测震记录仪时间记录系统常见误差分析

本文讨论我国现阶段,测震台站常用测震仪器的时间记录各环节误差的产生、大小的估计及注意事项。     

以全球观点推进和参与地震科学研究

叙述了地震科学的发展和与地震科学发展有关的问题,提出了在现今地震科学发展的形势下,地震科研人员和管理人员应密切关注的主要问题,指出了科研人员和管理人员的视野应朝何方面扩展和延伸,得出地球科学的研究必须以全球观点予以推进和参与才有出路的结论。     

浙江省常山县上震旦统西峰寺组碳酸盐的δ13C和δ18O测定

 作者对浙江省常山县三里亭北九家坞的上震旦统剖面的碳酸盐系统采集的54个样品,作了碳、氧稳定同位素的分析。其中δ¹³C除4个外几乎全为正值,平均值2.16%,这与前人提到过的文德期以δ¹³C负迁移为特征的结论不符。离散变为9.0。最大负峰值出现在剖面近中部的磷块岩层中,可能与海流状况的剧变有关。δ¹⁸O除最末两个为小的正值外,几乎全为负值。     

辽东海岸带黄土

本文论述了辽东海岸带黄土的成因,它主要由低空气流搬运的近源物质组成,其次为高空气流携带的内陆远源物质,主要物源地是辽东湾。冰期时,海平面下降,辽东湾干口渤海裸露成陆而发生沙漠化,海底沉积物经强劲的西北风作用,被搬运到东侧海岸带沉降下来,与大气环流系统自内陆携带而至的风尘物质混合在一起,形成海岸带黄土。     

The Coastal Zone Loess of the Liaodong Peninsula, Liaoning Province

This Paper discusses the origin of the Coastal Zone Loess on the Liaodong Peninsula, Liaoning Province.The loess is composed mainly of proximal materials transported by low-altitude air flow and less commonly ofinland distal materials carried by high-altitude air flow. The main provenance is the Liaodong Bay. When thesea level declined during glacial period, the bottoms of the Liaodong Bay and Bohai Sea emerged, wheredesertization occurred. As a result, submarine sediments were transported by strong northwesterly winds to theeastern coastal zone of the peninsula and deposited there. These materials mixed with the windblown dust car-ried by atmospheric circulation from the interior of the continent, forming the loess.     

常德市城区工程地质特征

常德市城区包括武陵区、武陵镇、德山,它位于洞庭湖淤积平原上,工程地质条件复杂,为多土层结构,软土层发育。常德为7度地震区。据土层特征,标准贯入,动、静三轴试验结果,在武陵区、武陵镇一带,轻亚粘土31.1％有液化,淤泥质轻亚粘土55.4％有液化,粉砂—细砂层60.5％有液化。据此对常德市城区的工程勘察、地基基础类型提出了一些具体看法和建议。     

The deep and shallow structure,composition and its relation to earthquakes in Chaoyang — Yixian seismic region

This paper describes synthetically the seismic activity, deep and shallow structures and rock dynamic features in and near Chaoyang—Yixian region. It is supposed that there is a low velocity layer in middle crust and the three-layered crustal velocities are all lower than that in both sides of the region. There exists uplifts of upper mantle and asthenosphere-low resistance layer. It is also studied the composition of matter of three-layered crust, low velocity layer, upper mantle and asthenosphere. In the end the direct relations between the deep and shallow structure, composition and the seismic activity and new activities of faults in this region are discussed.     

Soil amplification based on seismometer array and microtremor observations in Chiba,Japan

Soil amplification characteristics of earthquake ground motion were investigated in terms of peak ground acceleration and transfer function based on the Chiba array observation records. The amplification of peak ground acceleration occurred mostly at the top soft layer and was similar for the three components. The effects of non-linear response of soil deposits on the transfer function were examined. Transfer functions calculated by ensemble average were close for the two horizontal components while those obtained from a smoothing operation were generally different. Both the transfer functions from the ensemble average and the smoothing operation underestimated the gain factor around the natural frequencies. A two-step smoothing procedure was proposed and a rotary spectrum was used to improve the estimation of the transfer function. Microtremors were observed at the locations of the boreholes where seismometers are buried. The power spectrum and spatial coherency of the microtremors were compared with those of the earthquake ground motion. Emphasis was placed on the wavetypes which dominated the peaks in the power spectra.     

Orientation error estimation of buried seismographs in array observation

Array observation is an efficient tool to investigate various characteristics of earthquake ground motion. However, seismographs used in arrays may involve unexpected errors in their orientations. Methods of orientation error estimation were developed in three-dimensional space by comparing recorded ground motions at a reference point with those at a checking point. A maximum cross-correlation method and a maximum coherence method were proposed and their accuracy was demonstrated. The earthquake ground motions recorded in the Chiba array and in two other arrays were used in numerical examples. Non-trivial orientation errors were detected for all these arrays. The cross-correlation coefficients and the coherence values between two points increased significantly by correcting the estimated orientation errors.     

EXTRACTION OF THE STANDARD ENTHALPY OF FORMATION OF MINERALS FROM REVERSED EXPERIMENTAL DATA WITH INS

An improvement on the new method of Intervalhalving-Scanning (INS) proposed by the senior author for derivation of thermodynamic properties of minerals from reversed experiment (REP) data has been made in the present work. The treatment of the REP data of 6 reactions in the system MgO-SiO_2-H_2O and the derivation of △_(?)H(?) (298. 15K) for minerals Talc,Forsterite and Anthophyllite are chosen as an example for demonstration of the application of the method.INS is quite different from all the methods for the derivation in the literature and throughout based on thermodynamic principles and equations so that its thermodynamical validity is thoroughgoing.