海上油气化探技术及应用   总被引：4，自引：2，他引：4  

吴传芝  程同锦  宣玲 《物探与化探》2004,28(5):377-381,393

海域油气化探测量指标一般为海底沉积物中的烃类及其蚀变产物和海水介质中的烃类,以烃类浓度及其蚀变产物为主要测量对象的油气化探是评价海上油气远景为数不多的重要方法之一。目前底层水采样分析与海底沉积物取芯分析已成为海上油气化探一种有效且相对经济的技术组合,海底沉积物取芯测量和海水嗅探器现场分析是海上油气化探的主要手段。国内外众多海域油气化探研究结果证实,海域油气化探在含油气远景区块识别和含油气远景构造油气属性判识方面可以提供重要的地球化学信息。  相似文献   

Inclusions in diamonds from the K14 and K10 kimberlites, Buffalo Hills, Alberta, Canada: diamond growth in a plume?     

Rondi M. Davies  William L. Griffin  Suzanne Y. O''Reilly  Tom E. McCandless 《Lithos》2004,77(1-4):99-111

Analyses of mineral inclusions, carbon isotopes, nitrogen contents and nitrogen aggregation states in 29 diamonds from two Buffalo Hills kimberlites in northern Alberta, Canada were conducted. From 25 inclusion bearing diamonds, the following paragenetic abundances were found: peridotitic (48%), eclogitic (32%), eclogitic/websteritic (8%), websteritic (4%), ultradeep? (4%) and unknown (4%). Diamonds containing mineral inclusions of ferropericlase, and mixed eclogitic-asthenospheric-websteritic and eclogitic-websteritic mineral associations suggests the possibility of diamond growth over a range of depths and in a variety of mantle environments (lithosphere, asthenosphere and possibly lower mantle).

Eclogitic diamonds have a broad range of C-isotopic composition (δ¹³C=−21‰ to −5‰). Peridotitic, websteritic and ultradeep diamonds have typical mantle C-isotope values (δ¹³C=−4.9‰ av.), except for two ¹³C-depleted peridotitic (δ¹³C=−11.8‰, −14.6‰) and one ¹³C-depleted websteritic diamond (δ¹³C=−11.9‰). Infrared spectra from 29 diamonds identified two diamond groups: 75% are nitrogen-free (Type II) or have fully aggregated nitrogen defects (Type IaB) with platelet degradation and low to moderate nitrogen contents (av. 330 ppm-N); 25% have lower nitrogen aggregation states and higher nitrogen contents (30% IaB; <1600 ppm-N).

The combined evidence suggests two generations of diamond growth. Type II and Type IaB diamonds with ultradeep, peridotitic, eclogitic and websteritic inclusions crystallised from eclogitic and peridotitic rocks while moving in a dynamic environment from the asthenosphere and possibly the lower mantle to the base of the lithosphere. Mechanisms for diamond movement through the mantle could be by mantle convection, or an ascending plume. The interaction of partial melts with eclogitic and peridotitic lithologies may have produced the intermediate websteritic inclusion compositions, and can explain diamonds of mixed parageneses, and the overlap in C-isotope values between parageneses. Strong deformation and extremely high nitrogen aggregation states in some diamonds may indicate high mantle storage temperatures and strain in the diamond growth environment. A second diamond group, with Type IaA–IaB nitrogen aggregation and peridotitic inclusions, crystallised at the base of the cratonic lithosphere. All diamonds were subsequently sampled by kimberlites and transported to the Earth's surface.  相似文献   

Mineral inclusions and geochemical characteristics of microdiamonds from the DO27, A154, A21, A418, DO18, DD17 and Ranch Lake kimberlites at Lac de Gras, Slave Craton, Canada   总被引：1，自引：0，他引：1  

Rondi M. Davies  William L. Griffin  Suzanne Y. O''Reilly  Buddy J. Doyle 《Lithos》2004,77(1-4):39-55

A mineral inclusion, carbon isotope, nitrogen content, nitrogen aggregation state and morphological study of 576 microdiamonds from the DO27, A154, A21, A418, DO18, DD17 and Ranch Lake kimberlites at Lac de Gras, Slave Craton, was conducted. Mineral inclusion data show the diamonds are largely eclogitic (64%), followed by peridotitic (25%) and ultradeep (11%). The paragenetic abundances are similar to macrodiamonds from the DO27 kimberlite (Davies, R.M., Griffin, W.L., O'Reilly, S.Y., 1999. Diamonds from the deep: pipe DO27, Slave craton, Canada. In: Gurney, J.J., Gurney, J.L., Pascoe, M.D., Richardson, S.H. (Eds.), The J. B. Dawson Vol., Proc. 7th Internat. Kimberlite Conf., Red Roof Designs, Cape Town, pp. 148–155) but differ to diamonds from nearby kimberlites at Ekati (e.g., Lithos (2004); Tappert, R., Stachel, T., Harris, J.W., Brey, G.P., 2004. Mineral Inclusions in Diamonds from the Panda Kimberlite, S. P., Canada. 8th International Kimberlite Conference, extended abstracts) and Snap Lake to the south (Dokl. Earth Sci. 380 (7) (2001) 806), that are dominated by peridotitic stones.

Eclogitic diamonds with variable inclusion compositions and temperatures of formation (1040–1300 °C) crystallised at variable lithospheric depths sometimes in changing chemical environments. A large range to very ¹³C-depleted C-isotope compositions (δ¹³C=−35.8‰ to −2.2‰) and an NMORB bulk composition, calculated from trace elements in garnet and clinopyroxene inclusions, are consistent with an origin from subducted oceanic crust and sediments. Carbon isotopes in the peridotitic diamonds have mantle compositions (δ¹³C mode −4.0‰). Mineral inclusion compositions are largely harzburgitic. Variable temperatures of formation (garnet T_Ni=800–1300 °C) suggest the peridotitic diamonds originate from the shallow ultra-depleted and deeper less depleted layers of the central Slave lithosphere. Carbon isotopes (δ¹³C av.=−5.1‰) and mineral inclusions in the ultradeep diamonds suggest they formed in peridotitic mantle (670 km). The diamonds may have been entrained in a plume and subcreted to the base of the central Slave lithosphere.

Poorly aggregated nitrogen (IaA without platelets) in a large number of eclogitic (67%) and peridotitic (32%) diamonds, with similar nitrogen contents, indicates the diamonds were stored in the mantle at low temperatures (1060–<1100 °C) following crystallisation in the Archean. Type IaA diamonds have largely cubo-octahedral growth forms, and Type II and Type IaAB diamonds, with higher nitrogen aggregation states, mostly have octahedral morphologies. However, no correlation between these groups and their mineral inclusion compositions, C-isotopes, and N-contents rules out the possibility of unique source origins and suggests eclogitic and peridotitic diamonds experienced variable mantle thermal states. Variation in mineral inclusion chemistries in single diamonds, possible overgrowths of ¹³C-depleted eclogitic diamond on diamonds with peridotitic and ultradeep inclusions, and Type I ultradeep diamond with low N-aggregation is consistent with diamond growth over time in changing chemical environments.  相似文献   

Découverte d'un diatrème de kimberlite diamantifère à Séguéla en Côte-d'Ivoire     

André Pouclet  Marc Allialy  Bertin Daouda-Yao  Botty Esso 《Comptes Rendus Geoscience》2004,336(1):9-17

The Séguéla area in Ivory Coast is known for its diamond-bearing field related to dykes of kimberlite and lamproite. These dykes, devoid of any deformation and metamorphism, crosscut the Birimian formations. Their N 170° orientation is controlled by the tectonized contact between the Archean and the Paleoproterozoic shields of the West-African craton. Discovery of a diatreme, with its pipe breccias and well-preserved maar sediments, below the present-day colluvia, attests for the probable recent geological age (Cretaceous?) of the kimberlitic activity. To cite this article: A. Pouclet et al., C. R. Geoscience 336 (2004).  相似文献   

TGQ系列勘察取样钻机(具)的研究          下载免费PDF全文

朱文鉴  张培丰  张建元 《探矿工程》2004,31(2):33-36

取样钻技术是区域地质填图、物化探取样、古地磁取样、地质灾害预警防治和工程勘察等必不可少的技术手段。TGQ系列勘察取样钻机包括TGQ-1、5、10三个型号，分析了其结构、特性和特点，以及配套钻具和取样器。  相似文献   

时空多点连续定向取心技术应用研究          下载免费PDF全文

周策  陈文俊 《探矿工程》2004,31(8):36-38

为解决以往定向仪不抗振、岩样采取率不高等问题，利用时间与钻孔空间位置对应的关系，研制成功了KD型定向仪。详细介绍了该定向仪的基本构成、技术参数及现场应用情况。  相似文献   

合理设计岩屑规程保证正常钻进条件——金刚石钻进技术专题之一          下载免费PDF全文

汤凤林  段隆臣  В.Ф.Чихоткин  刘晓阳 《探矿工程》2004,31(6):45-48

论述了正常钻进的条件，提出了合理岩屑规程是保证正常钻进的关键和设计钻头的主要依据之一，讨论了岩屑规程与金刚石钻头唇面工作状态、孔底表面粗糙度和岩屑粒度的关系，提出了相应的建议。  相似文献   

桩基筒形翼状钻头的改进设计及应用     

杨建林  兰凯  段隆臣  张涛  徐辉雄 《地质科技情报》2005,24(Z1):19-22

针对浙江省温州市世贸中心大厦桩基施工中硬岩钻进时出现的堵管、卡钻和效率低等问题,从所钻地层和钻头的磨损分析出发,提出了钻头的改进设计方案.改进型筒形翼状钻头比原先使用的平底滚刀钻头增加了18个孕镶金刚石-针状硬质合金复合式钻齿和3个钎头,并按受力特点进行了合理分布.实际钻进效果表明改进型钻头应用于超深、大直径钻孔的钻进效率较高、钻进过程平稳.针对钻头的实际磨损情况提出了钻头进一步改进设计的建议.  相似文献   

HXY-800QT型拖车钻机的研制及应用          下载免费PDF全文

胡仲杰  张联库  邓小军  刘彦仁 《探矿工程》2005,32(6):34-37

为了满足可地浸砂岩铀矿的开采工艺要求，研制了HXY-800QT型拖车钻机。介绍了该钻机的设计思想、性能特点、主要部件的结构设计及生产使用情况。  相似文献   

关于薄壁金刚石钻头胎体性能的探讨          下载免费PDF全文

王生福 《探矿工程》2005,32(11):57-58

对薄壁金刚石钻头胎体进行了性能分析和配方设计探讨，尤其根据被钻切介质对钻头胎体性能的要求作了较详细的分析，从理论分析结合实践经验筛选出了钻切建筑石材和各种钢筋砼的钻头胎体配方，在生产中满足了钻头工作条件的要求。  相似文献