Diagenetic traps in conglomerate in nearshore subaqueous fans in the steep slope zones of rift basins have been important exploration targets for subtle reservoirs in eastern China. However, the mechanism of how those...Diagenetic traps in conglomerate in nearshore subaqueous fans in the steep slope zones of rift basins have been important exploration targets for subtle reservoirs in eastern China. However, the mechanism of how those traps were formed is not clear, which inhibits further exploration for this type of reservoir. In order to solve the problem, we take as an example nearshore subaqueous fans in the upper part of the fourth member of the Shahejie Formation （Es4s） on the north slope of the Minfeng Subsag in the Dongying Sag. Combining different research methods, such as core observation, thin section examination, scanning electron microscope （SEM） observation, fluid-inclusion analysis, carbon and oxygen isotope analysis of carbonate cements, and analysis of core properties, we studied the genetic mechanisms of diagenetic traps on the basis of diagenetic environment evolution and diagenetic evolution sequence in different sub/micro-facies. Conglomerate in Es4s in the north Minfeng Subsag experienced several periods of transition between alkaline and acidic environments as ＂alkaline-acidic-alkaline-acidic-weak alkaline＂. As a result, dissolution and cementation are also very complex, and the sequence is ＂early pyrite cementation / siderite cementation / gypsum cementation / calcite and dolomite cementation- feldspar dissolution / quartz overgrowth quartz dissolution / ferroan calcite cementation / ankerite cementation / lime-mud matrix recrystallization / feldspar overgrowth carbonate dissolution / feldspar dissolution / quartz overgrowth / pyrite cementation＂. The difference in sedimentary characteristics between different sub/micro-facies of nearshore subaqueous fans controls diagenetic characteristics. Inner fan conglomerates mainly experienced compaction and lime-mud matrix recrystallization, with weak dissolution, which led to a reduction in the porosity and permeability crucial to reservoir formation. Lime-mud matrix recrystallization results in a rapid decrease in porosity and permeability in inne展开更多
This paper presents a bathymetry inversion method using single-frame fine-resolution optical remote sensing imagery based on ocean-wave refraction and shallow-water wave theory. First, the relationship among water dep...This paper presents a bathymetry inversion method using single-frame fine-resolution optical remote sensing imagery based on ocean-wave refraction and shallow-water wave theory. First, the relationship among water depth, wavelength and wave radian frequency in shallow water was deduced based on shallow-water wave theory. Considering the complex wave distribution in the optical remote sensing imagery, Fast Fourier Transform （FFT） and spatial profile measurements were applied for measuring the wavelengths. Then, the wave radian frequency was calculated by analyzing the long-distance fluctuation in the wavelength, which solved a key problem in obtaining the wave radian frequency in a single-frame image. A case study was conducted for Sanya Bay of Hainan Island, China. Single-flame fine-resolution optical remote sensing imagery from QuickBird satellite was used to invert the bathymetry without external input parameters. The result of the digital elevation model （DEM） was evaluated against a sea chart with a scale of 1：25 000. The root-mean-square error of the inverted bathymetry was 1.07 m, and the relative error was 16.2%. Therefore, the proposed method has the advantages including no requirement for true depths and environmental parameters, and is feasible for mapping the bathymetry of shallow coastal water.展开更多
The ecosystem-based management of nearshore waters requires integrated assessment of ocean health and scientific guidance on artificial regulations to promote sustainable development. Quantitative approaches were deve...The ecosystem-based management of nearshore waters requires integrated assessment of ocean health and scientific guidance on artificial regulations to promote sustainable development. Quantitative approaches were developed in this paper to assess present and near-term ocean health based on ecosystem services. Results of the case study in the Laizhou Bay of China showed that the index score of ocean health was 0.785 6 out of 1.0 at present and was expected to range from 0.555 1 to 0.804 1 in the near-term future depending on different intensities of artificial regulation of negative pressures. Specifically, the results of ocean health at present mainly indicated that cultural services and provisioning services performed essentially perfectly while supporting services and regulating services functioned less well. It can be concluded that this nearshore ecosystem would partially lose supporting and regulating services in the near-term future if the increasing pressures were not wellregulated but that all of these categories of ecosystem services could be slightly improved if the negative pressures were fully controlled. Additionally, it is recommended that publicity and education on ecosystem services especially on cultural services and regulating services should be further strengthened. The analytical process and resulting quantification provide flexible tools to guide future development of regulations so as to facilitate ecosystem-based management in the coastal zone.展开更多
基金co-funded by the National Natural Science Foundation of China (41102058)the National Science and Technology Special Grant (2011ZX05006-003)the Fundamental Research Funds for the Central Universities (12CX04001A)
文摘Diagenetic traps in conglomerate in nearshore subaqueous fans in the steep slope zones of rift basins have been important exploration targets for subtle reservoirs in eastern China. However, the mechanism of how those traps were formed is not clear, which inhibits further exploration for this type of reservoir. In order to solve the problem, we take as an example nearshore subaqueous fans in the upper part of the fourth member of the Shahejie Formation （Es4s） on the north slope of the Minfeng Subsag in the Dongying Sag. Combining different research methods, such as core observation, thin section examination, scanning electron microscope （SEM） observation, fluid-inclusion analysis, carbon and oxygen isotope analysis of carbonate cements, and analysis of core properties, we studied the genetic mechanisms of diagenetic traps on the basis of diagenetic environment evolution and diagenetic evolution sequence in different sub/micro-facies. Conglomerate in Es4s in the north Minfeng Subsag experienced several periods of transition between alkaline and acidic environments as ＂alkaline-acidic-alkaline-acidic-weak alkaline＂. As a result, dissolution and cementation are also very complex, and the sequence is ＂early pyrite cementation / siderite cementation / gypsum cementation / calcite and dolomite cementation- feldspar dissolution / quartz overgrowth quartz dissolution / ferroan calcite cementation / ankerite cementation / lime-mud matrix recrystallization / feldspar overgrowth carbonate dissolution / feldspar dissolution / quartz overgrowth / pyrite cementation＂. The difference in sedimentary characteristics between different sub/micro-facies of nearshore subaqueous fans controls diagenetic characteristics. Inner fan conglomerates mainly experienced compaction and lime-mud matrix recrystallization, with weak dissolution, which led to a reduction in the porosity and permeability crucial to reservoir formation. Lime-mud matrix recrystallization results in a rapid decrease in porosity and permeability in inne
基金The Public Science and Technology Research Fund Project of Ocean under contract No.201105001the National Nature Science Foundation of China under contract No.41576174the Public Science and Technology Research Fund Project of Surveying,Mapping and Geoinformation under contract No.201512030
文摘This paper presents a bathymetry inversion method using single-frame fine-resolution optical remote sensing imagery based on ocean-wave refraction and shallow-water wave theory. First, the relationship among water depth, wavelength and wave radian frequency in shallow water was deduced based on shallow-water wave theory. Considering the complex wave distribution in the optical remote sensing imagery, Fast Fourier Transform （FFT） and spatial profile measurements were applied for measuring the wavelengths. Then, the wave radian frequency was calculated by analyzing the long-distance fluctuation in the wavelength, which solved a key problem in obtaining the wave radian frequency in a single-frame image. A case study was conducted for Sanya Bay of Hainan Island, China. Single-flame fine-resolution optical remote sensing imagery from QuickBird satellite was used to invert the bathymetry without external input parameters. The result of the digital elevation model （DEM） was evaluated against a sea chart with a scale of 1：25 000. The root-mean-square error of the inverted bathymetry was 1.07 m, and the relative error was 16.2%. Therefore, the proposed method has the advantages including no requirement for true depths and environmental parameters, and is feasible for mapping the bathymetry of shallow coastal water.
基金The Public Science and Technology Research Funds Projects of Ocean in China under contract Nos 201005008 and201005009the National Natural Science Foundation of China under contract No.41206112
文摘The ecosystem-based management of nearshore waters requires integrated assessment of ocean health and scientific guidance on artificial regulations to promote sustainable development. Quantitative approaches were developed in this paper to assess present and near-term ocean health based on ecosystem services. Results of the case study in the Laizhou Bay of China showed that the index score of ocean health was 0.785 6 out of 1.0 at present and was expected to range from 0.555 1 to 0.804 1 in the near-term future depending on different intensities of artificial regulation of negative pressures. Specifically, the results of ocean health at present mainly indicated that cultural services and provisioning services performed essentially perfectly while supporting services and regulating services functioned less well. It can be concluded that this nearshore ecosystem would partially lose supporting and regulating services in the near-term future if the increasing pressures were not wellregulated but that all of these categories of ecosystem services could be slightly improved if the negative pressures were fully controlled. Additionally, it is recommended that publicity and education on ecosystem services especially on cultural services and regulating services should be further strengthened. The analytical process and resulting quantification provide flexible tools to guide future development of regulations so as to facilitate ecosystem-based management in the coastal zone.
