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Spatial continuous modeling of early Cenozoic carbon cycle and climate

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National Science Review 2024年第4期11卷 30-32页

作者： Yonggang Liu Jian Zhang Haoyue Zuo Zhilin He Jiaqi Guo Qifan Lin Haonan Yu Jiawenjing Lan Jing Han Zhihong Song Zihan Yin Liang Zhao Yongyun Hu Zhengtang Guo Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of Physics Peking University Key Laboratory of Cenozoic geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences

The partial pressure of atmospheric CO2（pCO2） is determined by the carbon cycle that involves climate, biogeochemistry, and plate tectonics. In this cycle,atmospheric CO2is converted into organic carbon and carbonates by biological activities and silicate weathering, and buried as sediments. The sediments on the ocean floor are subducted into the Earth’s interior, and subsequently converted back into CO2and outgassed into the atmosphere.

关键词： ATMOSPHERIC CO2

Evaluation of 3D crustal seismic velocity models in southwest China:Model performance,limitation,and prospects

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Science China Earth Sciences 2024年第2期67卷 604-619页

作者： Xin WANG Ling CHEN Qi-Fu CHEN Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China

Southwest China is a tectonically and seismically active region,witnessing strong deformation due to the collision between the Indian and Eurasian *** the subsurface velocity structure of this region is thus important in understanding the tectonics and geodynamic processes of continental collision and in mitigating seismic *** studies have provided various 3D seismic velocity models in southwest ***,discrepancies exist among these models,and less effort has been made to quantify the reliability and accuracy of these existing velocity *** this study,we use regional 3D waveform simulation to evaluate the performance of various regional crustal 3D velocity models in reproducing observed *** particularly focus on two recent earthquake sequence in the region,the 2021.Yunnan Yangbi MS_(6.4) earthquake sequence and the 2022 Sichuan Luding MS_(6.8) earthquake *** tested 3D velocity models include the Southwest China Community Velocity model V1.0,the Unified Seismic Tomography Models for Continental China Lithosphere V2.0,the adjoint full waveform tomography model of the crustal and upper mantle beneath Eastern Tibetan Plateau,and the shallow seismic structure model beneath continental *** results show that the tested 3D velocity models generally capture well long-period(1. km)can improve the waveform fitting,emphasizing the importance of incorporating shallow structures in waveform *** full-waveform tomography model shows a slighter better performance than the other models,especially for the body-waves,highlighting the advantages

关键词： Southwest China Seismic tomography models Shallow Structures Waveform simulation Model evaluation

A two-step multi-frequency receiver function inversion method for shallow crustal S-wave velocity structure and its application across the basin-mountain range belts in Northeast China

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Science China Earth Sciences 2024年第3期67卷 687-703页

作者： Ruihao YANG Xu WANG Ling CHEN Mingye FENG Qifu CHEN State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

A shallow crustal velocity structure(above 1. km depth) is essential for understanding the crustal structures and deformation and assessing the exploration prospect of natural resources, and also provides priori information for imaging deeper crustal and mantle structure. Passive-source seismic methods are cost-effective and advantageous for regional-scale imaging of shallow crustal structures compared to active-source methods. Among these passive methods, techniques utilizing receiver function waveforms and/or body-wave amplitude ratios have recently gained prominence due to their relatively high spatial resolution. However, in basin regions, reverberations caused by near-surface unconsolidated sedimentary layers often introduce strong non-uniqueness and uncertainty, limiting the applicability of such methods. To address these challenges, we propose a two-step inversion method that uses multi-frequency P-RF waveforms and P-RF horizontal-to-vertical amplitude ratios. Synthetic tests indicate that our two-step inversion method can mitigate the non-uniqueness of the inversion and enhance the stability of the results. Applying this method to teleseismic data from a linear seismic array across the sedimentary basins in Northeast China, we obtain a high-resolution image of the shallow crustal S-wave velocity structure along the array. Our results reveal significant differences between the basins and mountains. The identification of low-velocity anomalies(1.) at depths less than 1.0 km beneath the Erlian Basin and less than 2.5 km beneath the Songliao Basin suggests the existence of sedimentary layers. Moreover, the high-velocity anomalies(~3.4–3.8 km s^(-1.) occurring at depths greater than 7 km in the Songliao Basin may reflect mafic intrusions emplaced during the Early Cretaceous. Velocity anomaly distribution in our imaging result is consistent with the location of the major faults, uplifts, and sedimentary depressions, as well as active-source seismic res

关键词： Receiver function Frequency dependence Two-step inversion Shallow crustal velocity structures Unconsolidated sedimentary basins

Enhancing the vertical resolution of lunar penetrating radar data using predictive deconvolution

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Earth and Planetary Physics 2024年第4期8卷 570-578页

作者： Chao Li JinHai Zhang CAS Engineering Laboratory for Deep Resources Equipment and Technology Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The Yutu-2 rover onboard the Chang’E-4 mission performed the first lunar penetrating radar detection on the farside of the *** high-frequency channel presented us with many unprecedented details of the subsurface structures within a depth of approximately 50 ***,it was still difficult to identify finer layers from the cluttered reflections and scattering *** applied deconvolution to improve the vertical resolution of the radar profile by extending the limited bandwidth associated with the emissive radar *** overcome the challenges arising from the mixed-phase wavelets and the problematic amplification of noise,we performed predictive deconvolution to remove the minimum-phase components from the Chang’E-4 dataset,followed by a comprehensive phase rotation to rectify phase anomalies in the radar ***,we implemented irreversible migration filtering to mitigate the noise and diminutive clutter echoes amplified by *** processed data showed evident enhancement of the vertical resolution with a widened bandwidth in the frequency domain and better signal clarity in the time domain,providing us with more undisputed details of subsurface structures near the Chang’E-4 landing site.

关键词： Chang’E-4 lunar penetrating radar data processing predictive deconvolution irreversible migration filtering

U-Pb dating of bastnäsite from the Vuoriyarvi massif:An example application for assessing the REE potential of carbonatite-related deposits

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Geoscience Frontiers 2024年第5期15卷 444-453页

作者： Evgeniy N.Kozlov Ekaterina N.Fomina Qiuli Li Jiao Li Geological institute Kola Science Centre of the Russian Academy of SciencesApatity 184209Russia institute of {1. and geophysics Chinese Academy of SciencesBeijing 100029China

The Vuoriyarvi massif is a Devonian multistage alkaline-ultrabasic carbonatite complex within the Kola alkaline *** carbonatites of the Vuoriyarvi massif contain abundant rare-earth mineralization mainly represented by ancylite-(Ce)and bastnäsite-(Ce).Ancylite was previously shown to have probably formed in the Devonian(ca.365 Ma)during an early postmagmatic *** geological observations have revealed a much later crystallization of bastnäsite but have not been able to specify the exact age of the *** in situ U-Pb dating of bastnäsite allowed us to constrain its ***äsite for this study was extracted from two varieties of dolomite carbonatite breccias cemented by(1.quartz-bastnäsite and(2)strontianite aggregates(hereafter bastnäsite-rich and strontianite-rich carbonatites–BRC and SRC,respectively).The obtained age estimations(237.7±9.8 Ma and 239.9±4.1.Ma,respectively)indicate that both studied rocks were formed during a single *** revealed age difference(~1.5 Ma)excludes the genetic link between the bastnäsite origin and regional alkaline magmatism,pointing out an additional source for the Vuoriyarvi bastnäsite-bearing ***,the obtained U-Pb ages provide strong evidence that a Triassic event is responsible for the occurrence of bastnäsite mineralization due to hydrothermal REE redistribution from the Devonian ancylite-rich *** of the REEs released during this process via dissolution of ancylite were precipitated in situ as bastnäsite,while strontium was transported and incorporated into *** Pb isotopic characteristics of bastnäsite(^(206)Pb/^(204)Pb=1..1.0.1.^(207)Pb/^(204)Pb=1..3±0.1.and^(207)Pb/^(206)Pb=0.84±0.01.are most probably inherited from the Devonian host rocks of the Vuoriyarvi massif involved in the Triassic *** signatures of Pb,Sr,and Nd show that the depleted mantle and lower crust played the leading role in formation of the Vuoriyarvi alkaline

关键词： Bastnäsite REE Carbonatites U-Pb dating Vuoriyarvi Kola alkaline province

New dating indicates intermittent human occupation of the Nwya Devu Paleolithic site on the high-altitude central Tibetan Plateau during the past 45,000 years

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Science China Earth Sciences 2024年第2期67卷 531-551页

作者： Junyi GE Xiaoling ZHANG Shejiang WANG Linhui LI Wei HE Yingshuai JIN Peiqi ZhANG Bing XU Chenglong DENG John WOLSEN Zhengtang GUO Xing GAO institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of SciencesBeijing 100044China University of the Chinese Academy of Sciences Beijing 100049China Tibetan Cultural Relics Conservation institute Lhasa 850000China Key Laboratory of Cenozoic geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences.Beijing 100029China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China School of Anthropology University of ArizonaTucson85721USA

The timing and mechanisms of the human occupation of the demanding high-altitude Tibetan Plateau environment are of great ***,we report on our reinvestigations and dating of the Nwya Devu site,located nearly 4600 meters above sea level on the central Tibetan Plateau.A new microblade techno-complex was identified on a lower lake shore at this site,distinct from the previously reported blade tool *** two lithic assemblages were dated to 45.6±2.6 and1..3±0.5 ka using optically stimulated luminescence and accelerator mass spectrometry^(1.)C *** represent,respectively,the earliest known Paleolithic and microlithic sites on the interior Tibetan Plateau,indicating multiple occupation episodes of hunter-gatherers during the past 45 *** studies reveal that relatively stable depositional conditions and a paleoenvironment characterized by a comparatively warm climate facilitated these multiple occupations at Nwya *** contemporaneous occurrence of the Upper Paleolithic blade technology on the Tibetan Plateau and most of Eurasia between 50 and 40 ka indicates rapid,large-scale dispersals of humans that profoundly affected human demography on a large *** new archaeological evidence and previously reported genetic data,we conclude that the Tibetan Plateau provided a relatively stable habitat for Upper Paleolithic hunter-gatherers,which may have contributed to the complex and multiple-origin gene pool of present-day Tibetans.

关键词： Tibetan Plateau Paleolithic Nwya Devu High-altitude adaptation Microblade industry Early Upper Paleolithic OSLdating AMS^(1.)C dating

Water and other volatiles on Mars

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National Science Review 2024年第06期11卷 12-14页

作者： Sen Hu Yubing Gao Zhan Zhou Liang Gao Yangting Lin Key Laboratory of the Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences

Mars, the intriguing red planet, is one of the planets most similar to the Earth in our solar system. It is widely accepted that Mars could have had a warm and wet climate in its early history supported by numerous lines of evidence, e.g. topography, canyons, outflow channels, presence of phyllosilicates and evaporative salts,sedimentary formation, and many others (e.g.[1.), and thus Mars is believed to once have a potentially habitable environment which could be able to supply fundamental conditions for the evolution of potential lives.

关键词： ISOTOPIC COMPOSITION MARTIAN ATMOSPHERE SUBSURFACE WATER ABUNDANCE TISSINT H2O CO2

An overview and perspective of identifying lunar craters

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Science China Earth Sciences 2024年第5期67卷 1395-1416页

作者： Yan JIANG Changyi Xu Ling CHEN State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100029China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100049China

The spatiotemporal evolution of lunar impact craters is crucial for investigating lunar interior structure,internal and external dynamic processes,and interplanetary impact *** in lunar crater identification are reviewed based on topography and gravity data,and the features and mechanisms of topographic or buried craters are analyzed regarding morphology,gravity anomalies,gravity gradients,and the underlying crust-mantle interface *** on the compiled crater catalog,the early lunar impact flux and thermal evolution are further discussed according to the basin ages and their interior *** some ancient impact basins,the crater size-frequency distribution measurements revealed age discrepancies from previous studies,suggesting that the lunar late heavy bombardment event started at~3.95 *** degraded bulge structures of the crust-mantle interface beneath mare basins reveal that these basins formed on the lunar crust surface under high-temperature conditions and underwent prolonged relaxation compared to highland ***,we reveal that the up-to-date identification of lunar buried craters remains inaccurate and incomplete,preventing us from accurately reconstructing lunar and interplanetary impact ***,we propose that a gravity model constructed using localized orthogonal basis functions can be useful for identifying lunar craters.

关键词： Moon Gravity field Craters Impact flux Early evolution

Morphology of crater and caldera lakes in the Far Eastern region of Russia and the features of their development

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Journal of Mountain Science 2024年第4期21卷 1246-1258页

作者： Dmitrii N.KOZLOV Ekaterina V.LEBEDEVA institute of Marine {1. and geophysics Far Eastern Branch of the Russian Academy of SciencesYuzhno-Sakhalinsk 693022Russia institute of Geography Russian Academy of SciencesMoscow 119017Russia

Volcanic lakes in the Kuril-Kamchatka region are difficult to access,and for this reason,they remain poorly studied,with only scattered and brief data *** authors have conducted a study of 1. lake basins using modern digital echolocation survey techniques and have also compiled and summarized published data for 1. lakes in the region,calculating their main morphometric *** has been established that many caldera lake basins are modified by young explosive funnels,extrusive or effusive domes,and exhibit traces of hydrothermal *** lakes of the same genetic type in the Kuril-Kamchatka region are similar in depth and depression forms,the group of caldera lakes shows less homogeneity across all morphometric *** was found that the absolute heights of the reservoirs on Kamchatka Peninsula are generally greater than those on the Kuril Islands,as is often the case with the size of their *** volcanic lakes under study can rapidly change their volume and shape under the influence of endogenous *** the first time for this region,on the base of repeated observations,underwater extrusive dome rate growth and the approximate rates of 2 lake level changes were *** observations of lakes in the Ksudach calderas(Kamchatka)and on Simushir Island indicate approximate rates of level changes:a decrease ranging within 0.5-0.6 m per year(over a 27-year observation interval)and an increase reaching up to 0.26 m per year(over a 48-year interval).The growth rate of the underwater extrusive dome in Lake Shtyubel has averaged 1.1.6 m per year over the past 25 *** analysis has facilitated the first generalization regarding the morphology and developmental features of crater and caldera lakes in the Kuril-Kamchatka region of Russia,representing an important step in their *** results obtained will provide a solid foundation for subsequent research in this region and may be of interest to researchers studying

关键词： Volcanic lakes Echolocation survey Volcanism Gashydrotherms Kamchatka Kuril Islands