥ 5.0 earthquakes in this area.  相似文献   

5.
Iran has long been known as one of the most seismically active areas of the world, and it frequently suffers destructive and catastrophic earthquakes that cause heavy loss of human life and widespread damage. The Alborz region in the northern part of Iran is an active EW trending mountain belt of 100 km wide and 600 km long. The Alborz range is bounded by the Talesh Mountains to the west and the Kopet Dagh Mountains to the east and consists of several sedimentary and volcanic layers of Cambrian to Eocene ages that were deformed during the late Cenozoic collision. Several active faults affect the central Alborz. The main active faults are the North Tehran and Mosha faults. The Mosha fault is one of the major active faults in the central Alborz as shown by its strong historical seismicity and its clear morphological signature. Situated in the vicinity of Tehran city, this 150-km-long N100° E trending fault represents an important potential seismic source. For earthquake monitoring and possible future prediction/precursory purposes, a test site has been established in the Alborz mountain region. The proximity to the capital of Iran with its high population density, low frequency but high magnitude earthquake occurrence, and active faults with their historical earthquake events have been considered as the main criteria for this selection. In addition, within the test site, there are hot springs and deep water wells that can be used for physico-chemical and radon gas analysis for earthquake precursory studies. The present activities include magnetic measurements; application of methodology for identification of seismogenic nodes for earthquakes of M ≥ 6.0 in the Alborz region developed by International Institute of Earthquake Prediction Theory and Mathematical Geophysics, IIEPT RAS, Russian Academy of Science, Moscow (IIEPT&MG RAS); a feasibility study using a dense seismic network for identification of future locations of seismic monitoring stations and application of short-term prediction of medium- and large-size earthquakes is based on Markov and extended self-similarity analysis of seismic data. The establishment of the test site is ongoing, and the methodology has been selected based on the IASPEI evaluation report on the most important precursors with installation of (i) a local dense seismic network consisting of 25 short-period seismometers, (ii) a GPS network consisting of eight instruments with 70 stations, (iii) magnetic network with four instruments, and (iv) radon gas and a physico-chemical study on the springs and deep water wells.  相似文献   

6.
The reported study contributes to research on earthquake prediction. Between 2007 and 2009, changes were observed in two geothermal and mineral springs located in Eskipazar (～3–5 km to the north of the North Anatolian Fault Zone) in Turkey, in relation to small-magnitude earthquakes. During pre-seismic and post-seismic activities, variations were observed in the hydrogeological parameters of the spring waters. Temperature increases of 0.4–1°C were measured in one of the springs prior to three different earthquakes. There was a slight increase in the spring discharge with respect to the first earthquake, which occurred closest to the spring. This led to a reduction in electrical conductivity (EC), total dissolved solids (TDS), Ca, HCO3, δ13C, Al, Mn, and Fe concentrations in the spring water, whereas tritium and Se values increased. Several days before the third earthquake, which occurred at a shallower depth, a decrease was observed in the discharge, which led to a reduction in tritium, δ13C and Si concentrations. These variations could be explained by changes in the mixing ratio of waters of different genesis, depending on changes in permeability, pore pressure, and flow paths of the aquifer due to regional stress changes.  相似文献   

7.
We present data analysis of multi-electrode measurements performed in the tectonosphere-atmosphere interface at Pizzoli and Chieti observatories located at distances 30–50 km and 90–110 km from earthquakes epicenters in Central Italy accordingly. Time intervals include 30 days of observations before earthquakes occurred on 24 August (M6.2), on 26 October (M6.1) and on 30 October, 2016 (M6.6). The recorded signals are two component time series with time step 1 s representing alternative and direct electromotive force components. Alternative electromotive force component in frequency band of 0.01 Hz to 4000 Hz is being recorded. Basic study has been carried out since 1989 at Kamchatka peninsula and since 2012 across Eurasia. The observation of nonstationary electric processes illustrates the nucleation of seismogenetic activity. We propose the hypothesis that nonstationary (sudden, abrupt in amplitude) electrical signals illustrate the proton permeability of rocks laying underneath the measuring sensor including a unique phenomenon of anomalous spontaneous deformation due to combination of proton environment and polymorphic transformation in condensed media. One of the interesting results is distinguishing the main zone of major earthquake nucleation which is corresponding as the earthquakes epicenters in Central Italy with M > 6. We suggest that by covering the northern, central and southern parts of Italy with a network of multi-electrode observatories near fault lines, towns and villages could pinpoint the possible coordinates of earthquake epicenter in a 30 day time window. The Chieti and Pizzoli observatories can form the basis of an extended network.  相似文献   

8.
Earthquakes in Kenya are common along the Kenya Rift Valley because of the slow divergent movement of the rift and hydrothermal processes in the geothermal fields. This implies slow but continuous radiation of seismic energy, which relieves stress in the subsurface rocks. On the contrary, the NW-SE trending rift/fault zones such as the Aswa-Nyangia fault zone and the Muglad-Anza-Lamu rift zone are the likely sites of major earthquakes in Kenya and the East African region. These rift/fault zones have been the sites of a number of strong earthquakes in the past such as the M w = 7.2 southern Sudan earthquake of 20 May 1990 and aftershocks of M w = 6.5 and 7.1 on 24 May 1990, the 1937 M s = 6.1 earthquake north of Lake Turkana close to the Kenya-Ethiopian border, and the 1913 M s = 6.0 Turkana earthquake, among others. Source parameters of the 20 May 1990 southern Sudan earthquake show that this earthquake consists of only one event on a fault having strike, dip, and rake of 315°, 84°, and ?3°. The fault plane is characterized by a left-lateral strike slip fault mechanism. The focal depth for this earthquake is 12.1 km, seismic moment M o = 7.65 × 1019 Nm, and moment magnitude, M w = 7.19 (?7.2). The fault rupture started 15 s earlier and lasted for 17 s along a fault plane having dimensions of ?60 km × 40 km. The average fault dislocation is 1.1 m, and the stress drop, ?σ, is 1.63 MPa. The distribution of historical earthquakes (M w ≥ 5) from southern Sudan through central Kenya generally shows a NW-SE alignment of epicenters. On a local scale in Kenya, the NW–SE alignment of epicenters is characterized by earthquakes of local magnitude M l ≤ 4.0, except the 1928 Subukia earthquake (M s = 6.9) in central Kenya. This NW–SE alignment of epicenters is consistent with the trend of the Aswa-Nyangia Fault Zone, from southern Sudan through central Kenya and further southwards into the Indian Ocean. We therefore conclude that the NW–SE trending rift/fault zones are sites of strong earthquakes likely to pose the greatest earthquake hazard in Kenya and the East African region in general.  相似文献   

9.
An instrumental earthquake catalog covering the time span between 1903 and 2007 and for the area bounded by 32°N–38°N and 35°E–43°E has been compiled in this research. The catalog has a magnitude of completeness (M c ) with 3.5. Least squares and statistical probability Gumbel’s techniques with different approaches have been applied on the instrumental events in order to assess the average recurrence time periods for different earthquake magnitudes. The constants a and b of Gutenberg-Richter and the average recurrence times have been computed firstly for the study area and secondly for the central and northern parts of Dead Sea fault system. The different statistical computations using Knopoff and Kagan formalism are generally in agreement and suggest an average recurrence time of 203 years for an earthquake of magnitude 7 for the region. The occurrence of large well-documented historical earthquakes in Lebanon and western Syria, the existence of active fault segments, the absence of large earthquakes during the study period, the increasing number of the low-magnitude earthquakes, and the continued accumulation of the strain since 1900 indicate therefore the probability of an earthquake occurrence of a large magnitude. This should be permanently taken into consideration in seismic hazard assessment on the local and regional scales.  相似文献   

10.

Complexity in the earthquake mechanism is manifested in different forms such as fractal distribution, clustering of seismicity, etc., and characterized as critical phenomenon. Occurrences of earthquakes generally represent the state of metastable equilibrium. The Andaman–Sumatra subduction zone is one of the most seismically active corridors (possibly in metastable state) in the world. Recently, the region faced three major earthquakes of magnitude more than 8.5 (M ~ 9.1 on December 26, 2004; M ~ 8.6 on March 28, 2005; M ~ 8.6 on April 11, 2012). Researchers have suggested multiple causes of earthquake generation in this region including the one with possible correlation of tidal stresses with earthquake occurrences. The latter issue, however, has been hotly debated in view of the fact that a small stress generated due to tidal forcing cannot cause such a bigger magnitude earthquake. We study here the impact of tidal forcing on critically generated earthquake phenomena. We examined the statistical behavior of recurrence time interval of earthquakes using the available data for period of about 40 years from 1973 to 2013. We constrain the simple empirical toy model using the concept of catastrophe theory to evaluate the impact of small tidal forcing on the critical state of earthquakes occurrences. In addition to the major role of Helmholtz free energy during the plate motion, our analysis suggests that the stability and critical behavior of the earthquake in Sumatra region could be associated with tidal forcing, however, only for triggering of some of the “Catastrophic–Chaotic” earthquake phenomenon.

  相似文献   

11.
Complexity in the earthquake mechanism is manifested in different forms such as fractal distribution, clustering of seismicity, etc., and characterized as critical phenomenon. Occurrences of earthquakes generally represent the state of metastable equilibrium. The Andaman–Sumatra subduction zone is one of the most seismically active corridors (possibly in metastable state) in the world. Recently, the region faced three major earthquakes of magnitude more than 8.5 (M ~ 9.1 on December 26, 2004; M ~ 8.6 on March 28, 2005; M ~ 8.6 on April 11, 2012). Researchers have suggested multiple causes of earthquake generation in this region including the one with possible correlation of tidal stresses with earthquake occurrences. The latter issue, however, has been hotly debated in view of the fact that a small stress generated due to tidal forcing cannot cause such a bigger magnitude earthquake. We study here the impact of tidal forcing on critically generated earthquake phenomena. We examined the statistical behavior of recurrence time interval of earthquakes using the available data for period of about 40 years from 1973 to 2013. We constrain the simple empirical toy model using the concept of catastrophe theory to evaluate the impact of small tidal forcing on the critical state of earthquakes occurrences. In addition to the major role of Helmholtz free energy during the plate motion, our analysis suggests that the stability and critical behavior of the earthquake in Sumatra region could be associated with tidal forcing, however, only for triggering of some of the “Catastrophic–Chaotic” earthquake phenomenon.  相似文献   

12.
This paper investigates the prediction of future earthquakes that would occur with magnitude 5.5 or greater using adaptive neuro-fuzzy inference system (ANFIS). For this purpose, the earthquake data between 1950 and 2013 that had been recorded in the region with 2°E longitude and 4°N latitude in Iran has been used. Thereupon, three algorithms including grid partition (GP), subtractive clustering (SC) and fuzzy C-means (FCM) were used to develop models with the structure of ANFIS. Since the earthquake data for the specified region had been reported on different magnitude scales, suitable relationships were determined to convert the magnitude scales into moment magnitude and all records uniformed based on the relationships. The uniform data were used to calculate seismicity indicators, and ANFIS was developed based on considered algorithms. The results showed that ANFIS-FCM with a high accuracy was able to predict earthquake magnitude.  相似文献   

13.
This study examined the spatial-temporal variations in seismicity parameters for the September 10th, 2008 Qeshm earthquake in south Iran. To this aim, artificial neural networks and Adaptive Neural Fuzzy Inference System (ANFIS) were applied. The supervised Radial Basis Function (RBF) network and ANFIS model were implemented because they have shown the efficiency in classification and prediction problems. The eight seismicity parameters were calculated to analyze spatial and temporal seismicity pattern. The data preprocessing that included normalization and Principal Component Analysis (PCA) techniques was led before the data was fed into the RBF network and ANFIS model. Although the accuracy of RBF network and ANFIS model could be evaluated rather similar, the RBF exhibited a higher performance than the ANFIS for prediction of the epicenter area and time of occurrence of the 2008 Qeshm main shock. A proper training on the basis of RBF network and ANFIS model might adopt the physical understanding between seismic data and generate more effective results than conventional prediction approaches. The results of the present study indicated that the RBF neural networks and the ANFIS models could be suitable tools for accurate prediction of epicenteral area as well as time of occurrence of forthcoming strong earthquakes in active seismogenic areas.  相似文献   

14.
The East Anatolian Fault Zone is a continental transform fault accommodating westward motion of the Anatolian fault. This study aims to investigate the source properties of two moderately large and damaging earthquakes which occurred along the transform fault in the last two decades using the teleseismic broadband P and SH body waveforms. The first earthquake, the 27 June 1998 Adana earthquake, occurred beneath the Adana basin, located close to the eastern extreme of Turkey’s Mediterranean coast. The faulting associated with the 1998 Adana earthquake is unilateral to the NE and confined to depths below 15 km with a length of 30 km along the strike (53°) and a dipping of 81° SE. The fixed-rake models fit the data less well than the variable-rake model. The main slip area centered at depth of about 27 km and to the NE of the hypocenter, covering a circular area of 10 km in diameter with a peak slip of about 60 cm. The slip model yields a seismic moment of 3.5?×?1018 N-m (Mw???6.4). The second earthquake, the 1 May 2003 Bingöl earthquake, occurred along a dextral conjugate fault of the East Anatolian Fault Zone. The preferred slip model with a seismic moment of 4.1?×?1018 N-m (Mw???6.4) suggests that the rupture was unilateral toward SE and was controlled by a failure of large asperity roughly circular in shape and centered at a depth of 5 km with peak displacement of about 55 cm. Our results suggest that the 1998 Adana earthquake did not occur on the mapped Göksun Yakap?nar Fault Zone but rather on a SE dipping unmapped fault that may be a split fault of it and buried under the thick (about 6 km) deposits of the Adana basin. For the 2003 Bingöl earthquake, the final slip model requires a rupture plane having 15° different strike than the most possible mapped fault.  相似文献   

15.
The Manyas fault zone (MFZ) is a splay fault of the Yenice Gönen Fault, which is located on the southern branch of the North Anatolian Fault System. The MFZ is a 38 km long, WNW–ESE-trending and normal fault zone comprised of three en-echelon segments. On 6 October 1964, an earthquake (Ms = 6.9) occurred on the Salur segment. In this study, paleoseismic trench studies were performed along the Salur segment. Based on these paleoseismic trench studies, at least three earthquakes resulting in a surface rupture within the last 4000 years, including the 1964 earthquake have been identified and dated. The penultimate event can be correlated with the AD 1323 earthquake. There is no archaeological and/or historical record that can be associated with the oldest earthquake dated between BP 3800 ± 600 and BP 2300 ± 200 years. Additionally, the trench study performed to the north of the Salur segment demonstrates paleoliquefaction structures crossing each other. The surface deformation that occurred during the 1964 earthquake is determined primarily to be the consequence of liquefaction. According to the fault plane slip data, the MFZ is a purely normal fault demonstrating a listric geometry with a dip of 64°–74° to the NNE.  相似文献   

16.
Even though central Virginia is far from the nearest plate boundaries, the region is well-known for minor-to-moderate shocks, which have occurred frequently since at least the eighteenth century. Many of its people have experienced small earthquakes, while infrequent larger ones have caused damage. The largest destructive earthquake (magnitude 5.8) in this seismic zone was recorded in August 2011. Smaller earthquakes that cause little or no damage are felt each year or two. It is difficult to link the earthquakes of this zone to known small faults which are numerous, deeply buried and do not show up at the surface. The mean earthquake depth since 1960 is 6.7 km. On the other hand, central Virginia is a big collector and transporter of precipitation water, which flows to the Atlantic Ocean through the James River and its tributaries. There are about 2,000 abandoned mining sites in Virginia with underground openings that can facilitate the interception and conveyance of surface water. This paper presents evidence that seismic activity in certain zones can be associated clearly with the hydrological effects of abundant precipitation. Such effects can increase tectonic stress, which surpasses the marginal amount when an earthquake occurs. We analyze the cross-correlation between precipitation or water discharge in the rivers and earthquake occurrence in the central Virginia seismic zone. This correlation is examined both over a long-term span (57–92 years) and with regard to individual cases in which earthquakes have followed the occurrence of intense hydrological phenomena such as torrential rainfall or hurricanes. As we probe for a correlation between earthquake time series for central Virginia and the monthly precipitation series at hydrometeorological stations located in the zone, we observe that the best cross-correlation is obtained for a time period of 3 months. The same time period applies to certain historical earthquakes that were preceded by large amounts of precipitation. These results support the hydroseismicity hypothesis, which points to the role of water in the generation of intraplate seismicity.  相似文献   

17.
Spatial variation of seismicity parameters across India and adjoining areas   总被引：2，自引：2，他引：0  
An attempt has been made to quantify the variability in the seismic activity rate across the whole of India and adjoining areas (0–45°N and 60–105°E) using earthquake database compiled from various sources. Both historical and instrumental data were compiled and the complete catalog of Indian earthquakes till 2010 has been prepared. Region-specific earthquake magnitude scaling relations correlating different magnitude scales were achieved to develop a homogenous earthquake catalog for the region in unified moment magnitude scale. The dependent events (75.3%) in the raw catalog have been removed and the effect of aftershocks on the variation of b value has been quantified. The study area was divided into 2,025 grid points (1°×1°) and the spatial variation of the seismicity across the region have been analyzed considering all the events within 300 km radius from each grid point. A significant decrease in seismic b value was seen when declustered catalog was used which illustrates that a larger proportion of dependent events in the earthquake catalog are related to lower magnitude events. A list of 203,448 earthquakes (including aftershocks and foreshocks) occurred in the region covering the period from 250 B.C. to 2010 A.D. with all available details is uploaded in the website .  相似文献   

18.
We present the first systematic exploration of earth tides-seismicity correlation in northwestern South America, with a special emphasis in Colombia. For this purpose, we use a dataset of ∼167,000 earthquakes, gathered by the Colombian Seismological Network between 1993 and 2017. Most of the events are intermediate-depth earthquakes from the Bucaramanga seismic nest and the Cauca seismic cluster. For this purpose, we implemented a novel approach for the calculation of tidal phases that considers the relative positions of the Earth-Moon-Sun system at the time of the events. After applying the standard Schuster test to the whole dataset and to several earthquake samples (classified by time, location, magnitude and depth), we found strong correlation anomalies with the diurnal and monthly components of the tide (global log(p) values around −7.0 for the diurnal constituent and −12.1 for the monthly constituent), especially for the intermediate depth events. These anomalies suggest that around 16% of the deep earthquakes in Colombia may be triggered by tides, especially when the monthly phase is between 350°-10°. We attribute our positive results, which favor the tidal-triggering hypothesis, in contrast to previous negative ones to: 1) the size of our dataset, and 2) the method we used to calculate tidal phases. Anyone willing to reproduce our results or to apply our methodology to custom datasets can use the public information system tQuakes that we developed for this work.  相似文献   

19.
傅征祥  刘杰  王晓青  郝平  吕梅梅 《地学前缘》2003,10(Z1):112-117
中国大陆西部及邻区是全球 8级大地震最为活跃的地区之一。自 180 0年以来该区板内 8级大地震共发生了 16次 ,2 0 0 1年昆仑山口西 8.1级大地震 (36 .1°N ,90 .9°E)是在 195 7年蒙古 8.3级大地震之后 4 4a发生的。研究表明该区 8级大地震的活动过程可能存在相对平静 (1812— 190 2年 )和相对活跃 (190 3— 195 7年 )交替的幕式或轮回过程的性质。 195 7年蒙古地震之后可能是一次新的轮回开始 ,2 0 0 1年昆仑山口西地震是新轮回的第二次地震 ,按照轮回过程中事件发生频度是时间的指数函数关系的假定 ,该区下一次 8级大地震可能约在 2 0 2 6年发生。如果假定该过程相当接近泊松过程。那么 ,在 2 0 0 5 ,2 0 10年和 2 0 15年前至少发生一次 8级大地震的泊松概率 ,分别是 0 .2 9,0 .5 3和 0 .70。  相似文献   

20.
以2001—2011年美国NOAA长波辐射数据为背景数据,利用涡度背景场法研究2010年9月3日新西兰南岛M7.1级地震前后卫星长波辐射数据变化特征。结果表明,地震当月在震中西南侧出现显著的长波辐射异常变化,这种变化在全年各月及2001—2011年11年历年同月变化中都是最为显著的,认为其是本次地震的1次映震表现。用同样方法对区内2001—2011年11年间发生6次7.0级以上地震的长波辐射数据进行分析,结果在3次陆地地震发震前都检测到了长波辐射异常变化,而海域地震前则未发现这种现象。检索前人的相关研究结果,发现仅有2次海域地震(2004年12月26日印度尼西亚苏门答腊西北海域8.7级地震和2010年1月12日海地7.0级地震)前有长波辐射异常变化的报道,而根据全球云量分布资料显示,这2个地震所发生的区域是全球洋面云量分布最少的2个区域,而新西兰地震发生的区域位于全球洋面云量分布最多的区域。因此,认为由于水汽和云层对地表红外辐射的强吸收作用,长波辐射捕捉陆地地震红外辐射异常变化更加灵敏,对陆地地震的映震效能要强于海洋地震。  相似文献   

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