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71.
72.
沉积和成岩是碎屑岩储层物性的2个主控因素。沉积物粒度、结构、沉积相及搬运介质的流态制约着储层原生孔隙的发育,并影响着后续成岩作用的路径。然而,由于沉积之后长期的成岩作用影响,沉积对储层物性控制的定量表征难以实施。为此,提出了将物性数据校正至相同成岩作用水平--成岩作用拉平处理的思路。通过对珠江口盆地白云凹陷32口钻井分析化验资料的研究,分析了孔隙度、渗透率交会图及其随埋深的变化规律,识别了异常热演化、浅层钙质胶结和深部次生溶蚀等局部异常成岩作用,剔除了受影响的样品数据。根据拟合地温、埋深与物性的相关性,校正了区域差异成岩的影响,并在此基础上开展了沉积作用对储层物性的控制分析。分析结果表明,储层物性与沉积物粒度和分选性呈正相关,与成分成熟度无关,最有利的储层沉积微相为三角洲前缘水下分流河道和深水扇重力流水道。开展沉积作用对储层物性控制的定量化分析,并形成了完整的控制分析流程,对其他地区的类似研究具有一定借鉴意义。 相似文献
73.
S. Omodeo‐Sal R. Ondrak J. Arribas R. Mas J. Guimer L. Martínez 《Journal of Petroleum Geology》2019,42(2):145-171
The Mesozoic Cameros Basin, northern Spain, was inverted during the Cenozoic Alpine orogeny when the Tithonian – Upper Cretaceous sedimentary fill was uplifted and partially eroded. Tar sandstones outcropping in the southern part of the basin and pyrobitumen particles trapped in potential source rocks suggest that hydrocarbons have been generated in the basin and subsequently migrated. However, no economic accumulations of oil or gas have yet been found. This study reconstructs the evolution of possible petroleum systems in the basin from initial extension through to the inversion phase, and is based on structural, stratigraphic and sedimentological data integrated with petrographic and geochemical observations. Petroleum systems modelling was used to investigate the timing of source rock maturation and hydrocarbon generation, and to reconstruct possible hydrocarbon migration pathways and accumulations. In the northern part of the basin, modelling results indicate that the generation of hydrocarbons began in the Early Berriasian and reached a peak in the Late Barremian – Early Albian. The absence of traps during peak generation prevented the formation of significant hydrocarbon accumulations. Some accumulations formed after the deposition of post‐extensional units (Late Cretaceous in age) which acted as seals. However, during subsequent inversion, these reservoir units were uplifted and eroded. In the southern sector of the basin, hydrocarbon generation did not begin until the Late Cretaceous due to the lower rates of subsidence and burial, and migration and accumulation may have taken place until the initial phases of inversion. Sandstones impregnated with bitumen (tar sandstones) observed at the present day in the crests of surface anticlines in the south of the basin are interpreted to represent the relics of these palaeo‐accumulations. Despite a number of uncertainties which are inherent to modelling the petroleum systems evolution of an inverted and overmature basin, this study demonstrates the importance of integrating multidisciplinary and multi‐scale data to the resource assessment of a complex fold‐and‐thrust belt. 相似文献
74.
J. F. Rauball R. F. Sachsenhofer A. Bechtel S. Coric R. Gratzer 《Journal of Petroleum Geology》2019,42(4):393-415
This study investigates the hydrocarbon potential of Oligocene–Miocene shales in the Menilite Formation, the main source rock in the Ukrainian Carpathians. The study is based on the analysis of 233 samples collected from outcrops along the Chechva River in western Ukraine in order to analyse bulk parameters (TOC, Rock‐Eval), biomarkers and maceral composition. In Ukraine, the Menilite Formation is conventionally divided into Lower (Lower Oligocene), Middle (Upper Oligocene) and Upper (Lower Miocene) Members. The Early Oligocene and Early Miocene ages of the lower and upper members are confirmed by new nannoplankton data. The Lower Menilite Member is approximately 330 m thick in the study area and contains numerous chert beds and turbidite sandstones in its lower part together with organic‐rich black shales. The shales have a high content of silica which was probably derived from siliceous micro‐organisms. The TOC content of the shales frequently exceeds 20 wt.% and averages 9.76 wt.%. HI values range between 600 and 300 mgHC/gTOC (max. 800 mgHC/gTOC). The Middle Member contains thin black shale intervals but was not studied in detail. The Upper Member is about 1300 m thick in the study area and is composed mainly of organic‐rich shales. Chert layers are present near the base of the Member, and a prominent tuff horizon in the upper part represents a volcanic phase during shale deposition. The member grades into overlying molasse sediments. The average TOC content of the Upper Menilite succession is 5.17 wt.% but exceeds 20 wt.% near its base. Low Tmax and vitrinite reflectance measurements for the Lower (419°C and 0.24–0.34 %Rr, respectively) and Upper (425°C and 0.26–0.32 %Rr, respectively) Menilite Member successions indicate thermal immaturity. Biomarker and maceral data suggest a dominantly marine (Type II) organic matter input mixed with varying amounts of land‐plant derived material, and indicate varying redox and salinity conditions during deposition. Determination of the Source Potential Index (SPI) shows that the Menilite Formation in the study area has the potential to generate up to 74.5 tons of hydrocarbons per m2. The Chechva River outcrops therefore appear to have a significantly higher generation potential than other source rocks in the Paratethys realm. These very high SPI values for the Menilite Formation may explain why a relatively small area in Ukraine hosts about 70% of the known hydrocarbon reserves in the northern and eastern Carpathian fold‐thrust belt. 相似文献
75.
In the Kumano forearc basin, offshore SW Japan, the potential occurrence of hydrocarbons has been inferred from both geophysical surveys which point to the presence of natural gas hydrates, and geochemical analyses of gas samples recovered from boreholes and submarine mud volcanoes. The forearc basin is located in the inner part of the Nankai Trough where the Philippine Sea plate is subducting northwards beneath SW Japan. The basin succession unconformably overlies a deformed accretionary prism complex. Hydrocarbons with both microbial and thermogenic origins have been recorded in the Kumano Basin, but the thermogenic petroleum potential is poorly constrained because the regional‐scale geological architecture of the Nankai subduction zone is not well understood. In this paper, the regional‐scale petroleum potential of the Nankai Trough is investigated based on the geological interpretation of new seismic reflection images. The images were derived from legacy seismic survey data using advanced processing techniques such as reverse time migration, which make use of both primary and multiple reflections in wide‐angle seismic data collected with ocean‐bottom seismographs. In the study area, a seaward‐dipping reflector was identified which terminates at the plate boundary décollement and which is interpreted as part of the boundary between previously‐identified older (>14 Ma) and younger (<6 Ma) accretionary prisms. A triangle body at the base of the younger accretionary prism is interpreted to consist of underthrusted sediments including thick hemipelagic mudstones with source rock potential which were scraped off the down‐going oceanic plate. These tentatively identified, deeply‐buried mudstones may have the potential to generate thermogenic hydrocarbons which may then migrate upwards along dipping carrier beds or faults and fractures to the unconformity at the base of the Kumano forearc basin succession. The presence of hydrocarbons in the accretionary prism may be inferred from positive amplitude anomalies which have been identified in the reprocessed multi‐channel seismic data. The new reflection interpretations therefore allow the potential for thermogenic petroleum to be proposed in the study area. The hydrocarbon potential at this subduction margin may therefore rely not only on shallow microbial methane, but may also involve deeper, thermogenic petroleum generated within the underlying accretionary prism. 相似文献
76.
海堤外滩地种树效果及对行洪影响 总被引:11,自引:0,他引:11
本文在野外调查的基础上,以新会和斗门两地堤外滩地种植适生防浪树为例,介绍了珠江三角洲河口区堤外滩地种植适生防浪树的实践与经验,及其固滩固岸,防浪护堤的作用和效果。对三角洲不同水文区的河道滩槽宽度比进行统计分析,据不同水文区受灾的主要矛盾,指出滩地种树的利和弊及其对行洪的影响。 相似文献
77.
在河流污染物中,致癌物、致突变物、致畸形物(简称“三致”物)毒性最强,对人体健康威胁最大,据检测,在黄河干流兰州段,包头段和郑州段等河段已存在一定程度的“三致”物污染,就尽早开展饮用水水源地“三致”毒物污染监测,根据沿黄城市的分布情况及河段污染特点,可在兰州市包兰桥断面,包头市镫口断面、郑州市花园断面及河口段利津断面首先开展监测工作。 相似文献
78.
Deshan Tang 《Water Resources Management》1995,9(1):39-51
The major purpose of this paper is to present the useful techniques in the optimal allocation of water resources (OAWR) and to demonstrate using water resources applications how these methods can be conveniently employed in practice for systematically studying both simple and complex water resources problems. Formal modelling techniques in multiobjective decision-making provide many benefits to professionals working in water resources and elsewhere. A new Large-system Hierarchical Dynamic Programming (LHDP) method to solve the model can be carried out to ascertain the consequences of meaningful parameter changes upon the optimal or compromise solution.As a case study, the techniques and methods are applied to the OAWR of the Yellow River Basin (YRB) of China. The next paper shares with the reader recent research results on the OAWRYRB.Notation
L
i
inflows from the trunk stream in the subregioni.
-
S
i
run-off volume of the river sectioni.
-
Q
i
net inflows of intervals in the subregioni.
-
W
i
volumes of water drawn the trunk stream ofi into subdistricti.
-
H
i
volumes of water returning to the trunk stream in the subdistricti.
-
B
i(W
i)
the maximum net benefits (in hundred million yuan) from the annual-water consumption ofW
iin subregioni.
-
W
ik
the annual-water consumption (in hundred million m3) of sectorK in subregioni, k = 1, 2, 3, 4.
-
B
ik(W
ik
the maximum net benefits (in hundred million yuan) from the annual consumptionW
ikof sectork in subregioni.
-
BS
i(S
i)
the maximum net benefits (in hundred million yuan) obtained from the optimal allocation of the run-off volumeS
iof river trunki among different sectors within the months of a year. 相似文献
79.
为进一步掌握中国石油和天然气探明地质储量增长趋势,分析了2010—2019年中国新增石油和天然气探明地质储量分布和变化特征。结果表明:2010—2019年,中国新增石油探明地质储量主要分布在鄂尔多斯盆地、渤海湾盆地、准噶尔盆地等地区,以中浅层—中深层为主;新增天然气探明地质储量主要分布在鄂尔多斯盆地、四川盆地、塔里木盆地、东海陆架盆地等地区,以中深层—超深层为主。石油和天然气储量品质变差,丰度变低,埋深变大。中国新增油气探明储量的增长,主要集中在岩性地层油气藏、非常规油气藏、深层油气藏等领域。 相似文献
80.
为进一步掌握中国石油和天然气探明地质储量增长趋势,分析了2010—2019年中国新增石油和天然气探明地质储量分布和变化特征。结果表明:2010—2019年,中国新增石油探明地质储量主要分布在鄂尔多斯盆地、渤海湾盆地、准噶尔盆地等地区,以中浅层—中深层为主;新增天然气探明地质储量主要分布在鄂尔多斯盆地、四川盆地、塔里木盆地、东海陆架盆地等地区,以中深层—超深层为主。石油和天然气储量品质变差,丰度变低,埋深变大。中国新增油气探明储量的增长,主要集中在岩性地层油气藏、非常规油气藏、深层油气藏等领域。 相似文献