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通过对塔里木盆地陆相烃源岩所作的详细有机岩石学研究,提出了适合该盆地的陆相烃源岩有机组分分类方案,并系统地阐述各有机组分的光性、成因及岩石学特性。 相似文献
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This paper is mainly concentrated on the geochemical characteristics and origin of gas of Kekeya field in the Tarim basin, NW China. This study shows that Permian mudstone is the main source rock of oil and gas. Based on the carbon isotopes of C1--C4, the carbon isotope of gas in Kekeya field is a little heavier than that in the typical marine-derived gas. The relationship between carbon isotopes of methane and ethane is coincident with Faber equation of gas derived from organic matter Ⅰ/Ⅱ. The majority of gas maturity is estimated, based on the formula, at 1.8%-2.2% besides K2 and K18 wells. In addition, the gas derived from 0.9%-1.2% Ro source rocks may also bemixture. ^40Ar/^36Ar and ^3He/^4He ratios from the gas samples also support the mixing process. Moreover, the gas in this region is mainly generated from more mature source rocks although the low mature gas exists. 相似文献
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对藏北长江源地区河谷地貌和新构造变形调查发现,该区具有平行式水系格局,河谷地貌以形态不同的窄谷和宽谷为特点,新近纪以来该区主要经历了早期挤压和晚期伸展构造演化过程,产生了褶皱-逆冲、走滑剪切、正断层和地堑构造3种构造变形样式。长江源区河谷地貌的形成演化明显受新构造运动的影响,新构造运动不仅控制了河谷地貌形态与水系格局,而且影响了河流阶地分布以及洪(冲)积扇的形态、结构。长江源地区主要水系至少自全新世以来是沿新构造运动产生的不同性质断裂构造溯源侵蚀发育而成。 相似文献
26.
主动电场探测技术依靠激励源发射电场信号,通过测量电位信号实现目标探测。根据当前主动电场探测掩埋目标研究进展,简要介绍了其原理,对国内外掩埋大目标领域的关键技术(海洋可控源电磁法) 的研究现状以及发展趋势进行了归纳整理;针对主动电场探测水下掩埋小目标的问题,详细介绍了国外实验、 先进设备的工作机理,总结了国内相关领域的研究;通过对水下电场传感器国内外研究现状的分析,指出国内在水下掩埋目标主动电场探测领域已有的基础。最终对该技术的发展及应用前景进行了展望。 相似文献
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利用2008年1月1日—2021年12月31日发生在蒙冀辽交界地区的472个地震的P波初动符号资料,应用综合震源机制解法获得了蒙冀辽交界地区0.25°×0.25°精细应力场,所得应力场结果基本覆盖整个蒙冀辽交界地区。应力场反演结果显示: ①蒙冀地区受拉张应力体系作用,主压应力场为东向,源自青藏高原东北边缘的强烈挤压作用。综合震源机制解类型主要为正断层和走滑型,P轴整体呈NE、NNE向,T轴整体呈NW或NNW方向,与前人研究该区域活动构造运动和地块受拉张和裂陷作用相符合。②蒙辽交界地区P波矛盾比较大,震源机制界面较为散乱,蒙辽或冀辽交界地区辽宁一侧震源机制解以逆断层为主,辽南地区震源机制以正断性质为主。 相似文献
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WANG Jin-liang CHEN Cheng-long NI Jiu-pai XIE De-ti GUO Xi LUO Zhi-jun ZHAO Yue 《山地科学学报》2019,16(9):2048-2062
Ascertaining the relationship between \"source-sink\" landscape and non-point source(NPS) pollution is crucial for reducing NPS pollution, however, it is not easy to realize this target on cell unit scale. To reveal the relationships between \"sourcesink\" landscape and NPS pollution based on cell units of a small catchment in the Three Gorges Reservoir Region(TGRR), the runoff and nutrient yields were simulated first by rainfall events on a cell unit scale based on the Annualized AGricultural Non-Point Source Pollution Model(AnnAGNPS). Landscape structure and pattern were quantified with \"sourcesink\" landscape indicators based on cell units including landscape area indices and locationweighted landscape indices. The results showed that:the study case of small Wangjiagou catchment highlighted a good prediction capability of runoff and nutrient export by the AnnAGNPS model. Throughout the catchment, the spatial distribution trends of four location-weighted landscape indices were similar to the trends of simulated total nitrogen(TN) and total phosphorus(TP), which highlighted the importance of spatial arrangement of \"source\" and \"sink\" landscape types in a catchment when estimating pollutant loads. Results by Pearson correlation analysis indicated that the location-weighted landscape index provided a more comprehensive account of multiple factors, and can better reflect NPS-related nutrient loss than other landscape indices applied in single-factor analysis. This study provides new findings for applying the \"source-sink\" landscape indices based on cell units in small catchments to explain the effect of \"source-sink\" landscape on nutrient export based on cell unit, and helps improve the understanding of the correlation between \"source-sink\" landscape and NPS pollution. 相似文献
30.
Stable oxygen and hydrogen isotopic compositions (δ18O and δD) of plant xylem water and its potential water sources can provide new information for studying water sources, competitive interactions and water use patterns of plants. The contributions of different water sources to three plants, Hedysarum scoparium (HS), Caragana Korshinskii (CK) and Artemisia ordosica(AO), were investigated in the artificial sand-fixed vegetation of Shapotou, the southeastern margin of the Tengger Desert of northwestern China, based on meteorological data and δ18O and δD values of precipitation, groundwater, soil water and xylem water of HS, CK and AO. Our results indicated that water content throughout the soil profile and their competition balance for water uptake during different growth season. The results indicate that these sand-fixed plants have developed into a relatively stable stage and they are able to regulate their water use behavior as a response to the environmental conditions, which reinforces the effectiveness of plantation of native shrubs without irrigation in degraded areas. 相似文献