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1.
东天山三岔口铜矿区矿化岩体SHRIMP U-Pb年代学及锶同位素地球化学特征研究 总被引：10，自引：1，他引：10
锆石SHRIMPU Pb年代学及全岩和含矿石英脉锶同位素组成研究表明 ,东天山三岔口铜矿区矿化斜长花岗斑岩的岩浆侵位年龄为 2 78± 4Ma(95 %可信度 ) ,即成岩成矿时代为早中二叠世 ;矿化斜长花岗斑岩、英云闪长 (玢 )岩及含矿石英脉的 (87Sr/ 86Sr) i 在测定误差内一致 ,介于 0 .70 370～ 0 .70 4 37之间 ,而计算得到的εSr(t)值变化于 - 8.5～ +2 .7之间。锶同位素组成特征表明 ,成矿岩体为典型的I型花岗岩 ,可能是幔源火山岩或上地幔物质部分熔融的产物。 相似文献
2.
安徽沙溪斑岩铜(金)矿床地质地球化学特征及成因 总被引：1，自引：1，他引：0
沙溪斑岩铜(金)矿床位于大别隆起北部金寨—舒城火山岩带的东南缘,庐江—枞阳中生代火山岩盆地的西北缘,处于郯庐断裂带内部,是中国东部与闪长岩类有关斑岩铜(金)矿床的典型实例。其成矿岩体——石英闪长斑岩的Rb-Sr同位素等时线年龄为127.9±1.6Ma,富碱、富钠、富轻稀土和大离子亲石元素,并具较低的锶同位素初始比值(I_(Sr)=0.70580,为壳幔混源岩浆演化分异的产物。矿床的蚀变和矿化分带模式与闪长岩模式相似。成矿流体具较高的含盐度,CO_2、Ca~(2+)、Na和Cl-组分高。主成矿期包裹体均一温度变化于280～420℃,成矿流体的δ~(18)O值变化于3.51‰～5.52‰,δD值介于82.4‰～-59.8‰,硫化物的δ~(34)S值变化于-0.3‰～2.49‰,包裹体中CO_2的δ~(13)C值介于-2.66‰～-6.53‰,同位素资料显示沙溪斑岩铜(金)矿床成矿热液及成矿物质主要来自岩浆体系。 相似文献
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4.
皖东侵入岩矿物Rb-Sr和Ar-Ar年代学及其与氧同位素平衡之间的关系 总被引：11，自引：0，他引：11
为探讨花岗质岩石中矿物O同位素平衡与Rb Sr矿物等时线年龄有效性之间的关系 ,测定了皖东屯仓与横山两个石英二长岩体中单矿物的Rb Sr和O同位素组成以及角闪石和黑云母的Ar Ar年龄。屯仓岩体的石英 -角闪石对温度为 5 4 5± 2 5℃ ,石英 -黑云母对温度为 4 6 0± 2 0℃ ,石英 -斜长石对温度 385± 4 0℃。横山岩体的石英 -角闪石对温度为 5 30± 2 5℃ ,石英 -黑云母对温度为 390± 15℃和石英 -斜长石对温度 2 85± 35℃。反映封闭体系中矿物在冷却过程中的退化交换再平衡。矿物间的氧同位素平衡对应于有地质意义的Rb Sr矿物等时线年龄。屯仓岩体的全岩 -角闪石 -斜长石Rb Sr等时线年龄 (12 8.4± 4 .7Ma)与角闪石的Ar Ar年龄 (12 5 .5 1± 0 .5 5Ma)在误差范围内一致 ,全岩 -角闪石 -斜长石 -黑云母Rb Sr等时线年龄 (12 0 .3± 2 .6Ma)与黑云母的Ar Ar年龄 (118.0± 0 .1Ma)一致。横山岩体的全岩 -角闪石 -斜长石Rb Sr矿物等时线年龄 (10 8± 15Ma)比角闪石的Ar Ar年龄 (12 5 .7± 1.8Ma)低 ,全岩 -角闪石 -斜长石 -黑云母Rb Sr等时线年龄 (118.6± 1.2Ma)小于黑云母的Ar Ar年龄 (12 0 .0± 0 .2Ma)。Rb Sr等时线年龄小于Ar Ar年龄是由于长石的蚀变引起的。大的等时线误差是由于Rb/Sr比值变化范围太小 相似文献
5.
采用Rb Sr全岩与粘土矿物等时线年龄方法测得山西五台剖面 (RS0 1) ,临县剖面 (RS0 2 )和孝义剖面 (RS0 3)的 3个含矿粘土岩的Rb Sr同位素年龄分别为 :316 .9± 1.2Ma ,87Sr/86Sr为 0 .710 5 4± 14 ;315 .5± 1.3Ma ,87Sr/86Sr为 0 .710 86±18;317.3± 1.1Ma ,87Sr/86Sr为 0 .710 5 0± 14。它们代表了铝土矿和含矿系列成矿的同位素年龄 ,相当于晚石炭世早期 相似文献
6.
高峰100号矿体硫、铅同位素特征 总被引：1，自引：0，他引：1
李蘅 《矿物岩石地球化学通报》2001,20(4):334-336
10 0号矿体的成矿物理化学环境为 :成矿温度 30 0± 30℃ ;成矿压力为 84.2× 10 5Pa ;LogfO2 =- 30 .4～- 35 .6 ,LogfCO2 =- 2 .5 5～ +0 .36 ,LogfS2 =- 8.3～ - 11.0 ,pH =4.2～ 4.9。同位素的分析结果 :硫化物的硫同位素为 6 4‰～ 12 .3‰ ,δ3 4 SΣS 值为 6 6～ 13 8;2 0 6Pb 2 0 4Pb值为 17 4 91～ 18 96 0 ,2 0 7Pb 2 0 4Pb值为 15 5 39～15 940 ,2 0 8Pb 2 0 4Pb值为 37 95 7～ 39 4 90。表明 10 0号矿体的硫源是混合硫 ,铅源是两种异常铅混合的结果。 相似文献
7.
北祁连山与斑岩有关的碲金型金矿床地质特征和成因模型 总被引：2，自引：1，他引：2
车路沟金矿床是北祁连山发现的首例与斑岩有关的碲 -铋 -金型矿床。金矿床成矿地质特征显示 ,矿床形成于岛弧火山期后次火山 -深成中酸性侵入岩体中 ,直接赋存于浅成 -超浅成英安斑岩内 ,其成矿背景为碰撞造山环境。矿床受区域断裂裂隙、同建造期古火山穹隆边缘继承性断裂裂隙 ,尤其受次火山岩体边缘节理、裂隙及接触破碎带控制。同位素研究资料显示 ,成矿流体 δ18OH2 O为 - 6 .5 8‰～ - 2 .30‰ ,δD为 - 5 8.2‰～ - 4 1.8‰ ,δ3 4S为 - 3.84‰～ + 3.2 0‰ ,δ13 CPDB为 - 8.5 4‰～ - 1.32‰ ,盐度为9.37‰～ 11.83‰ [w (Na Cl) eq],密度为 0 .982～ 1.0 0 6 g/ cm3 ,均一温度为 137.6～199.4℃。成矿流体总特征为低温、低气相、中 -高密度、并含有较高 CO2 的 H2 O- CO2 -Na Cl (KCl)体系。厘定了成岩年龄为 4 2 7.7± 4 .5 Ma,成矿年龄在 35 0～ 4 10 Ma。矿床是在岩体固结定位后 ,由深部岩浆房 (源 )分异出的富含 Au、Te、Cu等成矿元素 ,CO2 、SO2 、H2 O等挥发组分的岩浆热液沿控岩构造裂隙带上升 ,不断从沿途已固结的英安斑岩及围岩中萃取成矿物质 ,并与大量大气降水混合作用的产物。矿床成因类型属与斑岩有关的低温热液型碲金矿。 相似文献
8.
湖南柿竹园钨锡多金属矿床同位素地球化学研究 总被引：3，自引：0，他引：3
柿竹园钨锡多金属矿床中细粒和中粒黑云母花岗岩Rb-Sr等时线年龄分别为(133±23)Ma和(143±7.3)Ma;初始锶同位素比值分别为0.71774±0.01472和0.73297±0.03454.从花岗岩侵入到成矿作用晚期阶段,δ18OH2o和δDH2O分别从+5.6‰～+11.4‰和-56.0‰～-62.3‰变化到-5.8‰～-8.5‰和-48.0‰～-69.7‰.花岗岩中石英的δ18O值较高,为8.4‰～12.1‰,岩浆水的δ18O为5.6‰～11.4‰,δD为-56.0‰～-62.3‰,但钾长石、黑云母的δ18O值较低,计算出的氧同位素平衡温度低于花岗岩结晶温度,表明花岗岩形成后受到岩浆水和雨水的交换作用和蚀变作用.本矿床流体的氢氧同位素,具有独特的演化规律,用沸腾去气作用和雨水混合作用可以解释其流体氢氧同位素的组成特征. 相似文献
9.
内蒙古锡林格勒杂岩的地球化学研究:从Rodinia聚合到古亚洲洋闭合后碰撞造山的历史记录 总被引：23，自引：0，他引：23
内蒙古东部出露的锡林格勒杂岩主要由中元古代原岩为火成岩的黑云母片麻岩和斜长角闪岩透镜体组成。片麻岩显示轻稀土元素富集的中等分异特征 ,具明显的Eu负异常 ,其不相容元素特征与平均地壳类似但相对亏损Ba和Sr。斜长角闪岩构成一条Sm -Nd等时线 ,其年龄值为12 0 2± 6 5Ma ,εNd(1.2 0Ga)值为 6 .8。角闪岩的亏损地幔模式年龄 (tDM,1.2 6～ 1.32Ga)与其Sm -Nd同位素等时线年龄接近。角闪岩的Rb -Sr同位素等时线年龄为 393± 14Ma ,其87Sr/ 86 Sr初始比值为 0 .70 379± 0 .0 0 0 0 7,此Rb -Sr等时线年龄与本区出露的篮片岩Ar-Ar年龄 (～ 383Ma)一致 ,记录了中亚造山带东南部洋壳俯冲结束后由大陆碰撞造山引起的变质作用事件。黑云母片麻岩的Rb -Sr同位素等时线年龄为 2 79.5± 6 .4Ma ,87Sr/ 86 Sr初始比值为 0 .70 85 1± 0 .0 0 0 10 ,此Rb -Sr等时线年龄与本区广泛分布的早二叠世火山岩的Rb -Sr等时线年龄 (～ 2 77± 15Ma)一致 ,因此可能是由大规模岩浆活动诱发的变质作用的记录。锡林格勒杂岩因此不仅记录了Rodinia超大陆聚合的地质事件 ,并且通过对比研究本地区蛇绿岩和晚古生代岩浆岩的演化历史 ,可以恢复从Ro dinia超大陆聚合 (～ 1.2 0Ga)到古亚洲洋关闭 (～ 4 30Ma)、大陆碰撞造山 (～ 39 相似文献
10.
通过离子探针、K_Ar法和Re_Os法测得冈底斯斑岩铜矿带的成矿年龄。冈底斯斑岩铜矿带中驱龙石英二长花岗斑岩的SHRIMP年龄为 (17.5 8± 0 .74 )Ma ,冲江二长花岗斑岩的SHRIMP年龄为 (15 .6 0± 0 .5 2 )Ma,冲江闪长玢岩的SHRIMP年龄为 (14 .5 4± 0 .6 5 )Ma。驱龙和冲江含矿斑岩钾长石的K_Ar年龄分别为 (16 .4 3± 0 .31)Ma和 (15 .77± 0 .4 5 )Ma ,矿石中辉钼矿的Re_Os年龄分别为 (15 .99± 0 .32 )Ma和 (14 .85± 0 .6 9)Ma。因此驱龙和冲江斑岩铜矿的成矿年龄约束于 (17.5 8± 0 .74 )Ma～ (14 .85± 0 .6 9)Ma之间。驱龙石英二长花岗斑岩为强矿化岩石 ,冲江二长花岗岩斑岩为中等矿化岩石 ,冲江闪长玢岩为未矿化岩石 ,三者的年龄依次变小 ,放射性元素2 0 6Pb、U和Th含量则依次增高。这表明随着壳源物质混合的增强 ,铜矿化渐弱。立足于大西洋底栖有孔虫氧同位素变化和印度洋北部海底沉积扇的沉积速率变化来看青藏高原隆升 ,认为玉龙矿带和冈底斯矿带斑岩铜矿是在青藏高原两次最明显的地壳运动中形成的 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
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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