PHEOLOGY OF SOLID MATERIALS OF DEEP EARTH'S INTERIOR

地球内部流变学研究的主要主题是研究矿物和岩石的塑性和脆性变形的物理机制。自1970年以来，对行星和地球材料的流变性进行了实验研究。最近关于这一主题的精确实验从1978年开始在麻省理工学院、澳大利亚国立大学、加州大学南加州分校和德克萨斯大学(卡拉托和托里乌米)进行。此外，在脆性领域，摩擦滑移行为由德州AM(Logan和Shimamoto)精确确定。Shimamoto(1986)提出了脆韧性转变过程中的剪切不稳定性。在这些实验研究之后，提出的热点讨论概括如下：超高压矿物的流变学，流动规律的压力依赖性，矿物的水解弱化，塑性和摩擦不稳定性，脆韧转变区材料的本构关系，多相和多晶集合体的流变学。在这项资助的研究中，我们进行了变形mec…更多的超高压矿物，如石榴石，使其成为分子动力学、位错运动的模拟器，以及多相和多晶聚集体的计算机模拟。通过这项研究，晶体位错的引入需要非常快的超级计算机很长的CPU时间。例如，即使使用100 Mflop(双倍)CPU，1000粒子MD模拟每1步也需要12.5秒。为此，我们研制了一种新型的专用后端计算机，该计算机由5(6)台Transputer(英国INMOS的T800)并联而成。这台后端并行计算机的处理能力约为10Mflop和100Mips。仿真语言为3L公司的并行Fortran。石榴石的流变性对推断上、下地幔过渡层的性质具有重要意义。我们提出了石榴石的非常硬的流变学，这是由于电子显微镜所指认的石榴石中膨胀位错的速度很慢所致。石榴石形成于10-16 Gpa和1600℃，表明少量辉石和辉石与大多数石榴石具有很大的岩石学反差。为了获得大量下地壳变质作用和俯冲碰撞带构造研究的自然数据，我们在松江召开了涉及变形和反应的变质岩PT-T-T轨迹精确测定研讨会。研讨会非常令人兴奋和成功。阐明了反应和变形是相互交织的。较少

Main theme of this group research on rheology of the Earth's interior are focused on studying physical mechanisms of plastic and brittle deformation of minerals and rocks. Since 1970,rheology of planetary and Earth's materials has been investigated experimentally. Recent precise experiments on this subject began to perform from 1978 at MIT,ANU,UCSA and UT(Karato and Toriumi). Furthermore,in the brittle field frictional slip behavior were determined exactly by Texas AM(Logan and Shimamoto). Shimamoto(1986) proposed shear instability in the brittle-ductile transition regime. After these experimental investigations,hot discussions proposed are summarized as follows;rheology of ultrahigh pressure minerals,pressure-dependence of flow law,hydrolytic weakening of minerals, Plastic and frictional instability,constituitive law of materials in the brittle-ductile transition regime, rheology of polyphase and polycrystallinc aggregates.In the study of this grant-in-aid we conducted deformation mec … More hanisms of ultrahigh pressure minerals such as garnet and make a simulator of molecular dynamics dislocation motion and computer simulation of polyphase and polycrystalline aggregates. By this investigations introduction of crystal dislocation requires for very long cpu times of very fast super computer. For examples,1000 particles MD simulations need 12.5 seconds per 1 step even by 100 Mflops(double)cpu. Thus,we made a new type special backend computer equiped on microcomputer which is composed of parallel-connected 5(6) transputers(T800 of INMOS,England). The ability of this backend parallel computer is about 10 Mflops and 100 Mips. Language for simulation is parallel fortran of 3L company. This backend machine can be applied to simulate the polyphase flow.Rheology of garnet is quite important to infer the nature of transition layer of upper and lower mantle. We proposed very hard rhcology of garnet due to very slow velocity coming from expanded dislocations in garnet which were assigned by TEM. Garentite formed under 10-16GPa and 1600 C indicated a great contrast of rhcology between small amount of pyroxene and stishovite,and majority garnet.To get a natural data derived from many studies of lower crust metamorphism and tectonics of subduction and collision zones,we convened the workshop of Precise determination of P T t paths of metamorphic rocks involving deformation and reaction at Matsue. The workshop was very excited and successful. It is clarified that reaction and deformation is interlocked with each other. Less