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1.
试经奥陶纪豹皮灰岩的古岩溶成因 总被引：1，自引：0，他引：1
本文通过对安微北部两个奥陶系面豹皮灰岩的宏观,微观及地球化学特征研究,认为豹皮灰岩的 成与奥陶纪灰岩沉积过程中的古岩溶作用及其后生改造密切相关。 相似文献
2.
《地学前缘》2007,14(6):215-221
通过野外实地考察测试,对水下收缩裂隙整体形成过程、裂隙内充填物沉积模式、影响因素等进行了详细讨论,并且建立了相应的地质理论模型。水下收缩裂隙的形成共分4个阶段,依次为:泥水混合物进入低洼地带的初始混浊状态;沉积压实稳定阶段;水位线下降,盐度增大,裂隙形成阶段;沉积裂隙充填阶段。其中“异常高压作用”,对于初始裂隙的形成、沉积物孔隙水的有效排出以及主要渗流通道的发育起到了重要作用。单一泥质地层裂隙内充填物沉积模式与沙泥互层的多旋回地层略有差异,主要表现为沙层的润滑作用以及对早期裂隙内充填物类型的影响。上述两种地层裂隙内充填物沉积特征均与后期充注期次相对应,表现出很好的韵律性。裂隙纵剖面中生物发育层的出现,对裂隙内充填物的物理、化学性质将产生重要影响。 相似文献
3.
<正> 形成岩溶的可溶岩,前人有深入研究和确切分类。对岩溶作用过程中的洞穴化学沉积—堆积物、洞穴矿物也有研究和系统分类,但对其余形成物则研究不够或归类不当。我国广大岩溶区内,普遍存在一种以碳酸盐岩的角砾、岩(晶)屑为颗粒,由钙泥质充填胶结的岩石系列,以往称之为角砾状灰岩、底砾岩、膏溶角砾岩、构造岩等。从成因上看,这类岩石多数与岩溶作用有关。确切地说,这是一套混杂的岩石组合,可分为断裂作用、岩溶交代改造作用、岩溶作用形成的岩石类型。后者纯属岩溶沉积—堆积建造,其岩石特征、成岩环境、成矿特征都较特殊,它取决于岩溶发育期内的岩溶地貌、水文、地质、气候等条件。近来,在这方面,刘立钧等同志对湘中、湘南地区的岩溶角砾岩产状和岩溶作用旋回进行了有意义的探索。 相似文献
4.
通过野外实地考察测试,对水下收缩裂隙整体形成过程、裂隙内充填物沉积模式、影响因素等进行了详细讨论,并且建立了相应的地质理论模型。水下收缩裂隙的形成共分4个阶段,依次为:泥水混合物进入低洼地带的初始混浊状态;沉积压实稳定阶段;水位线下降,盐度增大,裂隙形成阶段;沉积裂隙充填阶段。其中“异常高压作用”,对于初始裂隙的形成、沉积物孔隙水的有效排出以及主要渗流通道的发育起到了重要作用。单一泥质地层裂隙内充填物沉积模式与沙泥互层的多旋回地层略有差异,主要表现为沙层的润滑作用以及对早期裂隙内充填物类型的影响。上述两种地层裂隙内充填物沉积特征均与后期充注期次相对应,表现出很好的韵律性。裂隙纵剖面中生物发育层的出现,对裂隙内充填物的物理、化学性质将产生重要影响。 相似文献
5.
北京周口店豹皮灰岩的变形特征 总被引：1，自引：0，他引：1
周口店地区广泛分布的寒武纪地层府君山组底部灰岩因其具典型的豹斑状构造而被称为豹皮灰岩。本文主要以出露于周口店黄院地区的豹皮灰岩为研究对象。组成豹皮灰岩的物质成分有2种,一为白云质成分的豹斑,其余部分为泥灰质。在露头尺度上,豹皮灰岩中的豹斑发生了明显的旋转变形并具有一定的定向性,而泥灰质成分则具有清晰的韧性变形特征,为较典型的碳酸盐糜棱岩;在微观尺度上,构成豹斑的白云石矿物未发生韧性变形,而泥灰质成分中的方解石具有明显的细粒化、拉长和定向。豹皮灰岩变形发生时岩石所处的温度介于200～250℃之间。豹皮灰岩的形成经历了原岩形成和后期构造变形改造2个阶段,于寒武纪由沉积作用形成了岩石的物质组分和原生层状构造,在前印支期受水平剪切作用形成岩石的豹斑状构造。 相似文献
6.
塔河油田奥陶系碳酸盐岩储层特征几点新认识 总被引：6，自引：1，他引：6
塔河油田奥陶系发育有洞穴型、风化裂隙型、构造裂隙型、裂隙—孔洞型、溶蚀孔隙型五类性质有别的储层。其中洞穴型储层发育具有普遍性,纵向上往往表现为两个洞穴型储层带的发育,两个洞穴型储层的形成与两个岩溶旋回的潜流溶蚀带相对应;有效洞穴型储层发育是油气高产、稳产的关键。风化裂隙型储层主要集中在海西早期不整合侵蚀面附近及洞穴层上下,其储层的孔隙度和渗透率相对较高,可具有较高的油气产能。区内发育五期构造裂隙,其中第Ⅳ期部分充填裂隙和第Ⅴ期未充填裂隙具有储集意义。 相似文献
7.
方解石充填物对于深层古岩溶洞穴保存的独特意义--以塔河地区奥陶系为例 总被引：2，自引：1，他引：1
塔河油田奥陶系古岩溶洞穴埋藏深度之大在世界范围内罕见,但对其为何没有垮塌殆尽的原因却知之甚少。为了探究其保存机制,对比了Fort Worth盆地奥陶系深埋洞穴,发现大量缝、洞充填方解石是塔河地区洞穴中常见且特有的充填物。在统计和综合分析缝洞方解石充填物地球化学数据的基础上,以洞穴充填方解石成因类型为切入点,详细分析了构造运动背景、热液活动、油气充注、方解石的产状以及洞穴受力情况,通过与Fort Worth盆地深埋洞穴埋藏史的对比和分析,提出塔河地区深埋岩溶洞穴的一种保存机制。研究区岩溶洞穴方解石主要是长期浅埋阶段,以大气淡水成因为主,海水成因为辅形成,深埋过程还受到了溶蚀性流体（岩浆热液和有机酸）后期改造。方解石充填物增加了洞穴的抗压性,岩溶洞穴内部充填的方解石在埋藏过程中支撑了洞穴;岩溶洞穴顶部裂纹中充填的方解石还“愈合”了洞穴周边的裂纹,强化了洞穴的顶板,增加了洞穴整体的稳定性。充填的方解石在垮塌前占据了部分洞穴空间,在埋藏后,高温有机酸、CO2、H2S和岩浆热液沿着深大断裂等通道对奥陶系碳酸盐岩改造溶蚀作用明显,也对处于优势通道和良好储集性能的洞穴充填方解石进行了改造,恢复了部分洞穴空间。因而认为地表、近地表方解石充填过程是碳酸盐岩洞穴型储层的“保持性成岩作用”。 相似文献
8.
塔里木盆地早海西期多期次风化壳岩溶洞穴层 总被引：25，自引：5，他引：20
洞穴层是识别多期次岩溶旋回的标志,是岩溶旋回连接沉积旋回及周期性海平面变化的纽带。本文通过古地貌恢复,将从钻井剖面中识别的洞穴层归位到早石炭世古地貌剖面中,根据洞穴层总是沿稳定古潜水面发育的特点划分对比洞穴层。通过洞穴层的形成条件、充填结构分析,推断洞穴层发育序次、洞穴层与其同时期形成的沉积地层的时空对应关系,并据此对洞穴层进行盆地范围内跨地区对比、总结斜坡及岛屿两种不同的洞穴层发育模式。研究结果表明,在早海西期,塔北、塔中、和田古隆起中、下奥陶统碳酸盐岩陆块内部发育了3个期次的风化壳岩溶洞穴层,其序次为下老上新,它们是在早石炭世间歇性海平面上升过程中形成的,其同时期形成的沉积地层分别为下石炭统东河砂岩段、生屑灰岩段、下泥岩段中上部。洞穴层内部多旋回“坍塌角砾-地下河沉积”组合是斜坡内陆区潜流面的迟后上升效应,洞穴层与洞穴等时层的时空对应关系对于大型古岩溶事件的断年及洞穴层的分布预测具有重要意义。 相似文献
9.
马家沟灰岩（古）岩溶研究中的若干问题探讨 总被引：4，自引：0，他引：4
讨论了华北地区奥陶系马家沟组灰岩岩溶研究中的几个问题，包括沉积岩溶，暴露岩溶，埋藏岩溶，现代岩溶及陷落柱等，指出了沉积岩溶和暴露岩溶洞穴不能保存或保存甚少，但对后期的岩溶发育具有重要控制作用，最后，提出了今后奥陶系灰岩岩溶研究的基本思路。 相似文献
10.
苏州高岭土矿包括阳东、阳西、观山三个矿区。东矿区矿体呈透镜状产于古岩溶洞穴和逆掩断层带中;西矿区矿体呈似层状、透镜状产于逆掩断层带中;观山矿区矿体呈大的似层状产于灰岩剥蚀面上。根据控矿因素分析,矿床成因属构造岩型高岭土及古岩溶洞穴充填物蚀变型高岭土。构造岩型高岭土矿为一种新类型。 相似文献
11.
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
12.
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
14.
15.
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
16.
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
17.
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
18.
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