Research Progress on the Application of Strontium Isotope Analysis Techniques in Geology: A Review

Strontium (Sr) isotopes have unique geochemical properties, such as time dependence and environmental sensitivity. With the development of testing technology and theoretical systems, using Sr isotopes has become a key technique in geoscience research. However, due to the abnormal interference of the Sr isotope ratio in the complex environment, it may be challenging to appropriately interpret some geological evolution processes using conventional analytical results based on thermal ionization mass spectrometer (TIMS) or multicollector inductively coupled plasma-mass spectrometer (MC-ICP-MS). Based on the inherent properties and evolutionary characteristics of Sr isotopes, the sample preparation and measurement methods in the process of Sr isotope analysis are summarized, and the latest progress and understanding of Sr isotope in stratigraphy, petrology, ore deposit science and hydrogeology are expounded. It is pointed out that Sr isotope stratigraphy has formed a time series map containing the changes of Sr isotope in seawater from 509 million years to the present. When Sr isotopes are employed as a stratigraphic index, it must be properly corrected and interpreted in accordance with a particular geological context because it is influenced by a variety of processes, including weathering and magmatic interference. In the field of petrology, the diagenetic processes of sedimentary rocks, the genesis of various rock types, changes in the paleoenvironment, and crustal tectonic activity are all typically distinguished using Sr isotopes. However, the information provided by Sr isotopes is insufficient to precisely describe the creation of rocks because of the impact of weathering and metamorphism. Sr isotopes are used in the field of ore deposit science to determine the source of ore-forming materials, the process of fluid evolution, and the genetic type of ore deposit. However, at high temperatures, diffusion and mineral recombination can cause the Rb-Sr isotope system to reset, which can interfere with determining the age of the material. The complicated groundwater system may make it challenging to interpret Sr isotopes, which is used in hydrogeology to examine the origin of groundwater and the water-rock interaction. Therefore, the following recommendations for future research are proposed: to reconstruct the accurate history of the paleomarine Sr isotope ratio, to uncover the mechanism of Sr isotope fractionation at varying temperatures, and to develop fine Sr isotope tracer technology to overcome the limitations of current Sr isotope research. The advancement and utilization of Sr isotope theory has been strengthened by this review.