Recently, with the increasing use of TEM technique in mineralogy, more and more space groups of high-temperature phases and low-temperature phases and the domain structures of phase transitional minerals have been det...Recently, with the increasing use of TEM technique in mineralogy, more and more space groups of high-temperature phases and low-temperature phases and the domain structures of phase transitional minerals have been determined. Therefore, on the basis of summarizing the numerous results of individual minerals, it is necessary to discuss the relationship between the types of space groups of two phases and the nature of展开更多
Basaltic columnar jointing is a protogenetic-tensile-cracking structure of basalt, which includes two tiers of polygonal (usually hexagonal) prisms with their thickness and length being different. The origin of column...Basaltic columnar jointing is a protogenetic-tensile-cracking structure of basalt, which includes two tiers of polygonal (usually hexagonal) prisms with their thickness and length being different. The origin of columnar jointing had been explained by the traditional hypothesis of cooling-contraction for a long time. In 1981, the hypothesis of double-diffusive convection, which is analogous to the theory of salt fingers in marine physics, was proposed by Kantha, and 'basalt fingers'—a new concept was adopted.展开更多
Domain structures in mineral crystals could be categorized into three groups and several subgroups within each group, based on characteristics of domain structures and mechanisms causing domain structures: (ⅰ) domain...Domain structures in mineral crystals could be categorized into three groups and several subgroups within each group, based on characteristics of domain structures and mechanisms causing domain structures: (ⅰ) domain structures constituted by domains with the same (or identical) crystal structure and chemical composition, including anti-phase domain structures, twinning domain structures, inversion domain structures, and translationtwinning domain structures; (ⅱ) domain structures constituted by two or more than two kinds of domains with the same chemical composition but different crystal structures; and (ⅲ) domain structures constituted by two kinds of compositional and structural different domains, including exsolution-induced and polysomatic reaction-induced domain structures. Different types of domain structures may display different phenomena in their TEM images and SAED patterns, due to different crystallographic characteristics of different domain structures. The domain structures in minerals may affect physical properties, chemical composition, and thermodynamic properties of minerals, and can also indicate the evolution history of minerals.展开更多
基金Project supported by the National Natural Science Foundation of China
文摘Recently, with the increasing use of TEM technique in mineralogy, more and more space groups of high-temperature phases and low-temperature phases and the domain structures of phase transitional minerals have been determined. Therefore, on the basis of summarizing the numerous results of individual minerals, it is necessary to discuss the relationship between the types of space groups of two phases and the nature of
文摘Basaltic columnar jointing is a protogenetic-tensile-cracking structure of basalt, which includes two tiers of polygonal (usually hexagonal) prisms with their thickness and length being different. The origin of columnar jointing had been explained by the traditional hypothesis of cooling-contraction for a long time. In 1981, the hypothesis of double-diffusive convection, which is analogous to the theory of salt fingers in marine physics, was proposed by Kantha, and 'basalt fingers'—a new concept was adopted.
基金This research program was supported by the National Natural Science Foundation of China, and Laboratory of Solid State Microstructures of Nanjing University.
文摘Domain structures in mineral crystals could be categorized into three groups and several subgroups within each group, based on characteristics of domain structures and mechanisms causing domain structures: (ⅰ) domain structures constituted by domains with the same (or identical) crystal structure and chemical composition, including anti-phase domain structures, twinning domain structures, inversion domain structures, and translationtwinning domain structures; (ⅱ) domain structures constituted by two or more than two kinds of domains with the same chemical composition but different crystal structures; and (ⅲ) domain structures constituted by two kinds of compositional and structural different domains, including exsolution-induced and polysomatic reaction-induced domain structures. Different types of domain structures may display different phenomena in their TEM images and SAED patterns, due to different crystallographic characteristics of different domain structures. The domain structures in minerals may affect physical properties, chemical composition, and thermodynamic properties of minerals, and can also indicate the evolution history of minerals.
