阿尔泰成矿区大型、超大型矿床成矿规律综合信息研究

在综合信息矿产预测理论与方法指导下,通过地质、物探、化探资料综合信息解译工作,对阿尔泰成矿区大型、超大型矿床成矿规律进行了综合研究。绝大多数金、铜、铅（锌）矿床具有相同或相似的控矿因素,矿床我有共生或伴生的特点。它们处于：大地构造相对抬升的单元背景;不同大地构造单元相结合的部位;前寒武系变质岩系出露基底和隐伏基底及其边缘;泥盆纪火山岩或沉积岩组成的盆地边缘;中酸性继承性岩体及其接触带附近;重力场梯度带附近与重、磁资料推断相吻合的断裂构造及交汇处,以晚期重、磁构造为主;高、中、低温元素组合异常汇水盆地密集区。     

继承性构造与新生构造并存的时空发育特征及其油气勘探意义

中国及邻区大陆是经多期造山运动形成的复合大陆,后期构造可分为继承性构造和新生构造两种。两者在空间上的并存关系较为复杂,新生构造发育的强度可因地而异。东部新生代盆地(如苏北和渤海湾盆地),北东向构造属继承性构造,北北东向构造是新生构造,油气勘探的优选靶区是叠加在继承性构造之上的新生构造。中—东部的中生代盆地(如二连和鄱阳盆地)的油气勘探,除了寻找叠加在继承性构造之上的新生构造外,还应注意新生构造的发育引起的油气调整或晚期次生成藏。海相沉积盆地常上叠有陆相沉积盆地,因而发育多期多方向的新生构造并分别控制了岩性油藏和构造油藏的形成,如四川盆地东北部的两期(北西向和北东向)新生构造。以构造为主线,加强新生构造的解析并结合"源"、"运"和"聚"的研究,"盆"山"耦合理论将在生产实践中进一步显现其指导意义。     

招远—莱州地区花岗岩类继承锆石年龄及其意义

招远—莱州地区花岗岩类锆石 Ｓ Ｈ Ｒ Ｉ Ｍ Ｐ 研究表明,该区花岗岩类含有大量不同时代的继承锆石。３４４６ ±２ Ｍａ ～３１１４ ±４ Ｍａ 继承锆石的发现,表明鲁东地区存在古太古代硅铝核。大量印支期继承锆石的年龄（ 平均年龄２１９ Ｍａ） 与华南、华北克拉通碰撞时代一致,推测这些锆石极可能来自其源岩———华南、华北克拉通碰撞造山花岗岩,从而否定了玲珑型花岗岩主要是由胶东岩群交代 重熔形成的传统认识。郭家岭型花岗闪长岩中含有较多新太古代和古元古代继承锆石,表明其源岩有较多的胶东岩群和荆山岩群变镁铁质岩石和（ 或） Ｔ Ｔ Ｇ 岩系的硅铝质岩石。     

Zircon Hf isotope composition of metamorphic eclogite from Xindian,Dabie Terrain

Hf isotope measurement has been carried out for UHP metamorphic eclogite from Xindian by using LA-MC-ICP-MS technique. The result indicates that metamorphic growth zircon has high 176Hf/177Hf (0.282544―0.282612) and low 176Lu/177Hf (0.000004―0.000211) ratio,inherited and recrystallized proto-lith zircon has low 176Hf/177Hf (0.282266―0.282466) and high 176Lu/177Hf (0.000090―0.002144) composi-tions. The low 176Lu/177Hf of growth zircon comes from its decreasing of Lu and increasing of Hf during UHP process. The high 176Hf/177Hf deduced from high radiogenic 176Hf,which was produced from long-term evolution of high Lu/Hf ratio minerals. Partial recrystallization of protolith zircon would not cause reworking of Lu/Hf isotope in zircon. Compared to U-Pb,zircon Lu-Hf system has better stability. The initial Hf isotope composition of metamorphic growth zircon may represent the Hf isotope compo-sition of whole rock system at the same time. The initial εHf of 3.0 for metamorphic precursor formation of Xindian eclogite indicates that the source material mainly derived from weak depleted mantle or mixing of depleted mantle with old crust.     

四川西部现今地壳形变与地震

采用分段线性速率动态平差法处理了川西地区７０年代以来的多期区域垂直形变资料。在此基础上,通过垂直形变场的信息分离与动态特征研究,定性、定量相结合分析了川西地区地壳运动现状及未来地震危险区。结果表明：川西地区现今地壳形变场出现转折,呈逆继承性运动,同时运动强度有所减弱。     

Neoproterozoic zircon inheritance in eastern North China craton (China) Mesozoic igneous rocks: derivation from the Yangtze craton and tectonic implications

We propose that inherited Neoproterozoic zircons in Mesozoic igneous rocks from the eastern portion of the North China craton (NCC) were initially derived from the Yangtze/South China block, rather than from the NCC itself. The mechanism that introduced these zircons into the NCC was likely tectonic underplating during Triassic continental subduction/collision of the Yangtze block beneath the NCC. The addition of abundant crustal materials represented by the exotic zircons, probably along the Moho or weak interfaces within the NCC crust, led to the crustal thickening of the NCC. These sialic materials contributed significantly to the Mesozoic igneous rocks, either as source rocks or as contaminants of magmas generated during an extensional environment following crustal thickening. Crustal thickening was spatially linked to lithospheric thinning, with both occurring mainly in the eastern segment of the NCC, suggestive of an intrinsic relationship between thickening and thinning events during Mesozoic evolution of the NCC.     

滑坡演化的逐代遗传模型

根据滑坡位移随时间逐次变化的规律,建立滑坡位移演化的逐代遗传模型,求解滑坡每代的位移和稳定系数。在此基础上对沪蓉西高速公路湖北宜昌－恩施段古树屋滑坡的位移变化进行了分析,结果表明,该模型的位移计算值结果较为理想,且简单可行,并通过对稳定系数的研究提出了滑坡稳定性判断的一个新依据。     

鄂东南地区存在古元古代—太古宙基底——来自铜鼓山岩体锆石U-Pb-Hf同位素的证据

对鄂东南地区位于毛铺—两剑桥断裂带上的铜鼓山岩体进行了野外地质及镜下显微研究及岩石化学分析, 重点分析了其中锆石U-Pb年龄和Hf同位素组成。结果表明铜鼓山岩体为石英闪长玢岩, 岩体形成于(147±2.6) Ma, 属晚侏罗世—早白垩世, 与鄂东南地区其它岩体年龄具有一致性。铜鼓山岩体中存在的大量继承锆石。分析的4个继承锆石形成于古元古代晚期1798~1888 Ma。继承锆石具有高的Th/U比值和极其相似的Lu-Hf同位素组成, 表明它们捕获于同一火成岩。这表明鄂东南地区存在古元古代基底。这些古元古代继承锆石低的εHf(t)值和冥太古代的Hf同位素两阶段模式年代暗示古元古代克拉通化是在太古宙基底上发展的。鄂东南地区和扬子陆块其它众多地区一样存在古元古代—太古宙基底。扬子陆块古元古代—太古宙基底极可能从四川盆地、鄂西崆岭和郧西地区东延至鄂东南地区。