Yang F.,Key Laboratory of Exploration Technologies for Oil and Gas Resources |
Yang F.,China National Petroleum Corporation |
Zhao Z.-Q.,China National Petroleum Corporation
Wutan Huatan Jisuan Jishu | Year: 2012
The seismic attribute analysis technology is always main research content of seismic special processing and the interpretation. Along with correlation theory development, The seismic attribute analysis technology already be applied each period. S basin can be described by stronger heterogeneity, small number of wells, larger spaces 2D seismic lines and more difficult reservoir prediction during earlier stage exploring. The seismic wave can change with sediment stratum variety, so application of seismic attributes analysis can predict the advantage reservoir with no u-sing well constrained, that is, applying seismic attributes to sandstone reservoir lateral prediction. By using of geologic statistics method, three seismic attributes are chosen, they are average absolute amplitude, average instantaneous frequency and effective bandwidth. Absolute amplitude is used to search rich sandstone area. The broad effective bandwidth indicates non-uniform reflectivity suggesting complicated bedding; narrow bandwidth indicates simpler and smoother reflection character suggesting uniform bedding patterns. In some situations, gas-saturated sands attenuate higher seismic frequencies, causing anomalously low average instantaneous frequencies coincident with RMS amplitude anomalies (bright spots or dim spots). The application of seismic attributes analysis provided an important proof in exploration and making plan.
Zheng S.,Key Laboratory of Exploration Technologies for Oil and Gas Resources |
Zheng S.,Yangtze University |
Wang C.,China University of Petroleum - Beijing |
Kong X.,Yangtze University
International Journal of Earth Sciences and Engineering | Year: 2015
With the increasing scale of cementing operation, the geological conditions are more and more complicated. The practice of cementing shows that the surge pressure caused by instantaneous driving pump can lead to the underground leakage easily, this paper considering the characteristics of fluid and casing, establishes the calculation model for calculating surge pressure, and introduces the numerical solution method. With the programming calculation using the actual data of a well, the results show that the effect of surge pressure cannot be ignored. When the time for driving pump is shorter, the surge pressure is larger, the conclusion is important to optimizing the pump operation. © 2015 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.
Liu S.Y.,Yangtze University |
Hu M.Y.,Yangtze University |
Dai W.Y.,Key Laboratory of Exploration Technologies for Oil and Gas Resources
Advances in Energy Science and Equipment Engineering - Proceedings of International Conference on Energy Equipment Science and Engineering, ICEESE 2015 | Year: 2015
Based on core observation and description, combined with various sedimentary lithologic marks, such as rock types, sedimentary structure, and characteristics of logging curve response, this paper analyzed the depositional facies and its characteristics of Fuyu reservoir (Kf) 4th member of Quantou Formation in southern Zhaoyuan area. The results show that the two types of facies, shallowwater delta sedimentary facies and meandering river, are developed in the area. They are further divided into five kinds of subfacies and ten kinds of microfacies. The types of sand bodies mainly include bed-side beach deposition, delta plain distributary channel sand body as well as delta front underwater distributary channel sand body. Based on previous studies, combined with high-resolution sequence stratigraphic division, Fuyu reservoir 4th member of Quantou Formation can be divided into a long-term cyclic sequence (LSC1), three middle-term cyclic sequence (MSC1 to MSC3, from bottom to top) and seven short-term cyclic sequence (SSC1 to SSC7, from bottom to top). The sedimentary microfacies plane distribution maps in the studied area are established according to the analysis results and then the paper analysed the plane distribution and vertical evolution of it. Vertically, the changes in the dephts of the water vary from shallow to deep. During the period of Q4-SSC7, the water depth arrived at a maximum value. The results show that the shallow water delta deposits are developed in the area, and the types of sand bodies are mainly composed of delta plain deposits. During the period of Q4-SSC1, meandering stream and shallow water deltic plain are developed in the whole area, the channel sand body is in its maximum thickness, and it is the best time for the development of sand body as reservoir. © 2015 Taylor & Francis Group, London.
Qiu X.-S.,Key Laboratory of Exploration Technologies for Oil and Gas Resources |
Yang B.,Yangtze University |
Hu M.-Y.,Key Laboratory of Exploration Technologies for Oil and Gas Resources
Natural Gas Geoscience | Year: 2013
The middle Yangtze region is one of the most important petroleum provinces, in which the shale of Wufeng-Longmaxi Formation is widely distributed and the exploratory well in Western Hubei and Hunan provinces has good gas show. At present, research of shale gas in China is hot, while the production of shale gas in North America has achieved success. Therefore, in our country, strengthening the study of characteristics of shale reservoirs and gas content has great significance for shale gas exploration and production. In this paper, based on the observation of field outcrops and cores, integrating with analysis of rock slice, mineral content, physical properties, organic geochemistry and other methods, the features of lithofacies, mineral, reservoir space and gas content of shale in Wufeng-Longmaxi Formation are studied in detail. The results show that shale of Wufeng-Longmaxi Formation in the study area is mainly composed of mud shale, siliceous shale, graptolite shale, carbonaceous shale and silt shale, quartz and clay consisting of essential minerals. The main reservoir space types are matrix pore, organic pore, dissolved pore, microfracture. Moreover, the content of free gas and adsorbed gas, which is mainly controlled by total porosity and organic carbon content, ranges from 0.09-0.17m3/t and 0.20-0.84m3/t respectively. The total gas content is between 0.29m3/t and 1.01m3/t. According to the definition standard of shale gas, the favorable region is located at Enshi-Pengshui area, and the estimated resources range from 0.23×1012m3 to 0.81×1012m3. These features indicate that the shale of Wufeng-Longmaxi Formation in the middle Yangtze region has good shale gas exploration prospect.
Huang G.H.,Yangtze University |
Huang G.H.,Key Laboratory of Exploration Technologies for Oil and Gas Resources |
Zhang M.,Yangtze University |
Zhang M.,Key Laboratory of Exploration Technologies for Oil and Gas Resources |
And 2 more authors.
Science in China, Series D: Earth Sciences | Year: 2010
In the processes of discrimination between oil-cracked gases and kerogen-cracked gases, Behar and Pinzgofer et al.'s results were adopted in the former researches, in which the ratio of C2/C3 is basically a constant while the ratio of C1/C2 gradually increases in the course of primary cracking of kerogen. Otherwise in the course of secondary cracking of oil, the ratio of C2/C3 by cracking, the ratios of C2/C3, C1/C2 or C1/C3 will all be increased with the growth of thermal conditions. In comparison, the ratio of C2/C3, which is affected by genetic type to some comparatively less extent, mainly responds to the maturity of gases, while the value of C2/C3 is about 2, and that of C2/iC4 is about 10, and the corresponding value of Ro is about 1. 5%-1. 6%. The influence of gas source on C2/C3 is less than that of gas maturity, otherwise C1/C2 (or C1/C3) is obviously affected by cracking matrices. The ratios of C1/C2, C1/C3 of oil-cracked gases are less than that of kerogen-cracked gases, under the condition that the ratios of C2/C3 are similar in value, so are the value of dryness indexes. There exists wide diffidence between this view and the former discrimination method in theory. The analysis of the spot sample indicates that we can apply the above basic view to dealing efficiently with the problem of the discrimination between oil-cracked gas and kerogen-cracked gas. © 2009 Science in China Press and Springer Berlin Heidelberg.