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971.
Geologic Characteristics of Volcanic Hydrocarbon Reservoirs and Exploration Directions in China 总被引:4,自引:0,他引:4
ZOU Caineng ZHU Rukai ZHAO Wenzhi JIA Chengzao ZHANG Guangy YUAN Xuanjun ZHAO Xia WEN Baihong 《《地质学报》英文版》2010,84(1):194-205
Abstract: Volcanic rocks are distributed widely in China, which are important exploration targets. By analyzing many discovered volcanic hydrocarbon reservoirs all over the world, the authors summarized the geologic characteristics of the formation of volcanic hydrocarbon reservoirs in China, and gave further exploration directions and advices. (1) There are mainly Carboniferous-Permian, Jurassic-Cretaceous, Paleogene-Neogene volcanic rocks in oil- and gas-bearing basins in China, which are mainly distributed in the Junggar Basin, Songliao Basin, Bohai Bay Basin, etc. There are mainly intermediate rocks and acidic rocks in east China, and intermediate rocks and basic rocks in west China. They primarily develop in intracontinental rift settings and island arc environments. (2) Pore-fissure reservoirs are distributed widely in basins, which are volcanic rocks mainly in explosive and effusive facies. (3) Volcanic hydrocarbon reservoirs are chiefly near-source lithostratigraphic hydrocarbon reservoirs, and the oil and gas accumulation is predominantly controlled by lithotypes, faults and structural positions. (4) Deep-seated oil and gas reservoirs in the Songliao Basin and Carboniferous volcanic hydrocarbon reservoirs in the Junggar Basin are potential giant volcanic gas provinces, the volcanic hydrocarbon reservoirs in the Bohai Bay Basin and Santanghu Basin are favorable for oil and gas reserves increase, and volcanic rocks in the Turpan Basin, Sichuan Basin, Tarim Basin have exploration potentiality. (5) The technology series of oil and gas exploration in volcanic rocks have been preliminarily formed. 相似文献
972.
973.
在福建东部海域16个海湾采集了近海生物鱼、虾、贝壳、藻4大类26小类128个样品,用ICP-MS法测定15种稀土元素的含量,结果表明,轻、重稀土元素存在较大的分镏作用,明显富集轻稀土元素,即轻稀土元素的生物学效应更为明显,鱼类等近海生物稀土元素配分模式总体上与海水和世界页岩稀土元素配分模式接近。稀土元素沿福建东部海域食物链的迁移传递没有表现出明显的生物放大作用。 相似文献
974.
台湾东部海域地震频繁发生,为了改善台湾现有的预警系统,并争取地震袭击前宝贵的避难时间,台湾气象局计划建设台湾首座海底地震台站.该地震台站预计2011年建成,届时,地震预警时间将比现在提前10 S,海啸预警时间提前10 min. 相似文献
975.
文章在阐述青海东部地区主要矿山地质环境现状及问题的基础上,依据矿区废尾矿随意堆放、河道堵塞、土地资源挖损与破坏等矿山环境地质问题的特点,本着"宜林则林、宜地则地、综合治理、持续利用"的原则,针对青海东部地区人多地少、适宜农作物生长等自然环境特征,提出复坑平整、疏浚河道、回填表土、配套水利、植树绿化等综合治理措施,借以消除矿山环境地质问题,以期达到有效恢复矿山地质环境的目的。 相似文献
976.
海相碳酸盐成岩蚀变及其对海水信息保存程度的认识与评估在古海洋学和沉积地质学等学科领域研究中有着重要意义,尤其对于沉积地球化学和化学地层学等方面的研究是必不可少的基础工作。笔者通过对四川东部华蓥山仰天窝剖面三叠系海相碳酸盐岩样品的微观组构观察、阴极发光和微量元素等分析表明,大多数的样品保留了较好的原始沉积组构,具有极弱和弱的阴极发光强度、较低的Mn含量和较高的Sr含量,同时也具有较小的Mn/Sr值。只有6个样品被认为遭受了较大的成岩蚀变而对海水信息的保存程度较差,需要被剔除,而大多数的样品只遭受了较小的成岩蚀变作用,较好地保留了当时海水的信息,仍然在很大程度上代表了当时的海水。 相似文献
977.
978.
979.
Distribution of heavy metals and nutrients in rainwater in coastal regions between the southern Yellow Sea and East China Sea 总被引:2,自引:0,他引:2
Rainwater samples were collected in series in Qianliyan Island (southern Yellow Sea) and Shengsi Archipelago (East China Sea) between May 2000 and May 2002, chemical analysis for pH values,concentrations of heavy metals (Cu, Pb, Zn and Cd) and nutrients (NH4^-, NO3^-, PO43^-, SiO32^-) were performed.Results indicate that concentrations of most of the heavy metals and nutrients in rainwater show clear seasonal variation, i.e. high level in winter and low level in summer. Regionally, concentrations are higher in the southern Yellow Sea than in the East China Sea, but the annual input of heavy metals into oceans by wet deposition is similar in both stations. However, the input of nutrients by wet deposition in the East China Sea is 2-3 times higher than that in the southern Yellow Sea. In individual, Pb and PO4^3- are input to the sea mainly by dry deposition; whereas Cu, Zn, Cd and N compounds are input dominantly by wet deposition, the N/P ratios in the rainwater from two stations are much higher than those in seawater, showing a significant impact of atmospheric wet deposition on marine production and biogeochemical circulation of nutrients in these sea regions. 相似文献
980.
Distribution and Diurnal Variation of Warm-Season Short-Duration Heavy Rainfall in Relation to the MCSs in China 总被引:3,自引:0,他引:3
Short-duration heavy rainfall(SDHR) is a type of severe convective weather that often leads to substantial losses of property and life. We derive the spatiotemporal distribution and diurnal variation of SDHR over China during the warm season(April–September) from quality-controlled hourly raingauge data taken at 876 stations for 19 yr(1991–2009), in comparison with the diurnal features of the mesoscale convective systems(MCSs) derived from satellite data. The results are as follows. 1) Spatial distributions of the frequency of SDHR events with hourly rainfall greater than 10–40 mm are very similar to the distribution of heavy rainfall(daily rainfall 50 mm) over mainland China. 2) SDHR occurs most frequently in South China such as southern Yunnan, Guizhou, and Jiangxi provinces, the Sichuan basin, and the lower reaches of the Yangtze River, among others. Some SDHR events with hourly rainfall 50 mm also occur in northern China, e.g., the western Xinjiang and central-eastern Inner Mongolia. The heaviest hourly rainfall is observed over the Hainan Island with the amount reaching over 180 mm. 3) The frequency of the SDHR events is the highest in July, followed by August. Analysis of pentad variations in SDHR reveals that SDHR events are intermittent, with the fourth pentad of July the most active. The frequency of SDHR over mainland China increases slowly with the advent of the East Asian summer monsoon, but decreases rapidly with its withdrawal. 4) The diurnal peak of the SDHR activity occurs in the later afternoon(1600–1700 Beijing Time(BT)), and the secondary peak occurs after midnight(0100–0200 BT) and in the early morning(0700–0800 BT); whereas the diurnal minimum occurs around late morning till noon(1000–1300 BT). 5) The diurnal variation of SDHR exhibits generally consistent features with that of the MCSs in China, but the active periods and propagation of SDHR and MCSs difer in diferent regions. The number and duration of local maxima in the diurnal cycles of SDHR and MCSs also vary by region, with single, double, and even multiple peaks in some cases. These variations may be associated with the diferences in large-scale atmospheric circulation, surface conditions, and land-sea distribution. 相似文献