共查询到20条相似文献，搜索用时 134 毫秒
1.
试论1303年山西8级大震的几个问题 总被引：1，自引：0，他引：1
1303年山西汾河中游地区发生的强烈地震,是我国根据现有历史资料所能确定的第一个8级地震。本文根据历史文献和地震考古资料,主要讨论本次大震的历史依据;大震前后山西地震带的地震活动;大震的震害及其评价;宏观震中的可能位置及其命名等问题。经过分析,本次大震宏观震中的可能位置当在霍州城(今霍县城)附近;鉴于目前的认识尚不统一,可将本次大震称之为1303年山西汾河8级地震。同时指出地震史料和地震考古在历史地震研究中具有的重要作用;深入研究这次8级强震取得新的突破,所急待解决的几个关键课题。 相似文献
2.
1303年洪洞8级大震和1695年临汾7 级地震给山西尤其是临汾地区的人民带来了深重的灾难和难以磨灭的记忆,特别是洪洞地震,造成的灾害之大,民众伤亡之重,受灾地域之广,世界上和中国历史上均属罕见。1995年我在甘肃张掖参观当地的名胜——大佛寺时,据讲解员讲解,大佛寺历史上只遭受过2次大的破坏,其中一次就是1303年山西的洪洞地震。地震后进行了重修,并把重修大佛寺的经过用一块铜牌记载后放在大佛的肚子里面,“文革”中红卫兵把这块铜牌从大佛肚子里挖出后而得以问世,现在这块铜牌仍保存在大佛寺内。张掖离洪洞1500km,足见洪洞地震的影… 相似文献
3.
通过查阅宁夏6级以上地震的历史记载和各版地震目录,对历史资料进行了收集和整理,并对固原6级以上的历史地震进行实地考证。最后通过研究分析对部分历史地震参数作出复核和校订。 相似文献
4.
5.
6.
1500年宜良地震地表形变带的考证 总被引：2，自引：0，他引：2
据历史记载１５００年在宜良一带发生了一次强烈地震，由前人对该次地震无较详细的现 场实地考查资料，因此对这次地震认识说法不一。１９９２年作者对该次地震进行了实地考证。发现和确认了这次地震十分丰富的地震地表形变带，现存长度达８１公里，最大左旋水平位错量９至１１米。研究结果表明该次地震的发震构造为小新街－徐家渡断裂，震级接近８级。 相似文献
7.
8.
丽江7.0级地震地表破裂与形变特征 总被引：11，自引：3，他引：11
丽江７．０级地震序列发生在该地区属次级构造的断裂上，而且这次地震的烈度分布，地表破坏分布和强余震分布都表现了异常不均匀性。根据大震震害损失评估调查和大震现场地面破坏调查取得的资料，对上述异常现象的原因进行了初步分析，认为主震发震构造为玉龙山山前近南北向断裂，但其破裂过程可能存在“跳跃”和偏转。 相似文献
9.
1556年华县地震历史记载是中国历史记载最为丰富的地震之一,本文从这些历史地震记载中提取研究了对地震科学的价值,包括：（1）从“地旋运”记载启迪在大震前人感地旋可作为临震预警的指标;（2）从历史地震记载中综合得出大震前地震动由小到大的时间;（3）大震前旱震关系的中期前兆;（4）大震前汾河地堑中的中强地震活跃;（5）渭河盆地地震发生时间的600年周期;（6）历史地震发生时间的“三性法”分布指征;（7）华县大地震指征的烈度区划观点的验证,华县大地震揭示的烈度不对称性等。以及对秦可大《地震记》的科学意义及历史地位做了肯定性的研究与讨论。 相似文献
10.
11.
阪神·淡路大震灾后 ,日本着手对原有的地震观测体制作彻底改革 ,多项全国性配置地震计的计划同时开始启动。地震引起的地面晃动的程度不尽相同 ,无感微小地震引发的晃动仅有 0 .0 0 1 μm,频率为1 0 Hz;巨大地震引起的地面晃动的幅度高达 2～ 3 m,周期也有几十秒。虽说都称之为地震计 ,但由于地震动的振幅和频率涉及的范围太大 ,所以应针对观测对象选用不同类型的地震计。下面介绍不同类型的观测网。1 强震观测网 ( K- NET)无论大地有多大的晃动都能将其准确记录下来的地震计称之为强震计。它构造坚实 ,信号明确 ,通常设置在地表 ,对了… 相似文献
12.
Michael O. Garcia Diane Hanano Ashton Flinders Dominique Weis Garrett Ito Mark D. Kurz 《Bulletin of Volcanology》2012,74(6):1445-1463
The size, shape, and magmatic history of the most recently discovered shield volcano in the Hawaiian Islands, Mahukona, have been controversial. Mahukona corresponds to what was thought to be a gap in the paired sequence (Loa and Kea trends) of younger Hawaiian volcanoes (<4?Ma). Here, we present the results of marine expeditions to Mahukona where new bathymetry, sidescan sonar, gravity data, and lava samples were collected to address these controversies. Modeling of bathymetric and gravity data indicate that Mahukona is one of the smallest Hawaiian volcanoes (～6,000?km3) and that its magmatic system was not focused in a long-lived central reservoir like most other Hawaiian volcanoes. This lack of a long-lived magmatic reservoir is reflected by the absence of a central residual gravity high and the random distribution of cones on Mahukona Volcano. Our reconstructed subsidence history for Mahukona suggests it grew to at least ～270?m below sea level but probably did not form an island. New 40Ar–39Ar plateau ages range from 350 to 654?ka providing temporal constraints for Mahukona’s post-shield and shield stages of volcanism, which ended prematurely. Mahukona post-shield lavas have high 3He/4He ratios (16–21?Ra), which have not been observed in post-shield lavas from other Hawaiian volcanoes. Lava compositions range widely at Mahukona, including Pb isotopic values that straddle the boundary between Kea and Loa sequences of volcanoes. The compositional diversity of Mahukona lavas may be related to its relatively small size (less extensive melting) and the absence of a central magma reservoir where magmas would have been homogenized. 相似文献
13.
14.
15.
In this study, we have checked the location and focal depth of the Yecheng earthquake (m b = 6.0, maximum intensity VII) of February 14, 1980. The result shows that this is an intermediate event with a focal depth of 90 km. The microepicenter is located at 36. 4°N, 76, 9°E, while the macroepicenter is at 37.3°N, 76.9°E, 90 km to the north of the microepicenter. This is the first destructive intermediate event in China which led to a damage as severe as of intensity VII. The focal mechanism of the event is determined to be of thrust type. Combined with the analysis of seismological and geological data in surrounding area, the possible relation between the event and plate movement has been discussed. The result in this paper indicates that in some particular place, the destructive effect of intermediate event should be considered in seismic hazard assessment. 相似文献
16.
17.
In this study, we experimentally established the relationship between physical properties, vitrinite reflectance, and microstructure of coal, Taiyuan Formation, Qinshui Basin, China using representative coal samples collected from three different mines via the rock mechanics testing system (MTS). We analyzed the organic macerals, vitrinite reflectance, and microstructure of 11 coal samples using petrography and scanning electron microscopy (SEM). The experimental results suggest that (1) the elastic parameters can be described by linear equations, (2) both P-and S-wave velocities display anisotropy, (3) the anisotropy negatively correlates with vitrinite reflectance, and (4) the acoustic velocities and Young’s modulus are negatively correlated with the volume of micropores. The derived empirical equations can be used in the forward modeling and seismic inversion of physical properties of coal for improving the coal-bed methane (CBM) reservoir characterization. 相似文献
18.
19.
Abu Sayeed Shafiuddin Ahmed Mohammad Belal Hossain Saad Mohammad Omar Faruque Babu Moshiur Rahman Jun Sun Mohammad Shafiqul Islam Sarker 《国际泥沙研究》2022,37(1):83-96
Sediment samples from the Gomti River basin were investigated to determine and evaluate trace metal concentrations,their biological effect,and potential ecological and human health risks for adults and children.The mean concentrations of trace metals were organized in the descending order of mercury(Hg)(0.08 mg/kg)>chromium(Cr)(0.06 mg/kg)>lead(Pb)(0.05 mg/kg)>arsenic(As)(0.02 mg/kg)>cadmium(Cd)(0.01 mg/kg).The current study illustrated that metals were attributed to the area from natural sources and different anthropogenic sources especially from industries.However,the concentration levels were lower than the sediment quality guidelines(SQGs)based on the effect-range classifications of threshold effect concentration(TEC)and probable effect concentration(PEC).Therefore,the concentration of the elements showed no adverse biological effects on aquatic organisms.The evaluated potential ecological risk index also revealed the low toxicity to the aquatic environment.Moreover,the applied sediment quality indices,geo-accumulation index(Igeo),contamination factor(CF),and contamination severity index(CSI)suggested that the contamination levels of the elements were in the acceptable range,and the contamination had not notably impacted on the sediment quality.The risk index(HI)concerning age groups was significantly less than the threshold limit of 1 indicating that the contamination had no non-carcinogenic risk effect.The total carcinogenic risk(TCR)was less than a risk value of 1×104.Hence,the current study suggests that immediate remediation is not required due to an absence of alarming conditions in the study area.Proper monitoring of the attribution of the metal elements should be done for the betterment of human and environmental health。 相似文献
20.
Seismic data collected at four volcanoes in Central America during 1973 and 1974 indicate three sources of seismicity: regional
earthquakes with hypocentral distances greater than 80 km, earthquakes within 40 km of each volcano, and seismic activity
originating at the volcanoes due to eruptive processes. Regional earthquakes generated by the underthrusting and subduction
of the Cocos Plate beneath the Caribbean Plate are the most prominent seismic feature in Central America. Earthquakes in the
vicinity of the volcanoes occur on faults that appear to be related to volcano formation. Faulting near Fuego and Pacaya volcanoes
in Guatemala is more complex due to motion on a major E-W striking transform plate boundary 40 km north of the volcanoes.
Volcanic activity produces different kinds of seismic signatures. Shallow tectonic or A-type events originate on nearby faults
and occur both singly and in swarms. There are typically from 0 to 6 A-type events per day withb value of about 1.3. At very shallow depths beneath Pacaya, Izalco, and San Cristobal large numbers of low-frequency or B-type
events are recorded with predominant frequencies between 2.5 and 4.5 Hz and withb values of 1.7 to 2.9. The relative number of B-type events appears to be related to the eruptive states of the volcanoes;
the more active volcanoes have higher levels of seismicity. At Fuego Volcano, however, low-frequency events have unusually
long codas and appear to be similar to tremor. High-amplitude volcanic tremor is recorded at Fuego, Pacaya, and San Cristobal
during eruptive periods. Large explosion earthquakes at Fuego are well recorded at five stations and yield information on
near-surface seismic wave velocities (α=3.0±0.2 km/sec.). 相似文献