共查询到20条相似文献，搜索用时 468 毫秒
1.
通过可控源音频大地电磁测深(CSAMT)、浅层地震和高密度电法地球物理探测手段建立的联合剖面对比,同时开展钻探工程及古地磁样品测试,对南口-孙河断裂带(北段)结构及活动性进行研究。南口-孙河断裂带(北段)由1条主断裂和1条次级断裂组成,断裂带宽约400m,表现为阶梯状断层,向上延伸至第四系。第四纪以来,断裂带活动显著,体现为松散层浅部引张的特点。根据断裂两盘第四纪以来各阶段累积垂直落差,计算出主断裂及次级断裂的活动速率。主断裂在早更新世、中更新世、晚更新世、全新世活动速率分别为0.161mm/a、0.072mm/a、0.468mm/a、0.52mm/a,次级断裂在早更新世、中更新世、晚更新世、全新世活动速率分别0.049mm/a、0.052mm/a、0.223mm/a、0.04mm/a。 相似文献
2.
沙湾断裂是珠江三角州北西向的主干断裂。为了查清其第四纪活动性,我们进行了1∶5万地质地貌填图、断层活动年代测定、氡气测量、浅层地震勘测和联合钻孔验证及构造解析等工作。第四纪地貌与断裂的耦合性及历史地震情况说明,沙湾断裂目前仍有一定活动性;地质调查及勘测未发现断裂切割第四系,氡气测量结果表明断裂目前活动性中等以下,说明沙湾断裂目前活动性较弱;年代测量结果表明断裂在中更新世中期至晚更新世前期活动性较强,晚更新世以后活动性渐弱,仅在南段南沙区大岗镇罗汉山发现晚于100 ka剖面。罗汉山构造解析实例说明三角洲局部地段仍受断裂活动控制处于拉张环境,但全新世以来活动性渐弱。综合研究认为,沙湾断裂目前仍有一定活动性,但活动性较弱。 相似文献
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作为郯庐断裂带北段主干的依兰-伊通断裂, 其新构造活动性与活动规律仍然存在不同的认识.本次工作通过详细的野外调查, 发现该断裂内活断层广泛存在, 由东、西两支北东走向的主干活断层构成, 沿着古近纪地堑边界断层发育.这些活断层主要呈破碎型结构, 多为逆右行平移活动.通过对这些活断层一系列实测擦痕反演应力场, 显示它们多是在东西向挤压中活动的, 而现今应力场转变为北东东-南西西向区域性挤压.依据本次野外观察与14 C定年, 并结合前人定年结果与近代地震分布, 表明依兰-伊通西支活断层的最新活动时代为全新世与晚更新世相间, 而东支活断层的最新活动时代主要为早-中更新世.依兰-伊通断裂内活断层显示了明显的差异性活动, 表现为西支的活动强度明显大于东支, 西支的最新活动时代皆晚于东支, 沿走向上活动性强、弱相间与最新活动时代不断变化, 以及近代地震活动不均一分布.它们沿走向上的分段性、差异性活动主要是因为被一系列北西向断层切断所致. 相似文献
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新疆博格达山北缘阜康南断裂带古牧地段晚第四纪活动特征 总被引：1，自引：0，他引：1
新疆博格达山北缘阜康南断裂带古牧地断裂段是发育在古牧地背斜北翼的逆冲断裂,由南倾的主干断裂和南侧的反冲断裂组成,晚第四纪以来断裂新活动性明显,地表形成一系列的地质地貌现象.文章在大红沟附近通过变形阶地测量、探槽开挖和热释光(TL)年代测定,获得古牧地断裂晚更新世末期以来的平均垂直滑动速率为0.27mm/a左右,全新世以来的平均垂直滑动速率为0.13～0.18mm/a,速率明显变小.古地震研究表明,古牧地断裂晚第四纪以来有过多次活动,最新一次古地震事件的垂直错距在1.4m左右,离逝时间已达8ka以上.古牧地断裂全新世以来的运动速率偏低,很可能意味着该断裂需要一次强震来释放存储的弹性应变,表明古牧地断裂具有很大的地震危险性. 相似文献
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北京顺义断裂第四纪活动性地球物理及钻孔综合探测证据 总被引：1，自引：0，他引：1
顺义断裂是北京平原区重要的隐伏断裂之一,其第四纪活动性及其对地表地裂缝地质灾害影响的研究是优化首都地区国土空间开发格局和防灾减灾体系建设的必要工作。针对隐伏断裂的复杂性特征,利用可控源音频大地电磁测深(CSAMT)、浅层人工地震、高密度电阻率法地球物理探测,以及钻孔地层剖面记录等方法,综合分析顺义断裂第四纪活动特征,结果表明：①顺义断裂走向NE,倾向SE,正断活动特征,为全新世活动断裂,北小营附近断裂上下盘早更新世、中更新世、晚更新世和全新世以来的垂直滑动速率分别为0. 23mm/a、0. 03 mm/a、0. 29 mm/a和0. 51 mm/a;②断裂第四纪以来时空存在明显差异,时间上,早更新世断裂活动性较强,中更新世活动弱,晚更新世活动性增强,全新世以来活动性最强,空间上,第四纪以来顺义断裂南段的活动性较北段强;③顺义断裂现今仍具有一定蠕滑活动特征,并对浅地表部地裂缝发育具有明显的控制作用,这可能是顺义地裂缝发育的主要原因。 相似文献
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九江地区第四系中典型地裂缝特征及构造意义 总被引：3，自引：0，他引：3
在九江地区开展断裂活动性调查中,发现了一些第四纪剖面中发育丰富的地裂缝。本文选择三个第四系中典型地裂缝出露剖面为研究材料,通过野外实测展开对剖面的地层序列、地裂缝的宏观和微观特征及地裂缝与区域断裂分布规律进行分析,有以下4点发现:1九江地区第四系中地裂缝形态特征多样,多呈"V"型,"倒V"型,"Y"型,"扫帚"型和"直线"型等;2地裂缝内均有充填物,充填物多呈灰白色、浅灰色条带,宽度不等,多呈上窄下宽,向上渐尖灭,向下未见底。地裂缝内充填物具有劈理化、压扁、挤压、拖拽等受力流变现象;3平面分布上,地裂缝出露剖面PM1位于九江-德安断裂NE末端,PM2位于襄樊-广济断裂SE末端,PM3位于城门山-范家铺断裂带中部,地裂缝出露剖面位置与九江地区区域性断裂展布和历史地震震中分布都具有高度相关性。同时,PM1、PM2和PM3三个剖面的主要地裂缝走向分别为NE、NW和NEE,与其高度相关的断裂走向也分别一致;4PM3剖面发育一条第四纪断层,断层产状为145°∠68°,显示正断性质,最大错据可达1m。综上分析,笔者认为九江地区第四系中典型地裂缝发育是受区域性断裂和地震震中控制的,地裂缝的形成是区域性断裂活动和古地震事件在地表的响应。九江地区第四纪地裂缝的发现,给该区的断裂活动性和古地震研究提供了丰富的研究材料,也为断裂活动性和古地震研究提供了一个新研究思路和研究方法。 相似文献
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沂沭断裂带北段东支断裂的浅部构造特征及活动性 总被引：1，自引：0，他引：1
沂沭断裂带北段即潍坊市朱里以北的隐伏构造区,其主要隐伏活动断裂对第四系的发育具有控制作用。沂沭断裂带的活动性具有东强西弱的特点,其东支主干断裂是新构造运动强活动带,对地震的发生具有控制作用。莱州湾地区所开展的1∶5万区域地质调查、工程地质调查,通过大量的地面调查、物探、钻探等工作,对沂沭断裂带北段安丘-莒县断裂、昌邑-大店断裂的空间分布及活动性进行了深入调查研究,结果表明:两条主干断裂呈NNE向大致平行展布延伸,进入莱州湾海域,其中昌邑-大店断裂活动性质表现为走滑为主兼具逆冲运动,倾角近直立,倾向大致以东冢村北为界,由南段的倾向东转为北段的倾向西,该断裂最晚活动时代为晚更新世。安丘-莒县断裂控制了新生代地层的空间分布,新生代以来活动方式以向西正断为主,错断全新世地层并造成地表建筑物的开裂,目前仍处于活动期。本次调查首次确定了昌邑潜凸起的存在,该凸起位于断裂带北段东支两条主断裂之间,凸起区第四系厚度明显变薄,局部基岩出露;以柳疃断裂为界,北段潜凸区第四系下伏地层为新近纪明化镇组、馆陶组;南段潜凸区第四系下伏地层为新近纪八亩地组、牛山组,古近纪朱碧店组和白垩纪红土崖组。昌邑潜凸起区的发现对于莱州湾南岸水文地质、工程地质调查研究工作具有重要意义。 相似文献
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卢海峰 《大地构造与成矿学》2021,45(3):478-491
活动构造与地震地质方面研究揭示,中国南北地震带西南边缘的元谋断裂带晚第四纪活动特征总体表现为北强南弱,活动性质由北段(江边以北)全新世伸展性左行走滑、向南逐步过渡为全新世早中期的剪切性左行走滑、至南段(罗川以南段)晚更新世挤压式整体抬升和全新世活动不明显特征.综合地震地质灾害发育特点的调查结果表明,元谋断裂带北段震害特点表现为地表形变、新滑坡体产生和老滑坡体复活、崩塌及地裂缝发育、泥石流和砂土液化等.断裂带中段(江边-罗川段)控制的盆地边缘主要发育了大面积洪积扇体,在水流作用下易引起泥石流;此外,老滑坡体复活、局部崩塌、软土变形和砂脉等现象也较发育.南段(罗川以南段)灾害则以沿断层破碎带的塌方、老滑坡体复活、局部泥石流等为主.元谋断裂带的晚第四纪活动性质、地震灾害类型及分布特征表明,该断裂带晚第四纪活动性分段特征明显影响着构造带上及其附近的地震地质灾害类型、分布特征及未来地震活动趋势,断裂北段更易诱发中-强震,且该构造带晚更新世以来的伸展-剪切变形作用和地震活动均具有向南扩展的趋势.认识元谋断裂带晚第四纪变形特征与地震地质灾害发育特点对于深入探索青藏高原东南缘新构造期以来的构造变动、机理与引起的震害响应关系,以及进一步开展该区工程场地选址和地震地质灾害防治等工作意义重大. 相似文献
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怀远—池河断裂与郯庐断裂带南段相交,处在郯庐断裂带活动性逐渐减弱的地段。为获取断裂活动的地质证据,选取安徽韭山东北缘进行地貌调查、探槽开挖、年龄样品测试等工作。研究表明,韭山东北缘的线性地貌受断裂活动控制,在调查揭示的多个剖面中,断层表现出一致的活动性质,走向NW,倾向NE,倾角70°左右,具有正断性质;断层垂直断距在第四系中由下往上逐渐变小,直至消失在第四纪覆盖层中,说明断裂具有多期活动,进入中更新世后活动性逐渐减弱。通过跨断层探槽剖面分析及测年结果可知,断层最新活动错断了中更新世地层,上覆的中更新世顶部地层及晚更新世地层未受影响,说明该断裂是一条中更新世断裂,晚更新世以来不活动。怀远—池河断裂的活动情况与其所在地区的新构造环境有关。郯庐断裂带是本区规模最大的控制性构造,它的活动性对区内其他断裂具有重要影响,断裂带明光以南段最新活动时代为中更新世,受其影响,与它相交的怀远—池河断裂最新活动时代也表现为中更新世。这或是蚌埠—凤阳地区以中小地震活动为主的一个构造背景。 相似文献
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东濮凹陷北部沙三中亚段广泛发育盐岩和烃源岩,这两个看似不能共存的物质却在这里互层共生。该时期研究区沉积特征为多盐韵律与多层烃源岩互层共生、连续沉积,单个盐韵律厚度从几米到十几米,烃源岩有机质丰度高、类型好。平面上,两者在湖盆沉积沉降中心共生;垂向上,高有机质丰度、好干酪根类型与高盐度地层具有较好的对应关系。因而成为恢复古气候和古环境的重要研究对象。通过岩石学、古生物学以及Sr/Ba、B/Ga、(V+Ni+Mn)、Fe/Mn、Sr/Cu、Mg/Ca、V/(V+Ni)、稀土元素含量和氯同位素等方法对凹陷北部沙三中亚段的沉积环境进行研究。结果表明,凹陷北部沙三中亚段为深水沉积的还原环境,古盐度较高,达到半咸水-咸水沉积;微量元素和孢粉化石特征表明研究区沙三中亚段为温暖潮湿的环境。 相似文献
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The Importance of the Precipitation and the Susceptibility of the Slopes for the Triggering of Landslides Along the Roads 总被引：3，自引：1，他引：2
Clemente Irigaray Francisco Lamas Rachid El Hamdouni Tomás Fernández José Chacón 《Natural Hazards》2000,21(1):65-81
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning. 相似文献
13.
郯庐断裂南段研究进展与断裂性质讨论 总被引：13，自引：3，他引：13
据1：5万区域地质调查和专题研究资料，就郯庐断裂带是否南延与消失的原因，其与大别—苏鲁造山带交截形成的假位错效应，以及与中新生代沉积盆地形成演化的关系等作了新的阐述。在此基础上，讨论了郯庐断裂带是否为巨大的左行平移断层或转换断层。认为郯庐断裂带可能是在“古郯庐带”的基础上于早侏罗世重新活动、白垩纪强烈活动的地堑型枢纽断裂带。 相似文献
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Guboglo M. N. 《GeoJournal》1980,4(1):53-58
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen. 相似文献
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某高速公路下伏煤矿采空区稳定性分析 总被引：10，自引：0，他引：10
在论述某高速公路下伏砦脖煤矿采空区地质、采矿和工程地质特征的基础上, 进行了稳定性数值模拟分析, 定性与定量地分析与评价了该煤矿采空区的地表变形特征及稳定性。研究结果表明: 该煤矿采空区的变形尚未完成, 对拟建的高速公路将产生很大的危害, 必须采取相应的工程治理措施。 相似文献
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Jiayu Rong Michael Melchin S. Henry Williams Tatyana N. Koren Jacques Verniers 《《幕》》2008,31(3):315-318
The Global Stratotype Section and Point （GSSP） for the base of the Silurian System was defined in 1985. Since that time, a number of researchers have suggested that this section has serious deficiencies for use as a GSSP. As a result, in 2000, the Subcommission on Silurian Stratigraphy （SSS） proposed undertaking a formal restu@ of this GSSP, which was subsequently approved by the International Commission of Stratigraphy （ICS）. The result of this restudy was the formal proposal that the current GSSP, at 1.6 m above the base of the Birkhill Shale, at Dob＇s Linn, Scotland, should be maintained as the same locality and stratigraphic level, but the bios- tratigraphical definition of the boundary should be revised. The previously defined, basal Silurian grapto- lite zone, the Parakidograptus acuminatus Zone, should be subdivided into a lower Akidograptus ascensus Zone and a higher E acuminatus Zone. The base of the A. ascensus Zone, marked by the first appearance of A. ascensus, should be regarded as the biostratigraphic mark for the base of the Silurian. This proposal has now been formally approved by the SSS and ICS, and ratified by International Union of Geological Sciences. This is the first GSSP to undergo formal restudy and redefini- tion, and the proposal also included a recommended procedure for restudy of GSSPs. 相似文献
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Dean S. Oliver 《Mathematical Geology》1998,30(7):911-933
In reservoir characterization, the covariance is often used to describe the spatial correlation and variation in rock properties or the uncertainty in rock properties. The inverse of the covariance, on the other hand, is seldom discussed in geostatistics. In this paper, I show that the inverse is required for simulation and estimation of Gaussian random fields, and that it can be identified with the differential operator in regularized inverse theory. Unfortunately, because the covariance matrix for parameters in reservoir models can be extremely large, calculation of the inverse can be a problem. In this paper, I discuss four methods of calculating the inverse of the covariance, two of which are analytical, and two of which are purely numerical. By taking advantage of the assumed stationarity of the covariance, none of the methods require inversion of the full covariance matrix. 相似文献
19.
Deviation of the major axis of the inertia ellipsoid of the Moon from the direction toward the Earth
B. P. Kondratyev 《Astronomy Reports》2017,61(8):709-714
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″. 相似文献
20.
正Artemia cysts are an extremely important component of aquaculture diets.It is well established that the cultivation of fish and shellfish derive substantial health and growth advantages when Artemia are included in the diets of the 相似文献