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

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 geology 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 10 lake basins using modern digital echolocation survey techniques and have also compiled and summarized published data for 15 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 dept. 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

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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

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Key issues on magnetic reconnection at Mercury

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Earth and Planetary Physics 2024年第5期8卷 673-685页

作者： Jun Zhong Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences

Magnetic reconnection processes and their impact on planetary magnetospheric dynamics exhibit significant differences due to differences in upstream solar wind conditions and internal planetary environments. Current understanding of reconnection phenomena at Mercury is rooted in the MESSENGER mission. However, direct detection of reconnection remains rare. Here, we aim to assess the limitations of MESSENGER in detecting reconnection in Mercury's space and to discuss key issues of reconnection that will be addressed by BepiColombo, including the dynamics of magnetic flux ropes, particle acceleration, density asymmetric reconnection,IMF-driven near-tail structures, and potential modes of magnetospheric convection.

关键词： magnetic reconnection Mercury MESSENGER BepiColombo

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Facies development and sedimentology of the Middle Miocene carbonates of the Raghama Formation, northeastern Saudi Arabia

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Acta Geochimica 2024年第1期43卷 87-96页

作者： Mansour H.Al-Hashim Abdelbaset S.El-Sorogy Meshal Wadani Department of geology and geophysics College of ScienceKing Saud University2455Riyadh 11451Saudi Arabia

Ragahama Formation comprises a siliciclastic continental deposits followed by marine carbonates, representing prograding alluvial fans from adjacent high hinterlands seaward into lagoons and fringing reef environments. The present work aimed to document the facies development and sedimentology of the Raghama carbonates exposed along the eastern coastal plain of the Red Sea, northwestern Saudi Arabia. Four stratigraphic sections were measured and sampled(D1–D4) and thin sections and major and trace element analyses were prepared and applied for petrographic and geochemical approaches. The carbonates were subdivided into three successive fore-reef, reef-core, and back-reef depositional facies. Sandy stromatolitic boundstone, microbial laminites, dolomitic ooidal grainstone, bioclastic coralline algal wackestone, sandy bioclastic wackestone, and coral boundstones were the reported microfacies types. Petrographic analysis reveals that the studied carbonates were affected by dissolution, dolomitization, and aggrading recrystallization, which affects both the original micrite matrix and grains or acts as fracture and veinlet filling leading to widespread vuggy and moldic porosity. No evidence of physical compaction, suggesting rapid lithification and recrystallization during early diagenesis and prior to substantial burial and intensive flushing by meteoric waters. Most of the original microstructure of corals were leached and destructed. This is indicated by the higher depletion in Sr and Ca levels and increase in Mg,Na, Fe, and Mn levels, especially in section D1, in comparison with the worldwide carbonates.

关键词： Raghama Formation Miocene Diagenesis Geochemistry Saudi Arabia

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Utilization of Pyrrolic Compounds as Indicators of Secondary Migration for Woodford Oils in the Anadarko Basin, Oklahoma, USA

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Journal of Earth Science 2024年第5期35卷 1499-1512页

作者： Mu Liu R.Paul Philp Key Laboratory of Cenozoic geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences School of Geosciences University of Oklahoma

Migration pathways and distances of the oils in reservoir are thought to affect the distribution of pyrrolic compounds such as carbazole, its alkyl derivatives(alkylated carbazoles) and benzocarbazoles, although other factors, including maturity and depositional environments may also affect the distribution of these organic nitrogen compounds. In this study, 14 oil samples produced from conventional reservoirs in Pauls Valley, south Oklahoma were investigated using organic geochemical techniques. The sterane and hopane fingerprints suggest that most of the oils were sourced from the Devonian Woodford shale. Maturity parameters consistently indicate that the maturity level of the studied samples are all of similar maturity(Rc = ～0.7%), suggesting the distribution of the organic nitrogen organic compounds is possibly reflecting variations in relative migration distances. The distribution of alkylcarbazoles revealed a preferential enrichment during migration, with the nitrogen-shielded alkylcarbazole tending to be enriched relative to the nitrogen-semi-shielded alkylcarbozoles particularly in oils produced close to the Arbuckle uplift to the east. Correspondingly, another family of pyrrolic compounds, benzocarbazoles, whose distributions also indicated that the Pauls Valley Woodford oils came from deeper part of the Anadarko Basin as the benzo-[a]/([a]+[c])-carbazole ratios decrease eastwards. In more specific migration systems, although the pyrrolic compound indicators are potentially disturbed by the structural complexes, the general migration directions suggest that the studied oils in Pauls Valley Hunton uplift were sourced from the deep basin area, and migrate upwards in porous sediments due to the buoyancy. This study investigates the feasibility of using pyrrolic compounds to estimate relative migration distances and will aid in the interpretation of migration history by using the distribution of carbazole, alkylated carbazoles, benzocarbazoles isomers in the An

关键词： carbazole migration oil Oklahoma biomarker organic geochemistry

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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(<0.2 Hz)waveforms,indicating that the 3D models adequately resolve overall large-scale subsurface ***,the 3D synthetics show discrepancies in higher frequencies(0.05–0.3 Hz)and the performance of the 3D velocity models varies from region to region,suggesting that smaller scale heterogeneities are not well *** shallow velocity structures(<10 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

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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 10 km dept.) 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(dept.s 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 dept.s 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

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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 dept. 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

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Platform Evolution in an Oligo-Miocene Back-arc Basin:An Example from the Central Iran Basin

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 185-206页

作者： Masoud SHARIFI-YAZDI Amirhossein ENAYATI Jamal SALEHI AGHDAM Mohammad BAHREHVAR Seyed Mustafa REZAEI Department of geology Faculty of Earth SciencesGeography and AstronomyUniversity of Vienna1090 Vienna.Austria geology and geophysics Department Tehran Energy Consultants(TEC Co.)TehranIran School of geology College of ScienceUniversity of TehranTehranIran Department of geology Tarbiat Modares UniversityTehranIran

The Qom Formation is the most important hydrocarbon reservoir target in Central *** Qom platform developed in a back-arc basin during the Oligo-Miocene due to the closing of the Tethyan *** formation consists of a variety of carbonate and non-carbonate facies deposited on a platform ranging from supratidal to basin.A combination of tectonic and eustatic events led to some lateral and vertical facies variations in the study *** third-order depositional sequences and related surfaces were identified regarding vertical facies changes in the studied sections of this Oligo-Miocene *** to all results and data,this succession was initially deposited during the Chattian upon a distally steepened ramp of siliciclastic-carbonate composition,including the Bouma ***,from the late Chattian to the Aquitanian,the platform changed into a homoclinal carbonate ramp with a gentle *** respect to tectonic activity,this phase was a calm period during the deposition of the Qom ***,a drowned carbonate platform and a rimmed shelf emerged during the Burdigalian,terminated by the continental deposits of the Upper Red *** all geological characteristics,three main tectono-eustatic evolutionary phases have been recognized in the Qom back-arcbasin.

关键词： carbonate ramp depositional facies submarine fan eustasy basement faults back-arc basin

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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

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