Guo C.-Y.,Geological Institute of Gold |
Guo C.-Y.,State Key Laboratory of Geological Processes and Mineral Resources |
Guo C.-Y.,China University of Geosciences |
Guo C.-Y.,Beijing University of Technology |
And 10 more authors.
Kuangwu Yanshi/ Journal of Mineralogy and Petrology | Year: 2011
On the basis of review of recent advances on tracing ore forming fluid by using widely adopted δD vs δ 18O system,attempt is made to discuss the reliability ofδD vs δ 18O system in tracing ore forming fluid of hydrothermal mineral deposits. Following questions related to the problems were proposed. (1) Water δ 18O calculation from quartz δ 18O is suspected in the subjective determination of isotopic equilibrium temperature; because it is difficult in determining whether the oxygen isotope equilibrium between quartz and water is achieved. Sometimes, the same quartz δ 18O data produce different δ 18O liquid and result in different temperatures, which obtain a confused recognition of mixture of ore fluid with meteoric water in later stage. (2) Duo to crystal defects, quartz usually contains structural bonded water which is able to release from quartz in thermal decrepitating process. The released structural water is likely to alter significantly the δD measurement of inclusion fluid in quartz. However,most of the published data did not illuminate clearly the explosion temperatures. This prevent the evaluation how much the structural OH has been involved. (3) Quartz is not a well closed host mineral for fluid inclusion;it is easy to exchange with outside materials. The mixed liquid can not represent the original ore forming fluid and therefore, the reliability of SD measurement from fluid inclusion in quartz is doubtful. (4) The δD calculation from hydrothermal OH bearing silicate minerals are ambiguous in tracing ore forming fluid, because the pressure effect on D/H fractionation between silicate minerals and water at high temperatures are not taken into consideration. It is recommended that systematic analysis and effort on δD-δ 18O from inclusion fluid in sulfide should be explored, coupled with minor volatile ratios and He-Ar isotope compositions,to trace the origin of ore forming fluid of hydrothermal ore deposits.
Shibin L.,Gold Mines Unit |
Min Q.,Geological Institute of Gold |
Cuiyi N.,Geological Institute of Gold |
Liang W.,Geological Institute of Gold
Acta Geologica Sinica | Year: 2016
In China, there are 12 types of gold deposits in 57 class-III metallogenic zones, formed in 7 main metallogenic periods. Most gold deposits are small or occur as ore spots; very large deposits are rare with relatively poor quality, mainly medium to low grade. Only 35% of the total gold reserves is identified, while a large amount of reserves is yet to be identified. In recent years, China Geological Survey has organized or conducted mineral resources survey and evaluation project, replacement resources prospecting for deposits in crisis, old mines prospecting and commercial prospecting funded or encouraged by the Central Government. These efforts have been fruitful. According to the temporal and spatial allocation of gold resources, and experiences from recent prospecting efforts, western China and the deep layers and peripheries of the-sits in eastern China have relatively high prospecting potential. The government should give even more support to the gold industry and strengthen technological innovation to help address difficulties in gold exploitation and processing. The government should also formulate consistent plans, consolidate mining rights, and promote integrated exploration, so as to achieve new major breakthroughs in gold prospecting. Gold is both a form of material wealth and a way of storing wealth. It is a rare resource with dual functions of commodity and currency. As an important global strategic asset and a cornerstone of financial reserves, gold plays an irreplaceable role in securing national economic development, maintaining financial security, strengthening national comprehensive power and promoting RMB internationalization. Based on latest research and prospecting results, the thesis proposes preliminary conclusions on types, temporal and spatial allocation, and exploration and development of gold deposits in China; predicts China's gold resource potential; reviews recent gold prospecting and exploration efforts; and, in the hope of offering some reference for the new round of gold prospecting, exploration and planning, offers some suggestions. © 2016 Geological Society of China