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Development of engineering-geological parameters evaluation system for hydrate-bearing sediment and its functional verification
Engineering-geological parameters are crucial for evaluation of geohazard potential in marine hydrate exploitation. The combination of piezocone penetration and vane shear test may help gain longitudinally continuous and reliable parameters for hydrate reservoir, which has great perspective in integrated engineering and geological field survey. However, application of these techniques to marine hydrate survey has remained vacant so far. To better understand the penetration or shearing behaviors and their influencing factors in hydrate-bearing sediment (HBS), we developed a novel engineering-geological parameters evaluation system, which may satisfy the need of five-bridge piezocone penetration test and vane shear test. The tip resistance, side frictional resistance, excess pore pressure, electrical resistance, and video along the penetration path could be obtained through five-bridge piezocone penetration test. The method of electrical resistivity tomography is firstly combined with piezocone penetration and vane shear technology in this system to explain the relationships between engineering geological parameters and hydrate saturation. The sandy sediment and clayey-silt sediment (free of hydrate) are involved to verify the functions of the system. The results show favorable fitness with the field-obtained data. Repeated experiments show high reproducibility of the data. This system proved the possibility of establishing quantitative evaluation models of engineering geological parameters in HBS, and also provided a basic platform for novel probing device test in the integrative engineering-and-geological hydrate survey.
LI Yanlong, CHEN Qiang, LIU Changling, WU Nengyou, SUN Jianye, SHEN Zhicong, ZHANG Minsheng, HU Gaowei
doi: 10.16562/j.cnki.0256-1492.2019110401
Marine Geology & Quaternary Geology. 2020, 40(5): 192-200
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Characteristics, distribution and implication of hydrothermal minerals in Tianxiu Hydrothermal Field, Carlsberg Ridge, northwest Indian Ocean
Hydrothermal minerals could originate from mass wasting of hydrothermal deposits or from the hydrothermal plume falling-out. The types and their spatial distribution of hydrothermal minerals are important indicators for constraining the location of hydrothermal field. The Tianxiu Hydrothermal Field (3°41′N,63°50′E) is an ultramafic-hosted field located on the Carlsberg Ridge, northwest Indian Ocean. In this paper, surface sediments collected from 4 stations near the active venting site of Tianxiu Hydrothermal Field and its surrounding regions were studied on hydrothermal minerals to understand their spatial variations on morphology, composition, abundance and particle size. Near the venting site (0 ~ 0.22 km) the hydrothermal minerals are dominated by Cu-Zn-Fe containing sulfide aggregates, in the size from gravel to sand, originated from the mass wasting of the sulfide deposits and precipitation from the hydrothermal fluid. For samples collected outside of the hydrothermal field (1.84 ~ 6.05 km away), the hydrothermal minerals are dominated by fine grain hydrothermal oxides and hydroxides derived from plume fallout. Our results suggest that the types and grain size of hydrothermal minerals and their spatial distribution can be served as a good indicator for tracking unknown active and inactive hydrothermal field and prospecting of the associated hydrothermal sulfide resources.
CAI Yiyang, HAN Xiqiu, QIU Zhongyan, WANG Yejian, LI Mou, Samuel Olatunde Popoola
doi: 10.16562/j.cnki.0256-1492.2019101201
Marine Geology & Quaternary Geology. 2020, 40(5): 36-45
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Research progress in seamount influence on depositional processes and evolution of deep-water bottom currents
Seamount is a kind of tectonic geomorphological features widely distributed in the deep sea around the world, where bottom currents persistently exist, thus the interactions between seamounts and bottom currents are very common and will bring about non-negligible influence on deep-water sedimentation and their evolution. This study summarized the global researches on the deep water sedimentation by bottom currents around seamounts, suggesting that deep-water bottom-current hydrodynamics would change under the direct or indirect influence of seamounts, including the changing in flow paths, generation of secondary bottom currents, and variation in ecosystems. Consequently, deep-water sedimentary morphologies and lithofacies would display special distribution patterns. With the evolution of bottom-current hydrodynamics and sedimentary morphologies, deep water sedimentation processes and associated responses would change as well. In summary, bottom currents are complex and special around seamounts, resulting in sedimentary morphologies and lithofacies features as well as distribution patterns differing from those on the open slope. Thus, the sedimentary morphologies and lithofacies formed under bottom currents around seamounts have very particular implications for basin structures and palaeoceanography evolution. However, there is still lack of study concerning the coupling relationship between seamounts and deep water sedimentation processes, greatly limiting deep-sea resource exploration and geo-hazard study, thus more attention is required to be paid to the relationships in the future research of deep-water sedimentology.
WANG Xingxing, CAI Feng, WU Nengyou, LI Qing, SUN Zhilei, WU Linqiang
doi: 10.16562/j.cnki.0256-1492.2019111101
Marine Geology & Quaternary Geology. 2020, 40(5): 68-78
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Stratigraphic features and controlling factors in the eastern Sub-basin of the Central Basin, South China Sea during the post-spreading period
Driven by sea-floor spreading, the tectonic evolution of a marginal basin could be divided into three stages, namely the pre-spreading, spreading and post-spreading stages. Most of the thick deposits developed in the Central basin of the South China Sea, especially the thickest in the eastern Sub-basin was deposited in the post-spreading stage. Various factors were active in different parts of the eastern Sub-basin, resulting in a great variety of post-spreading stratigraphic features. A great amount of information about the formation and evolution of the South China Sea was preserved in the thick sediments. Therefore, it is important to study the stratigraphic features in the eastern Sub-basin formed during the post-spreading stage. According to the age data from some ODP and IODP drilling holes, the synthetic seismic records passing through the wells were calibrated and then the sequence stratigraphy of the region was established and dated. Upon the basis, we discussed in this paper the characteristics of the strata and related factors. The result shows that deposition of the sediments with stable thickness was mainly caused by stable basement subsidence with substantial terrigenous sediments input from the north, and the micro-plate subducting toward Manila trench was the main influence factor which gave rise to the characters of the strata in different age in the east. The sediments containing certain amount of volcanic debris was deposited in the west and middle part owing to the frequent magmatic activities. And in the south of the basin, turbidite sediment waves occurred due to the control of slope environment.
QIU Yan, DU Wenbo, HUANG Wenkai, WANG Yingmin, NIE Xin
doi: 10.16562/j.cnki.0256-1492.2020053001
Marine Geology & Quaternary Geology. 2020, 40(5): 1-14
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Collision of North China and Yangtze Plates: Evidence from the South Yellow Sea
As an important geological event in East China, the collision of the Yangtze plate and North China plate gave rise to the formation of the Sulu-Dabie orogen. This paper made a thorough review on the different collision models. Data from seismic profiles and seismic tomography support the detachment model to the Lower Yangtze region. It says that the upper crust of the Yangtze Block detached from the lower crust, just like a crocodile opened its mouth, and the North China plate fortunately wedged into it. In the Qianliyan belt there developed similar gravity and magnetic anomalies with Sulu orogen, as the extension of the Dabie-Sulu orogen. In seismic profiles, the South Yellow Sea Basin and Qianliyan Uplift Belt are different in reflection characteristics. There are complete stratigraphic reflections in the basin but no obvious reflections in the uplift. All the boundaries show a south-dipping reflection patterns, suggesting the obduction of the Yangtze Block. The collision and derived compression mainly happened in Triassic while the growth strata deformation formed in lower Jurassic. In the lower crust of the Qianliyan Uplift, the Moho reflection is recognized at ~10 s, and disappeared below the South Yellow Sea Basin. It is thus speculated that the lower crust under the Qianliyan Uplift belong to the North China Plate, and the collision between Yangtze and North China caused the fading out of the Moho reflection. Generally, the geophysical data from the South Yellow Sea support the hypothesis that the North China Block wedged into the crocodile mouth of the Yangtze Block.
CHEN Jianwen, XU Ming, LEI Baohua, SHI Jian, LIU Jun
doi: 10.16562/j.cnki.0256-1492.2019070902
Marine Geology & Quaternary Geology. 2020, 40(3): 1-12
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Meso−Cenozoic deformation and dynamic mechanism of the ocean−continent transitional zone in the East China Sea
Continent-ocean transition zone (COT) is a key to better understanding the geodynamic process and its mechanism between ocean and continent and has long been one of the hot issues in geoscientific research. The Southern East China Sea Shelf Basin (SECSSB), Zhejiang, Fujian and Guangdong regions, located at the eastern South China Block, have suffered from the westward subduction of the Izanagi Plate and the Pacific Plate as well as the far-field effect of the collision of the Indian Plate and the Eurasian Plate since Mesozoic, and complete records on tectonic deformation and COT interaction in this period are preserved. Based on geological and geophysical data acquired over the last 10 years, synthesizing Meso-Cenozoic research results and making land-ocean correlation, this paper studied the Meso-Cenozoic tectonic deformation and dynamic mechanism of the SECSSB and its adjacent areas. Based on the field geological survey, this paper provides a summary of the Meso-Cenozoic tectonic deformation in the land area. 4 major regional unconformities and 4 main structural layers are recognized, in addition to the 6 tectomagmatic periods and 5 large regional faults which have great influence on the Meso- Cenozoic sedimentary evolution. Meanwhile, this paper also summarized the Meso- Cenozoic stratigraphic framework and recognized 5 types of tectonic styles and 12 tectonic combinations in the SECSSB. Faults mainly trend in NE−NNE except a few small ones trending in EW. Magmatic rocks were mainly formed during the Yanshanian and Himalayan periods and display a spatially regular migration from west to east. Numerical simulation results show that slow-stretching model is consistent with the Mesozoic tectonic setting and local water-bearing mantle melting of the region since plate subduction is believed the main reason for the formation of magmatic rocks in the study area. Based on the study mentioned above, we discussed in details the Meso-Cenozoic tectonic evolution and basin type in this paper.
YANG Chuansheng, YANG Changqing, YANG Yanqiu, SUN Jing, YAN Zhonghui, WANG Jianqiang
doi: 10.16562/j.cnki.0256-1492.2019080201
Marine Geology & Quaternary Geology. 2020, 40(1): 71-84
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Second-order climatic cycles in the Chinese Loess Plateau and their bearing on precession driving
Sub-palaeosols are commonly observed in the Chinese Loess Plateau (CLP). Based on the grain size and magnetic susceptibility data, second-order climatic stages (SOCC) of the CLP are further divided and correlated, and the sequence of SOCC after L21 is preliminarily established in this paper. Taking the Northern Hemisphere summer solstice at perihelion and apohelion as boundaries, precession cycles are transformed into the “Ideal precession climatic cycle” (IPCC) for the Northern Hemisphere. Correlated with the SOCC established in the Loess Plateau, it is found that there are 122 second order climatic stages, corresponding to 61 secondary climatic cycles, could be identified in the 72 precession cycles since L21. Except for the stages which are too weak in precession variation, there is almost a one-to-one correspondent relationship between the SOCC and the IPCC. It is, therefore, concluded that the SOCC in the CLP are mainly driven by precession cycles. Compared with the first-order climatic cycle which reflect global climatic change, the SOCC of the CLP highlights the role of the precession cycle with hemispheric effect in the climatic change of the Loess Plateau. The SOCC have been partly obscured by the glacial-interglacial cycles. It is needed to trace back and forth across the plateau to reveal the pattern clearly. SOCC in the CLP not only serves as the basic unit for stratigraphic classification, but also has some absolute chronological significance to some extent due to the constraints of precession. Enough attention should be paid to its paleoclimatic implication in addition to stratigraphic significance.
ZHAO Qiang, LI Xishuang, WU Yonghua, LIU Jianxing
doi: 10.16562/j.cnki.0256-1492.2018110501
Marine Geology & Quaternary Geology. 2020, 40(1): 136-159
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A comparative study on the Late Quaternary stratigraphic architecture and formation of megadeltas in East and South Asia
Based on the researches on the evolution of megadeltas in East and South Asia since last deglaciation, we carried out a comparative study on the Late Quaternary stratigraphic architecture, sedimentary systems and the initiation time of megadeltas at large river mouths of the region. Major control factors on deltaic evolution are revealed and discussed. Our data suggests that all the river mouths in the region seem having experienced similar evolutionary history, including the infilling of incised palaeo-valleys and estuaries in Early Holocene, and deltaic progradation in Middle to Late Holocene, controlled by the sea-level change. However, there are some differences in the stratigraphic architecture and sedimentary history from river to river. The most remarkable difference is the time of delta initiation, which is related to the geomorphology and geology of the drainage basin and the sedimentary basin at river mouths. Those rivers having short flow paths and erosive bedrocks in the drainage basin, such as the Ganges-Brahmaputra, usually produce a huge amount of sediment load. As a result, the time of the delta initiation was obviously earlier than other rivers. The Pearl River delta is another example. It has a semi-closed shallow sedimentary basin which is beneficial to the formation of delta in the Middle Holocene.
PAN Dadong, WANG Zhanghua
doi: 10.16562/j.cnki.0256-1492.2019012901
Marine Geology & Quaternary Geology. 2020, 40(1): 12-21
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Depositional pattern and exploration prospect of the deepwater sediments in Shuangfeng basin
The South China Sea is an important region offshore China for exploration of oil and gas resources and gas hydrate. As the exploration in the shallow waters is moving into a mature stage, the deep water area in the northern part of the South China Sea has gradually become a research hotspot. The study of the Shuangfeng Basin in the deep water basins of the northern South China Sea is obviously lagged behind the others. In this paper, seismic geophysical exploration theories and analogy methods are applied to study the tectono-sedimentary pattern and oil and gas exploration prospects of the basin, based on the 2D multi-channel seismic data and the drilling data of the basin and surrounding areas. A large amount of seismic data were processed and analyzed, and seven reflection horizons traceable recognized in the Shuangfeng basin. Three sets of the seismic sequence are established according to unconformable boundaries. Data shows that after mid-Late Miocene, the basin entered into a bathyal-pelagic depositional environment dominated by deep water sediments, such as undercut channel-fillings, deep water fans and slump deposits. The Cenozoic in the basin is quite thick. Analogy analysis of drilling data and basin modeling suggest that the Oligocene lacustrine-gulf facies in the western and northern depressions have reached the maturity or early maturity stage and had certain hydrocarbon generation capacity. The alluvial fan and fan deltaic deposits developed around the periphery, and the slope fan and the pelvic fan developed in the basin center could be good reservoirs. The bathyal mudstone deposited since Early Miocene are good in quality as regional cap rocks. Excellent source-reservoir-cap systems are available for oil and gas accumulation.
ZHANG Li, LEI Zhenyu, XU Hong, LUO Shuaibing, QIAN Xing, SHUAI Qingwei, JI Zhaopeng, ZHOU Jiawei
doi: 10.16562/j.cnki.0256-1492.2018091401
Marine Geology & Quaternary Geology. 2020, 40(1): 1-11
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Regional evaluation of oil and gas resources in offshore China and exploration of marine Paleo-Mesozoic oil and gas in the Yellow Sea and East China Sea
40 years have passed since the reestablishment of the Qingdao Institute of Marine Geology in 1979. In the past 40 years, following the basic objective to carry out public oil and gas surveys in China seas and global waters with the Yellow Sea and East China Sea as major targets so as to meet the increasing demand of energy resources of the nation and society, the institute has devoted a lot to the studies on hydrocarbon resource generation and distribution patterns in China seas, upon the international frontiers of marine science and technology. A great number of breakthroughs have been achieved, such as the discovery of new oil and gas horizons and districts. Under the guidance of national energy strategy and the task to make China a strong marine power, the Institute has persisted in regional evaluation of oil and gas resources in China seas, in particular in the Yellow Sea and East China Sea. The research can be roughly subdivided into three stages: the first stage focusing on comparison of offshore and neibouring basins; the second stage focusing on the study of regional evaluation strategies of China seas and the third stage focusing on new horizons and new districts in the Yellow Sea and East China Sea. A map series on distribution of sedimentary basins in China seas and a set of dynamic situation map of oil and gas exploration and development in China Sea were compared and published successively. During the period, following achievements are necessary to be mentioned: (1) Breakthroughs in early stage oil and gas evaluation technology and the deep seismic detection technology for offshore sedimentary basins; (2) Resource assessment in China seas. Data proves that China is rich in marine oil and gas. And the next cycle of survey and exploration should be placed in the new horizons, such as gas offshore, buried hills oil and gas resources in the hydrocarbon-rich sags, oil and gas in deepwaters, organic reefs in the South China Sea and unconventional gas; (3) Further understandings of basic geology, such as, basement properties, marine stratigraphic sequences, tectonic division, characteristics of Jurassic foreland basins, marine basin hydrocarbon geologic conditions and favorable zones in the South Yellow Sea basins; (4) Solution of some specific geological problems related to oil and gas accumulation. Such as, Mesozoic stratigraphic sequences, two-stage basin architecture, basin properties, Mesozoic stratigraphic distribution patterns and the discovery of " Great East China Sea”, Mesozoic hydrocarbon geologic conditions and favorable zones in the East China Sea; (5) Discovery of Paleozoic reservoirs. These achievements and discoveries have laid a solid foundation for the future oil and gas geological survey and exploration in China seas.
CHEN Jianwen, LIANG Jie, ZHANG Yinguo, YANG Changqing, YUAN Yong, XU Ming, WANG Jianqiang, LEI Baohua, LI Gan, YANG Yanqiu, YANG Chuansheng, SUN Jing
doi: 10.16562/j.cnki.0256-1492.2019112001
Marine Geology & Quaternary Geology. 2019, 39(6): 1-29
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Tectono-sedimentary evolution of the Mesozoic in the southern East China Sea Shelf Basin and its bearing on petroleum exploration
The East China Sea Shelf Basin is located on the southeastern margin of the Eurasian Plate. Since Mesozoic, the formation and evolution of the basin are characterized by multiphase oceanic subduction of the Paleo-Pacific plate and superimposition of multistage tectonic systems. As the results, many questions, such as prototype of the basin, tectono-sedimentary evolution and hydrocarbon accumulation, have always remained in puzzle. Based on the latest seismic surveys and the drilling data from adjacent land areas, this paper is devoted to the key problems and exploration directions of the Mesozoic hydrocarbon accumulations, through sea-land correlation, establishment of Mesozoic sequence stratigraphy and remodeling of tectono-sedimentary evolution process. It is found that there are two super-sequences and seven seismic sequences in the Mesozoic in the basin. It was a passive continental margin before Late Triassic, an active continental margin depression in Late Triassic-Middle Jurassic, but a faulted basin on an active continental margin in Cretaceous. It is proposed that the basement of the basin in early stage was in NE direction which controls the framework of the Mesozoic basin and macroscopic hydrocarbon-bearing properties. Corresponding to the two-stages of tectonics, there are two sets of Mesozoic source-reservoir-caprock combinations. The Keelung movement, Yushan movement and Yandang movement dominated the formation and accumulation of early-stage oil and gas, while the Longjing movement contributed to the reform of oil and gas reservoirs. Inherited uplifts (slope), such as the Minjiang slope and the " uplifts in depressions” in the Taipei transitional zone, are the main petroleum exploration targets in the future to come.
YANG Changqing, YANG Yanqiu, YANG Chuansheng, SUN Jing, WANG Jianqiang, XIAO Guolin, WANG Jiao, WANG Mingjian
doi: 10.16562/j.cnki.0256-1492.2019070305
Marine Geology & Quaternary Geology. 2019, 39(6): 30-40
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Seismic detection of deep structure for Southern Kyueshu-Palau Ridge and its possible implications for subduction initiation
The Kyushu-Palau Ridge (KPR) is an excellent place to study the initiation of plate subduction, and thus a unique natural laboratory for developing the plate tectonic theory. Based on a thorough review of literatures, we tried in this paper to reveal the solid vs. liquid structure of the lithosphere using the geophysical data by OBS and OBEM along a regional transection passing through the West Philippine Basin, the KPR, and the Perce-Vela basin. Combined with geochemical studies and computational geodynamic simulations, the characteristics of the deep subducted slabs, the different oceanic lithosphere, the corresponding magmatic activities and mechanism as well as the flux and cycling of the subducted materials are investigated. Upon the basis, a complete evolution model including subduction initiation, island arc splitting, and the back-arc seafloor spreading is proposed in this paper for the tectonic evolution of a subduction zone.
DING Weiwei, LI Jiabiao
doi: 10.16562/j.cnki.0256-1492.2019071601
Marine Geology & Quaternary Geology. 2019, 39(5): 98-103
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Interaction between seafloor cold seeps and adjacent hydrothermal activities in the Okinawa Trough
As the seafloor extreme environmental systems, both hydrothermal vents and cold seeps are the critical pathways between the lithosphere and exosphere (biosphere, hydrosphere and atmosphere) for transfer and exchange of materials and energies. There are significant differences, but also many similarities between the two systems. Recent investigations show that in some special tectonic units, hydrothermal vents and cold seeps are not isolated from each other, but instead there are some interactions or coupling relationships in terms of tectonic geology, biological ecology and element cyclicity. As a typical back-arc basin in the western Pacific Ocean, there are abundant hydrothermal vents and cold seeps developed in the Okinawa Trough (OT). Therefore, it has become an ideal natural laboratory for studying the two extreme environmental systems and their interactions. On the basis of literature researches and careful field case studies, we investigate the material diffusion process and biogeochemical process between cold seeps and hydrothermal vents adjacent to each other within the trough. A conceptual model is then established for the interactions between the fluids from the two extreme systems. Our results suggest that it would help to establish a more complete model of the coupling relationship between the two systems in the future, if the structural development characteristics, pore fluid evolution, biological communities, and mineral chemistry of the two deep-sea extreme environments are systematically analyzed. Moreover, it will help to reveal the interaction between them in biological ecology and finally establish a model of interaction between hydrothermal vents and cold seeps on the basin scale, so as to better understand the interaction process between cold seeps and hydrothermal systems and even the coupling of " flow-solid” in the Western Pacific Ocean or the whole Earth.
WU Nengyou, SUN Zhilei, LU Jianguo, CAI Feng, CAO Hong, GENG Wei, LUO Min, ZHANG Xilin, LI Qing, SHANG Luning, WANG Libo, ZHANG Xianrong, XU Cuiling, ZHAI Bin, LI Xin, GONG Jianming, HU Yu, LIN Genmei
doi: 10.16562/j.cnki.0256-1492.2019070102
Marine Geology & Quaternary Geology. 2019, 39(5): 23-35
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Study of the Caroline plate: Initial subduction, initial spreading and fluid-solid interaction
The western Pacific has the most active plate tectonic processes and land-ocean interactions. The Caroline Basin is a small plate formed between the Tethys and the Pacific, currently located at the throat of the Indonesian seaway, and takes a large area of the western Pacific warm pool. The Caroline plate is rather complex topographically and is characterized by ridges and relic spreading centers. The plate is bordered by young active subduction zones and active spreading centers, and strongly interacts with the surrounding Philippine Sea plate, the Pacific plate, the Ontong-Java large igneous province, and many deep trenches. Therefore, it is an ideal place for studying process and dynamics of initiation of subduction and seafloor spreading, as well as the interaction of the solid earth with seawater. In the past, the investigation of the Caroline Basin was done mostly in the 70—80 s of last century. So far, many controversies remain unsolved on the nature and genesis of some tectonic units, and the interactions among multiple geospheres were seldom explored. The implementation of the major research project on " Multi-sphere Interaction of the Western Pacific Earth System” supported by the National Natural Science Foundation of China greatly accelerate the pace of marine research in the Western Pacific region. In this project, we conduct comprehensive geophysical and geochemical analyses of the tectonic boundary process of the Caroline Basin and the extent of serpentinization of the uppermost lithospheric mantle in the basin. We also examine the coupling between the deep process in the lithosphere and the shallow process on the seabed, in particular the relationship between water and heat flux. Based upon the research, we propose in this paper an evolutional model for this unique oceanic micro-plate and its tectonic boundaries. Further research activities, including scientific ocean drilling, are recommended.
LI Chunfeng, LI Gang, LI Zilong, LIU Wenxiao, ZHANG Lulu, LU Zhezhe, CHEN Xuegang, YAO Zewei
doi: 10.16562/j.cnki.0256-1492.2019031501
Marine Geology & Quaternary Geology. 2019, 39(5): 87-97
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The sources of dissolved iron in the global ocean and isotopic tracing
Iron is an essential trace element to oceanic primary productivity, which may influence the structure of marine biological community, ecological function, and carbon cycle. It is therefore of great importance to understand the sources and supply of dissolved Fe to the ocean and its responses to the global climate change. Early studies often emphasize dust input as the mechanism to maintain oceanic Fe cycling. In recent years, with the increase in Fe data, especially along with the launch of GEOTRACES program, the important role of dissolved Fe released from continental shelf sediments and hydrothermal activities has been highlighted. Nevertheless, there still remain considerable uncertainties regarding the contribution of Fe to the open ocean from different sources. Our review begun with characterizing the chemical speciation of dissolved Fe, especially of organic ligand in oceanic Fe cycling, and then presented flux estimation of different Fe sources as well as the debates regarding the oceanic Fe fertilization during the time of Quaternary. Iron isotopes provide a new tool for studying the evolution of Fe sources. We have discussed the Fe isotope signatures of different sources, and proposed that the combination of isotopes and speciation analysis of sedimentary reactive Fe might provide a new perspective in understanding the mechanism of Fe export and transport from continental shelf, hydrothermal activity, and dust in the past.
CHEN Tianyu, CAI Pinghe, LI Weiqiang, YANG Tao, LING Hongfei, JI Junfeng
doi: 10.16562/j.cnki.0256-1492.2019070501
Marine Geology & Quaternary Geology. 2019, 39(5): 46-57
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