差应力状态对岩石熔融程度的影响——以黑云母片麻岩的动、静态熔融对比实验为例  

Effect of Differential Stresses on the Degree of Melting:Case Study of Melting Experiment of Biotite Gneiss

作　　者：马瑞[1] 刘正宏[1] 吕古贤[2] 张刚[1] 

机构地区：[1]吉林大学地球科学学院,长春130061 [2]中国地质科学院地质力学研究所,北京100081

出　　处：《地质学报》2005年第3期338-341,i003-i004,共6页Acta Geologica Sinica

基　　金：国家自然科学基金项目(编号49872024);国土资源部重点科技发展计划项目(编号200220)资助的成果

摘　　要：以河北省平山县阜平群的黑云片麻岩为实验样品,有差应力条件下的动态实验,围压10MPa,温度800℃条件下,施加相当于差应力为0～25MPa,且以每5MPa为间隔进行了天然块状岩石样品的动态熔融,在相同的围压条件下,温度由800～900℃每20℃为间隔,进行了无差应力条件下天然块状岩石的静态熔融实验,并进行了对比研究。结果表明,在相同温度条件下,岩石的熔融程度随着差应力的增加明显增高,当差应力达到25MPa时,800℃条件下岩石的熔融程度与900℃静态熔融条件下岩石的熔融程度相当。实验力学分析计算表明,动态实验中构造附加压力增加了围压,差应力每增加5MPa相当于1.67MPa的增压,其与静态实验中温度升高20℃的效果一样。该实验结果对研究岩石深熔作用的深度问题有一定的参考意义。Comparative experiments of dynamic melting, at confining pressure of 10 MPa, temperature of 800℃ and differential stresses between 0～25 MPa with a stress increment of 5 MPa, and static melting, at the same confining pressure but varying temperature between 800℃ and 900℃ with a temperature increment of 20℃, are done on biotite gneiss samples from the Fuping Group in Pingshan Country, Hebei Province. It is shown that the degree of melting of the samples increase obviously with increasing differential stresses at the same temperature. The melting of rock at 800℃, when differential stresses achieve 25 MPa, is similar to the static melting at 900℃. It is shown that the effect of the increase of differential stresses of 5 MPa is in accordance to that of the increase of temperature of 20℃. This experimental result is significant to study the depth of remelting.

关 键 词：片麻岩 应力状态 对比实验 黑云母 动态实验 应力条件 差应力 实验样品 岩石样品 围压条件 熔融实验 对比研究 温度条件 熔融条件 力学分析 附加压力 温度升高 静态实验 深熔作用 20℃ 900 阜平群 平山县 河北省 计算表 

分 类 号：P589[天文地球—岩石学]