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741.
742.
南海北部沉积物特征及其对珠江演变的响应 总被引:1,自引:0,他引:1
采用沉积地球化学、沉积物矿物成分分析等手段研究发现,自渐新世以来,南海北部沉积物成分具有阶段性改变的特征.在早渐新世,沉积物反映出其母岩以花岗岩和区域变质岩为主;到晚渐新世,母岩中区域变质岩类型消失,而以花岗岩、沉积岩和接触变质岩为特征;进入中新世,沉积物主要反映出碳酸盐岩等沉积岩为主的源区特点.这种沉积物成分演变特征与南海北部盆地基底及珠江流域不同区域物质组成特征极为一致,反映出珠江流域演化与南海北部沉积充填之间的对应关系.因此,通过这种研究方法,可以更好地理解32Ma以来南海北部沉积物成分发生改变的原因.同时,可以通过对比南海北部古珠江来源沉积物各时期的成分特点,建立珠江流域的侵蚀-搬运-沉积过程,探讨珠江流域演化历史. 相似文献
743.
By substituting rock skeleton modulus expressions into Gassmann approximate fluid equation, we obtain a seismic porosity inversion equation. However, conventional rock skeleton models and their expressions are quite different from each other, resuling in different seismic porosity inversion equations, potentially leading to difficulties in correctly applying them and evaluating their results. In response to this, a uniform relation with two adjusting parameters suitable for all rock skeleton models is established from an analysis and comparison of various conventional rock skeleton models and their expressions including the Eshelby-Walsh, Pride, Geertsma, Nur, Keys-Xu, and Krief models. By giving the two adjusting parameters specific values, different rock skeleton models with specific physical characteristics can be generated. This allows us to select the most appropriate rock skeleton model based on geological and geophysical conditions, and to develop more wise seismic porosity inversion. As an example of using this method for hydrocarbon prediction and fluid identification, we apply this improved porosity inversion, associated with rock physical data and well log data, to the ZJ basin. Research shows that the existence of an abundant hydrocarbon reservoir is dependent on a moderate porosity range, which means we can use the results of seismic porosity inversion to identify oil reservoirs and dry or water-saturated reservoirs. The seismic inversion results are closely correspond to well log porosity curves in the ZJ area, indicating that the uniform relations and inversion methods proposed in this paper are reliable and effective. 相似文献
744.
XueWu Cheng Yong Yang ZeLong Wang FaQuan Li GuoTao Yang ZhengYu Zhao Wei Gong JiHong Wang Xiong Hu Xin Lin XiaoCheng Wu ShaLei Song ShunSheng Gong 《中国科学:地球科学(英文版)》2016,59(2):418-424
During the total solar eclipse on July 22, 2009 in Wuhan, the joint observation test of Na layer and ionosphere was conducted by using the daytime observation atmospheric lidar and the GPS ionosphere detector. The results show that the full width at half maximum (FWHM) of Na layer density slightly narrowed during the total solar eclipse and broadened after the eclipse, while the height of Na peak slightly decreased in the eclipse and increased after the eclipse. These implying that Na layer changes reflect the rapid process of sunrise and sunset. The ionosphere total electron content (TEC) and the sky background light noise also presented an obvious fluctuation characteristic with the changes of solar irradiation during the process of total solar eclipse. The difference lies in that the changes of FWHM of Na layer atoms are much slower than that of ionosphere, the reason for this might be that the Na layer, after being disturbed by the total solar eclipse, will generate a series of complicated photochemical reactions and momentum transport processes, and then recombine the Na atoms. The Na atoms to be detected by the lidar need a lag process, which rightly conforms to the theoretical simulated results. 相似文献
745.
��BP�����缼��̽���봨����ǰ�����NmF2�쳣�Ŷ� 总被引:2,自引:0,他引:2
????UCAR??????????F2???????????????NmF2??????????????缼???????????????NmF2???????????DOY???????LT??????LON??γ??LAT??F10.7????????FLUX???????????NmF2???????????????????NmF2????????ο????????????????????????????2008??5??12????7.9??????????и??????NmF2???????6??4??6??8?????С?30%???????3??2??9??10????????????40%?? 相似文献
746.
????GPS?????????????(PWV)??????????????????????????SA????????????????GPS???????????????????GPS????????????????????????θ???????????????ù??????????????????????????С??100 m???????????????????μ????????????Saastamoinen?????????????????????????????????IGS???BJFS??KUNM??LHAZ??TWTF??????????????????????????????????GPS PWV????????????????????RS PWV?????ж???????????????????????????θ???????????????????GPS PWV??RS PWV??????????????1~3 mm?????????????????????????????????GPS????PWV?? 相似文献
747.
???????????????????????????????????????б??????????t??????????????????????????????????????????????????????????????????????????????????????DEM?? 相似文献
748.
SHAN Bin XIONG Xiong ZHENG Yong & DIAO FaQi Key Laboratory of Dynamical Geodesy 《中国科学D辑(英文版)》2009,(5)
On May 12,2008,a magnitude 7.9 earthquake ruptured the Longmenshan fault system in Sichuan Province,China,collapsing buildings and killing tens of thousands people.As predicted,aftershocks may last for at least one year,and moreover,large aftershocks are likely to occur.Therefore,it is critical to outline the areas with potential aftershocks before reconstruction and resettling people as to avoid future disasters.It is demonstrated that the redistribution of stress induced by an earthquake should trigger su... 相似文献
749.
2008年5月12日我国四川省汶川县发生了8.0级大地震,基于中国地壳运动观测网(CMONOC)的GPS观测数据,解算得到了震中上空附近的电离层VTEC;以VTEC的滑动均值为背景参考值,以2倍均方差作为误差限值,对临震一个月的VTEC 资料进行了处理分析.结果显示,在震前多次出现VTEC的异常扰动,其中4月29日、5月6——7日为异常减少,5月9日为异常增加,而且电离层VTEC的异常驼峰有向磁赤道漂移的趋势.由于距离发震时刻较近,排除其它因素后可能源于此次地震引起的电离层效应. 相似文献
750.
文中对腾冲火山区1998—2004年水准及重力观测资料进行了分析,发现垂直形变量大多在±10mm之内,重力变化为几十μGal,火山锥体和断层附近点位活动异常较大,可综合应用多源mogi模型和断层模型解释,断层的活动可使相邻测点的形变方向相反;垂直形变和重力的逐年变化表明火山岩浆处于一种活动状态。将火山区点位各时间段的重力梯度展布在形变-重力关系解释图中,发现数据主要落在Ⅰ、Ⅱ、Ⅳ和Ⅴ区,结合形变量对压力源等效体积的估算,初步认为火山区岩浆目前活动程度较低,暂没有喷发的危险 相似文献