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The Upper Permian Sedimentary Facies and Its Role in the Dajing Cu-Sn Deposit, Linxi County, Inner Mongolia, China 总被引:3,自引:1,他引:3
Gongjiong QIN Yosuke KAWACHI Liqing ZHAO Yongzheng WANG Qiang OU 《Resource Geology》2001,51(4):293-305
Abstract: Exhaustive investigations were launched for confirming the upper Permian host rocks of the Dajing Cu-Sn Deposit, probing into the possibility that Dajing is a Sedex type deposit during cosedimentation, complementing the deficiency of previous researches and going further into substantiating the role of the upper Permian strata in the control of ore distribution. After more than two years work, we reclassified the sedimentary facies in the Dajing area and its periphery as shallow fresh water lake and delta. Indicative sedimentary structures, such as ripple marks, rain marks, and mud cracks combined with contemporary fossils, were revealed. Having measured the flow directions, performed chemical comparison, and analyzed various sediments from sourceland in the Dajing area by XRF, we consequently redivided the strata into four sedimentary members, among which P2 l1 and P2 l2 were concluded as significant ore-hosted strata. The upper Permian basin was a lateral rift basin. The water and sediments in the basin are much deeper and thicker in the north than those in the south.
The indicators of special sedimentary facies, such as gravity flow, brine pool and synchronogenic stratiform structure of the ore cannot be found in the Dajing area. There was no growth fault, assemblage of sulfide and sulfate, and no zonation as well.
On the basis of study in this area, taking into account the paleosedimentary environment as capriciously flowing shallow lake, which approximated the state of oxidation, we figured that the paleogeography made it prohibitively difficult to form stratiform sulfide deposits which are prone to form in deoxidized environment. It can be ruled out the possibility that the Dajing deposit is a syngenetic deposit during sedimentation. 相似文献
The indicators of special sedimentary facies, such as gravity flow, brine pool and synchronogenic stratiform structure of the ore cannot be found in the Dajing area. There was no growth fault, assemblage of sulfide and sulfate, and no zonation as well.
On the basis of study in this area, taking into account the paleosedimentary environment as capriciously flowing shallow lake, which approximated the state of oxidation, we figured that the paleogeography made it prohibitively difficult to form stratiform sulfide deposits which are prone to form in deoxidized environment. It can be ruled out the possibility that the Dajing deposit is a syngenetic deposit during sedimentation. 相似文献
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<正>Corrigendum to:Chinese Journal of Oceanology and Limnology Vol.33 No.1,P.551-551,2015http://dx.doi.org/10.1007/s00343-014-3338-5The presentation of Eq.1 in Section 2 on page 263 was incorrect in the hardcopies.The correct version is given below. 相似文献
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采用罗德里格矩阵公式,在不考虑尺度因子的情况下,建立了基于罗德里格矩阵的六参数坐标转换模型,推导了高精度参数初值计算方法,最小二乘迭代法平差公式。通过实测数据验证,通过实测数据计算,表明该算法具有精度高、稳定性强、适用性广等优点。 相似文献
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The Proterozoic was the first of severa1 impor-tant transitional periods in the earth's evolutionaryhistory. Linear .rifts over1apped on the b4se ofArchean granite -- greenstone and high -- grade gneissregimes. Along with the formation and evolution ofthe… 相似文献
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西太平洋暖池区是指位于热带西太平洋及印度洋东部海表温度常年在28 ℃以上的海域,是全球海表温度最高的深海区,构造环境与沉积环境复杂,沉积物中的生物组分含量差异较大,生物组分会对深海沉积物物理力学性质产生显著影响,但目前对沉积物中生物组分含量和沉积物物理力学性质之间的相关性关系尚不明确。本文对西太平洋暖池区核心部位的表层沉积物样品进行现场物理力学性质测试和室内涂片鉴定,研究深海表层沉积物的物理力学性质与生物组分之间的关系。结果表明:研究区表层沉积物含水率范围为61.1%~435.1%,天然密度范围为1.04~1.76 g/cm3,贯入阻力范围为0~100 kPa,十字板剪切强度范围为0~8.6 kPa,整体具有高含水率、低密度、低强度等典型的深海沉积物物理力学性质特点。西加洛林海脊、海山等CCD以浅的区域为钙质生物组分>50%的钙质沉积区;西加洛林海槽西南部及其周边的深水沟槽地区一般为硅质生物组分>50%的硅质沉积;西加洛林海盆内部则主要为黏土沉积区。随钙质生物组分减少和硅质生物组分增多,表层沉积物类型分别为钙质沉积物、黏土沉积物和硅质沉积物,天然含水率变高,天然密度、贯入阻力和十字板剪切强度降低,表明深海表层沉积物的物理力学性质与生物组分含量密切相关:贯入阻力、十字板剪切强度、天然密度与钙质生物组分含量呈正相关,与硅质生物组分含量呈负相关;而天然含水率正好相反,与钙质生物组分含量呈负相关,与硅质生物组分含量呈正相关。本文建立了深海沉积物中生物组分与物理力学性质之间的相关关系,提出了沉积物生物组分含量与物理力学性质之间的拟合公式,可以为深海沉积物工程性质的评价提供参考。 相似文献
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利用C-F模型识别僵尸网络迁移 总被引:1,自引:1,他引:0
基于C-F模型识别僵尸网络的迁移,以僵尸网络迁移过程中表现出的多个特征为基础,提出了一种识别僵尸网络迁移的方法,能够协同多个特征判断给定的两批僵尸主机是否具有迁移关系。通过几个典型僵尸样本的评测,有效地识别了僵尸网络的迁移行为。与单纯采用IP地址重合度的方法进行了对比,在僵尸网络成员数量动态变化的情况下,仍然保持了理想的识别结果。 相似文献
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基于海底现场取土样,利用GDS高压三轴试验仪重塑不同压力条件下的海洋土,在此基础上通过三轴加卸载试验,模拟研究高压海洋土在非保真取样过程中的卸荷响应特性,即围压-土样体积变化规律。饱和土样总体积变化一般可用反压体积变化近似描述,本文进一步考虑了高压水可压缩性的影响。通过不同加卸载循环次数以及卸载时间等的试验,表明其对高压试验结果影响很小,不同初始围压与孔压土样的卸荷试验则表明了孔压越大土样体积变化越明显等特点。卸载试验总的特征为:高压卸载过程中土样体积膨胀开始慢,发展逐渐变快,至尾段变化最快;不同作用因素对卸载中间阶段影响明显,而对初始段和末尾段影响不明显,这与中低压卸载特性存在一定区别。 相似文献