A geologic time scale is a chronological system that separates the geological strata of a planetary body into different units in temporal sequence and shows its progressive evolution.The time scale of the Moon was est...A geologic time scale is a chronological system that separates the geological strata of a planetary body into different units in temporal sequence and shows its progressive evolution.The time scale of the Moon was established a half-century ago during the telescopic-early Apollo exploration era,using data with limited spatial coverage and resolution.The past decades have seen a wide array of studies,which have significantly extended our understanding of global lunar geologic evolution.Based on a comprehensive review of lunar evolution with respect to the dynamical changes,we propose two major updates to the current lunar time scale paradigm to include the evolution of both endogenic and exogenic dynamic forces now known to have influenced early lunar history.Firstly,based on the temporal interplay of exogenic and endogenic processes in altering the Moon,we defined three Eon/Eonothem-level units to represent three dynamical evolutionary phases.Secondly,the pre-Nectarian System is redefined and divided as the magma ocean-era Magma-oceanian System and the following Aitkenian System beginning with the South Pole-Aitken basin.The ejecta of this basin,Das Formation,was deposited on the primordial lunar crust as the oldest stratum produced from exogenic processes.The updated lunar time scale,facilitated by the post-Apollo exploration and research advances,provides an integrated framework to depict the evolution of the Moon and has important implications for the geologic study of other terrestrial planets.展开更多
It has long been a controversy about the source of ore\|forming materials of Au\|Ag polymetallic deposits both in metallogenic theory and in ore\|searching practice. In terms of a large wealth of the isotopic statisti...It has long been a controversy about the source of ore\|forming materials of Au\|Ag polymetallic deposits both in metallogenic theory and in ore\|searching practice. In terms of a large wealth of the isotopic statistics data from Indosinian\|Yanshanian endogenic ore deposits in northern Hebei (generally referring to the areas along the northern part of Taihang Mountains and northern Hebei, the same below), it is considered that the ore\|forming materials came from the deep interior of the Earth, which had migrated through plumes to the Earth surface while experienced multi\|stage evolution and then emplaced progressively in favorable structural loci to form ores. Their isotope data show that 559 sulfur isotopic data from 40 ore deposits are, for the most part, within the range of -5‰- 5‰, with a high degree of homogenization, indicating that the sulfur is derived mainly from magma; 200 lead isotope data from 37 ore deposits indicate that the ore\|forming materials are principally of mantle source though some crust\|source material was involved; 96 oxygen, hydrogen and carbon isotope data from 34 ore deposits illustrate that the ore\|forming fluids are dominated by magmatic water while other sources of water would be involved. It may therefore be seen that the formation of endogenic deposits has nothing to do with the strata .展开更多
基金This work was supported partly by the National Key Research and Development Program of China(Grant No.2022YFF0503100)the B-type Strategic Priority Program of the Chinese Academy of Sciences(Grant No.XDB41000000)+1 种基金the National Natural Science Foundation of China(Grant Nos.41902317,41941002,41773065)the National Science and Technology Infrastructure Work Projects(Grant No.2015FY210500).
文摘A geologic time scale is a chronological system that separates the geological strata of a planetary body into different units in temporal sequence and shows its progressive evolution.The time scale of the Moon was established a half-century ago during the telescopic-early Apollo exploration era,using data with limited spatial coverage and resolution.The past decades have seen a wide array of studies,which have significantly extended our understanding of global lunar geologic evolution.Based on a comprehensive review of lunar evolution with respect to the dynamical changes,we propose two major updates to the current lunar time scale paradigm to include the evolution of both endogenic and exogenic dynamic forces now known to have influenced early lunar history.Firstly,based on the temporal interplay of exogenic and endogenic processes in altering the Moon,we defined three Eon/Eonothem-level units to represent three dynamical evolutionary phases.Secondly,the pre-Nectarian System is redefined and divided as the magma ocean-era Magma-oceanian System and the following Aitkenian System beginning with the South Pole-Aitken basin.The ejecta of this basin,Das Formation,was deposited on the primordial lunar crust as the oldest stratum produced from exogenic processes.The updated lunar time scale,facilitated by the post-Apollo exploration and research advances,provides an integrated framework to depict the evolution of the Moon and has important implications for the geologic study of other terrestrial planets.
文摘It has long been a controversy about the source of ore\|forming materials of Au\|Ag polymetallic deposits both in metallogenic theory and in ore\|searching practice. In terms of a large wealth of the isotopic statistics data from Indosinian\|Yanshanian endogenic ore deposits in northern Hebei (generally referring to the areas along the northern part of Taihang Mountains and northern Hebei, the same below), it is considered that the ore\|forming materials came from the deep interior of the Earth, which had migrated through plumes to the Earth surface while experienced multi\|stage evolution and then emplaced progressively in favorable structural loci to form ores. Their isotope data show that 559 sulfur isotopic data from 40 ore deposits are, for the most part, within the range of -5‰- 5‰, with a high degree of homogenization, indicating that the sulfur is derived mainly from magma; 200 lead isotope data from 37 ore deposits indicate that the ore\|forming materials are principally of mantle source though some crust\|source material was involved; 96 oxygen, hydrogen and carbon isotope data from 34 ore deposits illustrate that the ore\|forming fluids are dominated by magmatic water while other sources of water would be involved. It may therefore be seen that the formation of endogenic deposits has nothing to do with the strata .
