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1.
准噶尔盆地油气资源丰富,位于准噶尔盆地与北天山结合部位的准噶尔盆地南缘,构造复杂,地震方法应用效果不理想,因此利用综合地球物理方法圈定研究区页岩气产出层位二叠系芦草沟组的分布深度与范围。通过200块岩石标本物性测量,获得了研究区主要地层密度、磁化率、极化率及电阻率等物性参数:研究区主要为沉积岩系,磁性普遍较弱,其中二叠系地层较三叠系地层磁性小;各地层密度差异不大,其中砂岩密度常见值2.61×10 3 kg/m 3 、泥岩密度常见值2.56×10 3 kg/m 3 、页岩密度常见值2.54×10 3 kg/m 3 ;各地层电性特征差异较大,电阻率特征呈现如下关系:砂岩>泥岩>页岩。对实测重力、磁法、大地电磁测深等地球物理数据进行处理及反演,得到了研究区布格重力异常平面等值线图、磁异常平面等值线图及大地电磁三维反演电阻率结构模型图。研究区东南部主要表现为高布格重力异常、负磁异常特征,布格重力异常峰值为9.5×10 -5 m/s 2 ,磁异常峰值为-100 nT;西北部主要表现为低布格重力异常、正磁异常特征,布格重力异常峰值为-12×10 -5 m/s 2 ,磁异常峰值280 nT。MT三维反演结果显示芦草沟组a、b段分别为较高阻和中低阻。芦草沟组总体表现为中低重力、中低电阻、低磁异常特征。结合地质资料,建立了重磁电综合解释地质剖面。根据断裂破碎带表现为低重力、低电阻、低磁异常特征,新推断出研究区8条逆断层,并进一步推断了研究区芦草沟组地层空间展布特征,为下一步勘探井位论证提供了地球物理依据。  相似文献   

2.
开展航空重力测量数据处理方法研究,提高数据处理的精度,赶超世界先进水平,具有十分重要的意义。本文基于国产三轴稳定平台式航空重力测量系统,开展了航空重力测量数据处理方法研究及相应的软件研制,实现了适用于稳定平台式航空重力数据的卡尔曼平滑算法,在国内首次解算出平台式航空重力空间异常,内符合精度达到0.590×10~(-5)m/s~2,外符合(与GT航空重力测量系统测量数据对比)精度达到0.581×10~(-5)m/s~2,数据处理精度达到国际先进水平。由此表明:数据处理采用的方法可行,解算精度高,提升了我国航空重力测量数据处理技术水平。  相似文献   

3.
王亮 《地质与勘探》2020,56(2):387-402
在黔湘桂一带,湖南黔阳-溆浦-城步的白马山-中华山-崇阳坪-瓦屋塘、五团-苗儿山-越城岭及广西融安-贵州从江的摩天岭、元宝山,地表出露花岗岩体上反映为重力低、磁力低的地球物理场响应特征。在贵州梵净山、九万大山出露的花岗岩体上也表现为重力低、磁力低及高电阻率的物理性质,与邻省极其相似。因此,本文根据中酸性岩浆岩的物性表征,以剩余重力值-2×10~(-5)m/s~2、磁场强度值-10 n T等量线为基础,外加布格重力异常负圈闭,圈定了贵州境内逾百处隐伏岩体分布,其推测成果对寻找与中酸性岩体有关的矿产具有指示作用。  相似文献   

4.
贵州地表除峨眉山玄武岩外,其他岩浆岩出露不多。为了解深部的基性-超基性岩体隐伏情况及分布形态,本文结合地表该类岩体反映的地球物理场响应特征,利用区域重磁资料综合研究。在镇远马坪(钾镁煌斑岩)、贞丰鲁容-阴河(钙碱性煌斑岩)、罗甸沟亭-望谟大观(辉绿岩)、晴隆-织金西北(玄武岩)等岩浆岩出露区,与重磁场同位置相对应地区表现为重力高、磁力高分布特征,且重磁异常强度表现为高低不一的幅值变化。为保证将最小的隐伏岩体圈定,尽量消除区内岩浆岩受区域性剥蚀、风化的影响,故利用重力值2×10~(-5)m/s~2、磁力值10 nT为基准,联合圈定了省内百余处基性-超基性岩体分布,对寻找有关联的矿产指明了勘查方向。  相似文献   

5.
北准噶尔增生杂岩带重磁场特征及构造解译   总被引:1,自引:0,他引:1  
通过系统统计新疆准噶尔北部地区主要岩矿石磁性、密度参数,重点研究了该区航空磁场、区域重力场分布规律。按照布格重力和航磁异常形态,准噶尔地区可以划分为三个布格重力异常单元和五个航磁异常单元,认为北准噶尔地区的布格重力异常和航磁异常揭示该区可能为一陆缘增生杂岩带。该增生杂岩带形态上呈"锲形",其北缘位于阿尔泰–富蕴断裂一带,西部与哈萨克斯坦板块毗邻,南部边缘为阿尔曼太蛇绿混杂岩带。该增生杂岩带由多个增生单元"拼贴"而成,具北东向凸起特点。阿尔泰–阿尔金地学断面揭示了增生杂岩带深部俯冲形态。本次研究成果为研究新疆北部与邻区大地构造提供了新的依据。  相似文献   

6.
林周县轮郎铅锌矿区位于拉萨-林周-墨竹工卡铅锌成矿区中部,属雅鲁藏布江巨型铜多金属成矿带北亚带。根据该区地球物理测量成果,共圈出重力异常区10个、磁力异常区18个。通过对重力异常特征及磁力异常特征综合评价,分析出其中5个磁力异常区和重力异常有明显的对应关系,属矿致异常,具良好的找矿前景;并且得出该区高磁区、局部磁异常与局部重力高的结合部和重、磁双高地带均为找矿潜力区。  相似文献   

7.
利用重磁水平和垂直二阶导数确定东北地区梯度带   总被引:1,自引:0,他引:1  
分析了东北地区的重、磁场特征,同时对研究区的布格重力异常和航磁异常数据进行水平和垂直求导。水平和垂直参量图能给出断裂和走向的信息。结合布格重力异常图可以得出东北地区重力梯度带的走向和边界,并对比重力和磁力的垂直和各个角度的水平二阶导数来综合确定东北地区梯度带。利用求重力和磁力的水平和垂直二阶导数来划分东北地区梯度带。  相似文献   

8.
鲁西金刚石原生矿床成矿背景复杂,由于缺乏地壳结构、岩浆侵入体位置、断裂规模等信息作为参考依据,深部构造特征及其在成矿过程中的作用尚不明确。本文基于重磁数据和地震剖面资料,采用Parker Oldenburg界面法、功率谱法和2. 5D重磁震联合反演等方法,获得了鲁西地区地壳结构、断裂规模、岩浆侵入体位置等信息,在此基础上,探讨了金刚石原生矿床的深部构造背景。结果表明:鲁西金刚石原生矿床分布于区域布格重力异常低值区、磁异常中 低值区,布格重力异常平均值低于-100×10-5m/s2,磁异常变化范围较大,介于-160~60 nT之间;矿床位于莫霍面、居里面等值线密集的梯度带,即稳定区域与活化区域的过渡带,莫霍面深度约为31. 2~32. 2 km,居里面深度约27. 5~30 km;矿床分布区NW向断裂构造切割深度均超过20 km,其中蒙山断裂切割深度为35 km,深达上地幔,新泰 垛庄断裂切割深度为28. 5 km,深达居里面,泰山 铜冶店断裂切割深度为20. 5 km;金伯利岩于古生代形成后,受中生代伸展构造影响,被NW向断裂逐级抬升、剥蚀,直至出露地表。金刚石品位自南向北逐渐降低是由于北部抬升幅度大,剥蚀接近金伯利岩根部的结果,指示南部矿带找矿潜力大。  相似文献   

9.
大连周边海域航空重力调查方法及重要成果   总被引:4,自引:4,他引:0       下载免费PDF全文
为加强海洋地质调查工作,中国地质调查局组织实施了海洋航空地球物理探测及应用项目,在大连海域及其周边,应用GT-1A航空重力测量系统,开展了1∶20万航空重力调查工作,获取了高质量的航空重力数据9.4万测线km,原始测量总精度达到1.27×10~(-5)m/s~2;形成了一套覆盖渤海东部、北黄海、辽东半岛和山东半岛的航空重力系列图件,填补了研究区内航空重力资料的空白。通过综合解释与研究,在基底构造形态分析、主要构造单元边界厘定、断裂构造分布特征研究以及局部构造异常圈定等方面取得了重要成果,为研究区海洋区域地质调查、渤海和北黄海的油气资源调查、海陆过渡区关键地质问题的解决提供了重要依据。  相似文献   

10.
南海西北部重磁场及深部构造特征   总被引:9,自引:3,他引:9  
通过对南海重磁数据的重新处理,得到南海西北部自由空间重力异常图、布格重力异常图、磁异常图和化极磁异常图,并对所反映的地球物理场特征加以分析。根据重力场资料对研究区的地壳结构进行了反演计算,结果表明地壳厚度在10~38km之间,总的趋势由陆向洋逐渐减薄,对应于地壳类型从陆壳、过渡壳到洋壳的分布特征。根据磁力资料计算了居里面深度,其埋深变化于11~27km之间,在陆区居里面是下地壳顶界面和莫霍面之间的另一个物性界面,而在海区则接近于莫霍面埋深。  相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

13.
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003).  相似文献   

14.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

15.
China, as many other parts of the world, has a serious shortage of water resources. In China, there is a total amount of 2.8×10^12 m3 of freshwater, but that is only 2000 m3 per capita, which is about one quarter of the world average. Thereforc, seawater desalination engineering is of great significance to the nation.  相似文献   

16.
正Dear Authors and Readers:First of all,on behalf of the new Editorial Board,I would like to express our sincere appreciation for your continuing support of our journal.This journal,founded in 1922,is the oldest geological journal in China.As the flagship journal of the  相似文献   

17.
正The Wulashan-Hademengou gold ore district in Baotou city,Inner Mongolia,is a further newly discovered super-large gold metallogenic belt in northern China.The accumulated proven gold metal amount is 84.46 t,with an average grade of3.53 g/t and a gold metal amount of 63.16 t,with an average grade of 3.30 g/t.The potential reserves are over 100 t.  相似文献   

18.
正Since the first discovery of the excellent performance of nickel-bearing iron alloys in 1889,scientists have developed3000 more kinds of nickel alloys,which still have an enormous market demand at present.However,the scarcity of global nickel ore resources has restricted economic development.In recent years,experts from the Institute of Multipurpose Utilization of Mineral Resources have studied the comprehensive utilization technique of low-grade nickel ores from  相似文献   

19.
正Professor Shu received his undergraduate training in Paleontology at Peking(Beijing)University in1964–1969,obtaining his Master's degree at Northwest University(Xi’an)and Ph.D.in China University of Geosciences(Beijing);he was Visiting Scholar at the Smithsonian Institution,Washington,D.C.,USA in 1988,Humboldt Research Fellow at University of Bonn in 1988–1989,at University of Wuerzburg,Germany in 1994–1995,and Visiting Scholar at Cambridge University,UK  相似文献   

20.
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