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Earthquake Engineering and Engineering Vibration 2020年第2期19卷 321-333页

作者： Mehmet Zakir Kanbur Ali Silahtar Gokhan Aktan Suleyman Demirel University Engineering FacultyDepartment of Geophysical EngineeringIspartaTurkey

This study aimed to investigate the site characterization of the Senirkent Basin(Isparta)by using the microtremor(H/V)and surface wave analysis(ReMi)*** district,which is located on the foothill of the Kap?Mountain,are prone to seismic and landslide *** the last landslip disaster(1995),the city has continued to develop on the alluvial *** microtremor data collected at 41 stations were *** predominant frequency and the amplification of the soil were found to be in the range of 1.8–6.6 Hz and 0.8–6.8,*** are 4.0-6.8 Hz and 1-2.5 around the slope of the Kap?Mountain and 0.8-3.6 Hz and 3.0-6.6 at alluvium deposits of the *** ReMi data collected along 41 profiles were analyzed to obtain a Vs30 *** soil classifications were done by using Vs30 values according to NEHRP soil classification *** results showed that the southern area of the study had better soil conditions with Vs30 between 360-1160 m/s and soil class between C and *** alluvium deposits on the north are relatively low with Vs30 in the range of 260-360 m/s and soil class D.

关键词： site characterization microtremor surface waves Vs30 Z1.0

Three－dimensional　Global　Scale　Permanent－wave　Solutions　of　the　Nonlinear　Quasigeostrophic　Potential　Vorticity　Equation　and　Energy　Dispersion

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Advances in Atmospheric Sciences 1995年第4期12卷 387-404页

作者： H.L. Kuo (department of geophysical Sciences, University of Chicago, Chicago, IL 60637) department of geophysical Sciences University of Chicago

The three-dimensional nonlinear quasi-geostrophic potential vorticity equation is reduced to a linear form in the stream function in spherical coordinates for the permanent wave solutions consisting of zonal wavenumbers from 0 to n and rn vertical components with a given degree *** equation is solved by treating the coefficient of the Coriolis parameter square in the equation as the eigenvalue both for sinusoidal and hyperbolic variations in vertical direction. It is found that these solutions can represent the observed long term flow patterns at the surface and aloft over the globe closely. In addition, the sinusoidal vertical solutions with large eigenvalue G are trapped in low latitude,and the scales of these trapped modes are longer than 10 deg. lat. even for the top layer of the ocean and hence they are much larger than that given by the equatorial β-plane *** such baroclinic disturbances in the ocean can easily interact with those in the *** of the shallow water potential vorticity equation are treated in a similar manner but with the effective depth H=RT/g taken as limited within a small range for the *** propagation of the flow energy of the wave packet consisting of more than one degree is found to be along the great circle around the globe both for barotropic and for baroclinic flows in the atmosphere.

关键词： Finite amplitude potential vorticity solution General circulation Global scale energy dispersion

Availability of seismic vulnerability index(K_g) in the assessment of building damage in Van, Eastern Turkey

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Earthquake Engineering and Engineering Vibration 2020年第1期19卷 189-204页

作者： ismail Akkaya Van Yüzüncü Yil University Engineering FacultyDepartment of Geophysical Engineering

The seismic vulnerability index(Kg) is a parameter that depends on the dynamic properties of soil. With this parameter, it is possible to evaluate the vulnerability of a point-based site under strong ground motion. Since it is related to the natural vibration period and amplification factor, the parameter can be calculated for both soil and structure. In this study, HVSR microtremor measurements are recorded at more than 200 points in the Van region to generate a seismic vulnerability index map. After generating the map, it is determined that the hazard potential and seismic vulnerability index is high at the sites close to Van Lake and at the densely populated city center. Damage information of the buildings investigated after the 2011 Van earthquakes(Mw = 7.1) are placed on the seismic vulnerability index map and it is realized that there may be a correlation between the damage and the seismic vulnerability index. There is a high correlation, approximately 80 percent, between the damage rate map based on the damaged building data and the K_g values. In addition, vulnerability indexes of buildings are calculated and the effect of local soil conditions and building properties on the damage levels are determined. From the results of this study and the site observations after the 2011 Van earthquakes, it is found that structural damage is not only structure-dependent but is also related to the dynamic behavior of soil layers and local soil conditions.

关键词： seismic vulnerability index building damage HVSR soil-structure interaction

Modeling Biogeochemistry, the Key for Understanding Environmental Chemistry of a Semi-Arid Soil in Egypt

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Chinese Journal Of Geochemistry 2003年第2期22卷 150-155页

作者： Ahmed A. Melegy department of Geological and geophysical Sciences National Research CentreDokki

Modeling geochemistry of the studied Bahtim catchment in Egypt provides a powerful tool for untangling various connections and feedbacks between atmospheric inputs, vegetation, soil and hydrology within the system. The biogeochemical PROFILE model was used to study the integrated environmental monitoring of different environmental compartments as well as calculating geochemical weathering rate. The model is in steady state and includes multi-layers which have the mineralogical, physical and chemical attributes measured for individual soil layers. In this study, the base cations (Ca+{2+}, Mg+{2+}, Na++, K++) are produced from the minerals through chemical weathering. The total chemical weathering rate of base cations is 6.5 keq+{-1}·ha+{-1}·a+{-1}. In addition, the output results indicate that a small amount of dark minerals like hornblende, pyroxene and plagioclase largely contribute the field weathering rate in Egyptian Vertisols.

关键词：生物地球化学环境化学埃及土壤植被大气水文学环境监测侵蚀速率变性土

Effects of effluent organic matters on endocrine disrupting chemical removal by ultrafiltration and ozonation in synthetic secondary effluent

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Journal of Environmental Sciences 2019年第2期31卷 57-64页

作者： Xiurong Si Zunfang Hu Ding Ding Xu Fu Civil Engineering department North China Institute of Aerospace Engineering Shandong Institute of geophysical and Geochemical Exploration

Endocrine disrupting chemicals(EDCs) in the secondary effluent discharged from wastewater treatment plants are of great concern when water reuse is intended. Ozonation and ultrafiltration(UF) are powerful technologies reported to eliminate EDCs. Due to the importance of effluent organic matters(EfOMs) in secondary effluent, the effects of three kinds of EfOM on the treatment of five EDCs using ozonation and UF were investigated. The three kinds of EfOM studied were humic acid sodium salt(NaAH), bovine serum albumin(BSA)and sodium alginate(NaAg); and the five EDCs were estrone, 17β-estradiol, estriol, 17α-ethynyl estradiol and bisphenol A. The results showed that EfOM accelerated the decay rate of ozone and inhibited the degradation efficiency of EDCs by ozonation in the order NaAH > BSA > *** ultraviolet absorbance at 280 nm(UVA_(280)) has potential for use as a surrogate indicator to assess EDC removal via ozonation without conducting difficult EDC analyses. When the decline in UVA_(280) exceeded 18%, the five EDCs had been completely removed. The UF behavior of NaAH,BSA and NaAg was found to follow the cake filtration law. The fouling potential of EfOM followed the order NaAg > NaAH > BSA; while EfOM on the membrane surface enhanced EDC removal in the order NaAH > BSA > NaAg. The mean retention rate of the membrane was increased by 24%, 10% and 8%, respectively. The properties of EDCs and EfOM cakes both influenced the EDC removal rates due to adsorption, size exclusion and charge attraction.

关键词： Endocrine disrupting chemicals Ultrafiltration Ozonation Effluent organic matters Secondary effluent

Clustering Seismic Activities Using Linear and Nonlinear Discriminant Analysis

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Journal of Earth Science 2014年第1期25卷 140-145页

作者： H Serdar Kuyuk Eray Yildirim Emrah Dogan Gunduz Horasan department of Civil Engineering Faculty of EngineeringSakarya University department of geophysical Engineering Faculty of EngineeringSakarya University

Identification and classification of different seismo-tectonic events with similar character- istics in a region of interest is one of the most important subjects in seismic hazard studies. In this study, linear and nonlinear discriminant analyses have been applied to classify seismic events in the vicinity of Istanbul. The vertical components of the digital velocity seismograms are used for seismic events with magnitude （Md） between 1.8 and 3.0 that occurred between 2001 and 2004. Two, time dependent pa- rameters, complexity and S/P peak amplitude ratio are selected as predictands. Linear, quadratic, diag- linear and diagquadratic discriminant functions are investigated. Accuracy of methods with an addi- tional adjusted quadratic models are 96.6%, 96.6%, 95.5%, 96.6%, and 97.6%, respectively with a vari- ous misclassified rate for each class. The performances of models are justified with cross validation and resubstitution error. Although all models remarkably well performed, adjusted quadratic function achieved the best success rate with just 4 misclassified events out of 179, even better compared to com- plex methods such as, self organizing method, k-means, Gaussion mixture models that applied to same dataset in literature.

关键词： discriminant analysis clustering analysis self organizing map k-means Gaussion mix- ture models.

Boninitic geochemical characteristics of high-Mg mafic dykes from the Singhbhum Granitoid Complex,Eastern India

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Chinese Journal Of Geochemistry 2015年第2期34卷 241-251页

作者： Akhtar R.Mir Shabber H.Alvi V.Balaram department of Earth Sciences University of Kashmir department of Geology Aligarh Muslim University National geophysical Research Institute

The high-Mg mafic dykes from the Singhbhum Granitoid Complex in East India have geochemical characteristics[e.g.,enrichment of the large ion lithophile elements and light rare earth elements(LREEs) relative to high field strength elements(HFSEs):high-MgO(>8%),high-SiO_2(>52%),low-TiO_2(0.58)]similar to those found in boninitic/noritic *** high percentage of orthopyroxene as a mafic mineral and of plagioclase as a felsic mineral,and normative hypersthene content greater than diopside content are also indications of their boninitic/noritic *** a triangular diagram of MgO-CaO-Al_2O_3 and on binary diagrams of Ti/V vs Ti/Sc and TiO_2 vs Zr,these samples show geochemical similarities with Phanerozoic boninites and Paleoproterozoic high-Mg *** major and trace element variation diagrams,these dykes show a normal crystallization trend and their Nb/La(<0.5) and Nb/Ce(<0.21) values lower than average bulk crust(0.69 and0.33,respectively) suggest no crustal *** low values of Rb/Sr(0.11-0.41) and Rb/Ba(0.10-0.27)also suggest little or no effect of post magmatic *** TiO_2(0.27-0.50),Al_2O_3/TiO_2(19.30-42.48),CaO/TiO_2(12.96-32.52),and Ti/V(12-18) values indicate derivation from a depleted mantle source under oxidizing conditions such as a mantle *** vs Zr modeling shows that the studied high-Mg dykes were generated by25-30%melting of a refractory mantle *** of Rb,Th,U,Pb,Sr,and LREEs,and depletion of HFSEs—especially Nb,P,Ti,Zr—on primitive mantle—and chondrite-normalized spider diagrams,respectively,are clear signals that the slab-derived component played an important role in the formation of melts for these rocks in a supra-subduction zone setting.

关键词：地球化学特征镁铁质花岗岩高镁印度轻稀土元素二氧化钛大楼

Multistage Deformation in the Northeastern Segment of the Jiangshao Fault (Suture) Belt: Constraints for the Relationship between the Yangtze Plate and the Cathaysia Old Land

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Acta Geologica Sinica(English Edition) 2013年第4期87卷 948-978页

作者： ZHANG Jin LI Jinyi XIAO Wenxia FENG Qianwen MA Zongjin Institute of Geology Chinese Academy of Geological Sciences department of Chang Qing geophysical Survey Geophysical Company Limited China National Petroleum Corporation Institute of Geology China Earthquake Administration

Multistage deformation events have occurred in the northeastern Jiangshao Fault （Suture） Belt. The earliest two are ductile deformation events. The first is the ca. 820 Ma top-to-the-northwest ductile thrusting, which directly resulted from the collision between the Cathaysia Old Land and the Chencai Arc （？） during the Late Neoproterozoic, and the Jiangnan Orogenic Belt that formed as the ocean closed between the Yangtze Plate and the jointed Cathaysia Old Land and the Chencai Arc due to continuous compression. The second is the ductile left-lateral strike-slipping that occurred in the latest Early Paleozoic. Since the Jinning period, all deformation events represent the reactivation or inversion of intraplate structures due to the collisions between the North China and Yangtze plates during the Triassic and between the Philippine Sea and Eurasian plates during the Cenozoic. In the Triassic, brittle right-lateral strike-slipping and subsequent top-to-the south thrusting occurred along the whole northeastern Jiangshao Fault Zone because of the collision between the North China and Yangtze plates. In the Late Mesozoic, regional extension took place across southeastern China. In the Cenozoic, the collision between the Philippine Sea and Eurasian plates resulted in brittle thrusts along the whole Jiangnan Old land in the Miocene. The Jiangshao Fault Belt is a weak zone in the crust with long history, and its reactivation is one of important characteristics of the deformation in South China; however, late-stage deformation events did not occur beyond the Jiangnan Old Land and most of them are parallel to the strike of the Old Land, which is similar to the Cenozoic deformation in Central Asia. In addition, the Jiangnan old Land is not a collisional boundary between the Yangtze Plate and Cathaysia Old Land in the Triassic.

关键词： intraplate deformation Jiangshao Fault (Suture) Belt Yangtze Plate Cathaysia Old Land,Jiangnan Old Land

Simulations of the 100-hPa South Asian High and Precipitation over East Asia with IPCC Coupled GCMs

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Advances in Atmospheric Sciences 2006年第3期23卷 375-390页

作者：周宁芳俞永强钱永甫 department of Atmospheric Sciences State Key Laboratory of Numerical Modeling for Atmospheric Sciences and geophysical Fluid Dynamics

The South Asian High （SAH） and precipitation over East Asia simulated by 11 coupled GCMs associated with the forthcoming Intergovernmental Panel on Climate Change＇s （IPCC） 4th Assessment Report are evaluated. The seasonal behavior of the SAH is presented for each model. Analyses of the results show that all models are able to reproduce the seasonal cycle of the SAH. Locations of the SAH center are also basically reproduced by these models. All models underestimate the intensity and the extension of coverage in summer. The anomalous SAH can be divided into east and west modes according to its longitudinal position in summer on the interannual timescale, and the composite anomalies of the observed precipitation for these two modes tend to have opposite signs over East Asia. However, only several coupled GCMs can simulate the relationship between rainfall and SAH similar to the observed one, which may be associated with the bias in simulation of the subtropical anticyclone over the West Pacific （SAWP） at 500 hPa. In fact, it is found that any coupled GCM, that can reproduce the reasonable summer mean state of SAWP and the southward （northward） withdrawal （extension） for the east （west） mode of SAH as compared to the observed, will also simulate similar rainfall anomaly patterns for the east and west SAH modes over East Asia. Further analysis indicates that the observed variations in the SAH, SAWP and rainfall are closely related to the sea surface temperature （SST） over the equatorial tropical Pacific. Particularly, some models cannot simulate the SAWP extending northward in the west mode and withdrawing southward in the east mode, which may be related to weak major E1 Nifio or La Nifia events. The abilities of the coupled GCMs to simulate the SAWP and ENSO events are associated partly with their ability to reproduce the observed relationship between SAH and the rainfall anomaly over East Asia.

关键词： South Asian High East Asian summer rainfall Coupled GCMs

Tectonomagmatic origin of some volcanic and sub-volcanic rocks from the Lower Benue rift, Nigeria

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Chinese Journal Of Geochemistry 2011年第4期30卷 507-522页

作者： Smart C. Obiora Nirmal S. Charan department of Geology University of Nigeria National geophysical Research Institute Geological Studies Division

Petrological and geochemical studies on some volcanic and sub-volcanic rocks from the Lower Benue rift indicate that they are basalts, basaltic and doleritic sills, trachybasalt and trachyte which generally belong to the alkali basalt series. The alkaline affinity is clearly evident in both their normative and modal mineral compositions, as well as their chemical compositions. The generally high fractionation indices [(La/Yb)N] are 7.06 to 17.65 for the basaltic rocks and 23.59 to 135. 35 for the trachytic rocks, against low values commonly seen in subalkaline (tholeiitic) series, with strong enrichments in the incompatible elements. All this strongly supports their alkaline affinity. The basaltic rocks are generally fine-grained and porphyritic, consisting of phenocrysts of clinopyroxene and olivine in the groundmass of the same minerals together with plagioclase. The clinopyroxene is either diopside or clinoenstatite. The trachyte consists of oligoclase, orthoclase, biotite, quartz and exhibits typical trachytic, flow structure. The basaltic and doleritic sills are commonly altered, with calcite and epidote as common alteration prod-ucts. This alteration, which is reflected in the erratic behaviour of K2O, MnO and P2O5 on Harker variation diagrams, high values of LOI, strong depletions in the more mobile LILE (Rb, K, Ba and Sr) and high Th/Ta ratios, is attributed to the effects of an aqueous fluid phase and crustal contamination. On the whole, the mineralogical, as well as major-, trace-elements and REE data suggest that the rocks are co-genetic and most likely derived from differentiation of an alkali olivine-basalt magma, generating through variable low degrees of partial melting of probably an enriched lithospheric (upper) mantle following an asthenospheric uplift (mantle plume or intumescence) with HIMU signa-tures in a within-plate continental rift tectonic setting. This corroborates earlier results obtained for the intrusive rocks in the region.

关键词：次火山岩裂谷构造岩浆起源岩石学尼日利亚粗面玄武岩玄武质岩石单斜辉石