- 责任者：Yang Xiaozhi (State Key Laboratory for Mineral Devasits Research ; School of Earth Sciences and Engineering ; Nanjing University ; Nanjing 210046 ; China)
- 刊名：Acta Petrologica et Mineralogica
- 出版年：2013
- 卷期：32(5)
- 关键词：上地幔 ; upper mantle ; 电导率 ; electrical conductivity
- 页码：p.663-679
- 图表：8 illus., 105 refs.
- 分类号：0400
- issnNo：ISSN1000-6524
- isbnNo：CN11-1966/P
Anomalous zones of high electrical conductivity and pronounced electrical anisotropy have been detect- ed by geophysical electromagnetic deep surveys in some regions of the uppermost mantle; nevertheless, their ori- gin remains a long-standing controversial issue. Several conduction mechanisms have been proposed, such as the presence of partial melts, H-bearing olivine, graphite and sulfides in grain boundaries, Fe-rich garnet and hy- drous minerals like micas. The differences between these models have significantly different impacts on the com- position, structure and physical-chemical properties of the uppermost mantle, and even on the triggering of earthquakes and the styles of mantle convection and other dynamical processes. Based on recent studies of petro- logy, geochemistry, geophysics, numerical modeling and laboratory high-pressure and high-temperature experi- ments, this paper deals with various problems involved with the available models. The authors hold that electri- cal anomalies in some regions of the uppermost mantle may be related to its macro-scale heterogeneities, includ- ing the local enrichment of Fe3 ＋- and H20-rich augites （and other pyroxenite analogues） in the form of dykes/ veins and/or the local presence of remnants from recycled crustal materials （e. g., conductive subduction-associ- ated oceanic and continental crust and/or delaminated continental deep crust stretched into high aspect ratio bands/lenses due to mantle flow）. Electrical anomalies in different regions of the uppermost mantle may have different origins, and thus eeking for a single unique explanation seems unnecessary.