Geochronology is fundamental to understanding planetary evolution.However,as space exploration continues to expand,traditional dating methods,involving complex laboratory processes,are generally not realistic for unma...Geochronology is fundamental to understanding planetary evolution.However,as space exploration continues to expand,traditional dating methods,involving complex laboratory processes,are generally not realistic for unmanned space applications.Campaign-style planetary exploration missions require dating methods that can(1)rapidly resolve age information on small samples,(2)be applied to minerals common in mafic rocks,and(3)be based on technologies that could be installed on future rover systems.We demonstrate the application of rapid in situ microanalytical Lu–Hf phosphate geochronology using samples of pallasite meteorites,which are representative examples of the deep interiors of differentiated planetoids that are generally difficult to date.Individual pallasites were dated by laser ablation tandem mass-spectrometry(LA-ICP-MS/MS),demonstrating a rapid novel method for exploring planetary evolution.Derived formation ages for individual pallasites agree with traditional methods and have<2%uncertainty,opening an avenue of opportunity for remote micro-analytical space exploration.展开更多
Fluorite(CaF_(2))is a common hydrothermal mineral,which precipitates from fluorine-rich fluids with an exceptional capacity to transport metals and Rare Earth Elements(REEs).Hence,the ability to date fluorite has impo...Fluorite(CaF_(2))is a common hydrothermal mineral,which precipitates from fluorine-rich fluids with an exceptional capacity to transport metals and Rare Earth Elements(REEs).Hence,the ability to date fluorite has important implications for understanding the timing of metal transport in hydrothermal systems.Here we present,for the first time,fluorite Lu-Hf dates from fluorite-carbonate veins from the Olympic Cu-Au Province in South Australia.The fluorite dates were obtained in situ using the recently developed LA-ICP-MS/MS Lu-Hf dating method.A fluorite-calcite age of 1588±19 Ma was obtained for the Torrens Dam prospect,consistent with the timing of the formation of the nearby Olympic Dam iron-oxide copper gold Breccia Complex.Veins in the overlying Neoproterozoic successions were dated at 502±14 Ma,indicating a temporal link between Cu-sulphide remobilisation and the Delamerian Orogeny.Additionally,we present a multi-session reproducible date for magmatic fluorite from a monzogranite in the Pilbara Craton(Lu-Hf age of 2866±19 Ma).This age is consistent with a garnet Lu-Hf age from the same sample(2850±12 Ma)and holds potential to be developed into a secondary reference material for future fluorite Lu-Hf dating.展开更多
基金supported by the Institute for Mineral and Energy Resources (IMER)Australian Research Council (ARC) DP200101881
文摘Geochronology is fundamental to understanding planetary evolution.However,as space exploration continues to expand,traditional dating methods,involving complex laboratory processes,are generally not realistic for unmanned space applications.Campaign-style planetary exploration missions require dating methods that can(1)rapidly resolve age information on small samples,(2)be applied to minerals common in mafic rocks,and(3)be based on technologies that could be installed on future rover systems.We demonstrate the application of rapid in situ microanalytical Lu–Hf phosphate geochronology using samples of pallasite meteorites,which are representative examples of the deep interiors of differentiated planetoids that are generally difficult to date.Individual pallasites were dated by laser ablation tandem mass-spectrometry(LA-ICP-MS/MS),demonstrating a rapid novel method for exploring planetary evolution.Derived formation ages for individual pallasites agree with traditional methods and have<2%uncertainty,opening an avenue of opportunity for remote micro-analytical space exploration.
基金supported by research grants DP200101881 and FT210100906 from the Australian Research Council(ARC)and additionallythe Mineral Exploration Cooperative Research Centre.
文摘Fluorite(CaF_(2))is a common hydrothermal mineral,which precipitates from fluorine-rich fluids with an exceptional capacity to transport metals and Rare Earth Elements(REEs).Hence,the ability to date fluorite has important implications for understanding the timing of metal transport in hydrothermal systems.Here we present,for the first time,fluorite Lu-Hf dates from fluorite-carbonate veins from the Olympic Cu-Au Province in South Australia.The fluorite dates were obtained in situ using the recently developed LA-ICP-MS/MS Lu-Hf dating method.A fluorite-calcite age of 1588±19 Ma was obtained for the Torrens Dam prospect,consistent with the timing of the formation of the nearby Olympic Dam iron-oxide copper gold Breccia Complex.Veins in the overlying Neoproterozoic successions were dated at 502±14 Ma,indicating a temporal link between Cu-sulphide remobilisation and the Delamerian Orogeny.Additionally,we present a multi-session reproducible date for magmatic fluorite from a monzogranite in the Pilbara Craton(Lu-Hf age of 2866±19 Ma).This age is consistent with a garnet Lu-Hf age from the same sample(2850±12 Ma)and holds potential to be developed into a secondary reference material for future fluorite Lu-Hf dating.
