Zircon U-Pb age of the volcanic rock from the Huoshiling Formation in the Yingtai Fault Depression, Songliao Basin, China

1. Objective The Songliao Basin is a superposed basin filled with two layers. The lower layer is characterized by a fault-bounded volcanogenic succession comprising of intercalated volcanic,pyroclastic and epiclastic rocks. The upper layer is composed of normal sedimentary rocks. The Huoshiling Formation is the earliest volcanic stratum in the Songliao Basin. The report of geological age of it was rare, because of the lack of credible dating samples.

Optimization of shut-in time based on saturation rebalancing in volume-fractured tight oil reservoirs

Based on imbibition replacement of shut-in well in tight oil reservoirs, this paper expounds the principle of saturation rebalancing during the shut-in process after fracturing, establishes an optimization method for shut-in time after horizontal well volume fracturing with the goal of shortening oil breakthrough time and achieving rapid oil breakthrough, and analyzes the influences of permeability, porosity, fracture half-length and fracturing fluid volume on the shut-in time. The oil and water imbibition displacement in the matrix and fractures occurs during the shut-in process of wells after fracturing. If the shut-in time is too short, the oil-water displacement is not sufficient, and the oil breakthrough time is long after the well is put into production. If the shut-in time is too long, the oil and water displacement is sufficient, but the energy dissipation in the formation near the bottom of the well is severe, and the flowing period is short and the production is low after the well is put into production. A rational shut-in time can help shorten the oil breakthrough time, extend the flowing period and increase the production of the well. The rational shut-in time is influenced by factors such as permeability, porosity, fracture half-length and fracturing fluid volume. The shortest and longest shut-in times are negatively correlated with porosity, permeability, and fracture half-length, and positively correlated with fracturing fluid volume. The pilot test in tight oil horizontal wells in the Songliao Basin, NE China, has confirmed that the proposed optimization method can effectively improve the development effect of horizontal well volume fracturing.

Carbon emission reduction accounting method for a CCUS-EOR project

It is difficult to quantify and certify the greenhouse gas(GHG)emission reduction in the entire process of a project of carbon capture,utilization and storage(CCUS)-enhanced oil recovery(EOR).Under the methodological framework for GHG voluntary emission reduction project,the carbon emission reduction accounting method for CCUS-EOR project was established after examining the accounting boundaries in process links,the baseline emission and project emission accounting methods,and the emission and leakage quantification and prediction models,in order to provide a certification basis for the quantification of GHG emission reduction in the CCUS-EOR project.Based on the data of energy consumption,emission and leakage monitoring of the CCUS-EOR industrial demonstration project in Jilin Oilfield,the net emission reduction efficiency is determined to be about 91.1%at the current storage efficiency of 80%.The accounting and prediction of carbon emission reduction for CCUS-EOR projects with different concentrations and scales indicate that within the project accounting boundary,the certified net emission reduction efficiency of the low-concentration gas source CCUS-EOR projects represented by coal-fired power plants is about 37.1%,and the certified net emission reduction efficiency of the high-concentration gas source CCUS-EOR projects represented by natural gas hydrogen production is about 88.9%.The proposed method is applicable to the carbon emission reduction accounting for CCUS-EOR projects under multiple baseline scenarios during the certification period,which can provide decision-making basis for the planning and deployment of CCUS-EOR projects.

New Discovery of Red Paleosols with Calcite and Zeolitic Rhizoliths in the Late Cretaceous Yaojia Formation, Southern Songliao Basin,NE China

Objective Paleosols in terrestrial deposits provide important insight into paleoclimate and tectonic events(Gong Hujun et al., 2017). The Late Cretaceous continental red bed in the Songliao Basin of NE China records the paleoclimate characteristics during the Cretaceous greenhouse period. A series of data has been obtained from cores in continental scientific drilling wells(Wang, 2013). However, few investigations have reported on paleoclimatic and tectonic

Reservoir space and enrichment model of shale oil in the first member of Cretaceous Qingshankou Formation in the Changling Sag, southern Songliao Basin, NE China

The lithology, lithofacies, reservoir properties and shale oil enrichment model of the fine-grained sedimentary system in a lake basin with terrigenous clastics of large depression are studied taking the organic-rich shale in the first member of Cretaceous Qingshankou Formation(shortened as Qing 1 Member) in the Changling Sag, southern Songliao Basin as an example. A comprehensive analysis of mineralogy, thin section, test, log and drilling geologic data shows that lamellar shale with high TOC content of semi-deep lake to deep lake facies has higher hydrocarbon generation potential than the massive mudstone facies with medium TOC content, and has bedding-parallel fractures acting as effective reservoir space under over pressure. The sedimentary environments changing periodically and the undercurrent transport deposits in the outer delta front give rise to laminated shale area. The laminated shale with medium TOC content has higher hydrocarbon generation potential than the laminated shale with low TOC content, and the generated oil migrates a short distance to the sandy laminae to retain and accumulate in situ. Ultra-low permeability massive mudstone facies as the top and bottom seals, good preservation conditions, high pressure coefficient, and lamellar shale facies with high TOC are the conditions for "lamellation type" shale oil enrichment in some sequences and zones. The sequence and zone with laminated shale of medium TOC content in oil window and with micro-migration of expelled hydrocarbon are the condition for the enrichment of "lamination type" shale oil. The tight oil and "lamination type" shale oil are in contiguous distribution.

Submersible direct-drive progressing cavity pump rodless lifting technology

Submersible electrical motor direct-drive progressing cavity pump (PCP) rodless lifting was studied to solve the traditional rod-drive pump problems, such as rod-tubing wearing, low efficiency and short running time. The theoretical researches and laboratory experiments of key tools such as submersible motor and the construction technology of lifting system were introduced. The field application and economic benefit were analyzed and compared with the traditional rod pumping unit. A new low speed and large torque permanent magnet synchronous motor was developed. This motor was used to drive PCP without gear reducer, which improved the reliability and feasibility. It can run at the speed from 50 to 500 r/min with stepless speed regulation, and it can perform high efficiency and large torque. Besides, other key supporting tools, such as motor protector and flex shaft, were developed. The submersible electrical motor direct- drive PCP technology can be used in a 139.7 mm (5.5 in) casing well, with daily output ranging from 5 to 50 m3. Until now, the technology has been deployed more than 100 wells. The field application results show that it eliminates the rod-tubing wearing and saves electric energy by more than 30% compared with the traditional rod pumping unit. And it also makes the oil produced in a safe and environmental friendly way.

Lower Limits and Grading Evaluation Criteria of Source Rocks and Reservoirs of Tight Oil and Gas

1 Introduction The importance of the unconventional petroleum is increasingly prominent, with the rising demand of oil and gas in the economic and social development and the gradual consumption and depletion of conventional oil and gas resources. Compared with the shale and coal-bed gas reservoir, tight reservoir has better fracturing capability.

Authigenic silica in continental lacustrine shale and its hydrocarbon significance

Taking lake basin shales of the Triassic Yanchang Formation in the Ordos Basin,NW China and the Cretaceous Qingshankou Formation in the Songliao Basin,NE China as research objects,the characteristics and origins of different types of silica in the shales have been studied by means of core observation,thin section identification,cathodoluminescence,X-ray diffraction analysis,scanning electron microscope(SEM),electron probe and rock pyrolysis.The results shows that the origins of silica include felsic mineral dissolution,tuffite devitrification,clay mineral transformation and siliceous mineral metasomatism.The silica formed by feldspar dissolution commonly appears as spots and veins,with low degree of crystallization,and is largely aqueous opal mineral,with an average Si O2 content of 67.2%.Silica formed by devitrification of tuffite mainly occurs in two forms,amorphous silica and authigenic quartz with better crystal shape.The authigenic silica formed during the transformation of clay minerals is embedded in the clay minerals in the form of micron-scale plates and small flakes,or mixed with clay minerals in a dispersed state.The authigenic quartz formed by siliceous mineral metasomatism is in better angular crystal shape,and has an average Si O2 content of 87%.The authigenic siliceous mineral content is positively correlated with the content of terrigenous felsic minerals.The pressure solution of felsic minerals is the main source of authigenic siliceous minerals,followed by the transformation of clay minerals,and the organic matter has some boost on the formation of authigenic silica.The authigenic siliceous materials of different origins have different geological characteristics and occurrence states from terrigenous quartz,which would affect the storage performance,seepage capacity and fracturing effect of continental shale.Although the organic-rich shale has high silica content,different from terrigenous quartz,authigenic silica in this kind of shale mostly floats and disperse in clay minerals,which would have negative effect on the formation of complex fractures in fracturing,fracture support ability after fracturing,and formation of effective seepage channels.Calculating the brittleness index of shale intervals only based on the composition of brittle minerals cannot accurately characterize mechanical characteristics of continental shale oil reservoirs,and would affect comprehensive evaluation and selection of continental shale oil“sweet spots”.

A novel type curve for estimating oil recovery factor of gas flooding

A novel type curve is presented for oil recovery factor prediction suitable for gas flooding by innovatively introducing the equivalent water-gas cut to replace the water cut,comprehensively considering the impact of three-phase flow(oil,gas,water),and deriving the theoretical equations of gas flooding type curve based on Tong’s type curve.The equivalent water-gas cut is the ratio of the cumulative underground volume of gas and water production to the total underground volume of produced fluids.Field production data and the numerical simulation results are used to demonstrate the feasibility of the new type curve and verify the accuracy of the prediction results with field cases.The new type curve is suitable for oil recovery factor prediction of both water flooding and gas flooding.When a reservoir has no gas injected or produced,the gas phase can be ignored and only the oil and water phases need to be considered,in this case,this gas flooding type curve returns to the Tong’s type curve,which can evaluate the oil recovery factor of water flooding.For reservoirs with equivalent water-gas cuts of 60%-80%,the regression method of the new type curve works well in predicting the oil recovery factor.For reservoirs with equivalent water-gas cuts higher than 80%,both the regression and assignment methods of the new type curve can accurately predict the oil recovery factor of gas flooding.

Trend judgment of abandoned channels and fine architecture characterization in meandering river reservoirs: A case study of Neogene Minhuazhen Formation NmⅢ2 layer in Shijiutuo bulge, Chengning uplift, Bohai Bay Basin, East China

Based on well logging responses,sedimentary patterns and sandstone thickness,the distribution characteristics of meandering river sedimentary sand body of Neogene Minghuazhen Formation NmⅢ2 layer in the west of Shijiutuo Bulge,Chengning Uplift,Bohai Bay Basin were investigated.A new approach to calculate the occurrence of the sand-mudstone interfaces using resistivity log of horizontal well was advanced to solve the multiple solution problem of abandoned channel’s orientation.This method uses the trigonometric function relationship between radius,dip and length of the resistivity log to calculate the occurrence qualitatively-quantitatively to help determine the true direction of the abandoned channels.This method can supplement and improve the architecture dissection technique for meandering river sandbodies.This method was used to study the dip angle and scale of the lateral accretion layers in point bar quantitatively to help determine the spatial distribution of lateral accretion layers.The fine architecture model of underground meandering river reservoir in the study area has been established.Different from traditional grids,different grid densities for lateral accretion layers and bodies were used in this model by non-uniform upscaling to establish the inner architecture model of point-bars and realize industrial numerical simulation of the whole study area.The research results can help us predict the distribution of remaining oil,tap remaining oil,and optimize the waterflooding in oilfields.

Chinese-Malaysia LNG Project Launched in Shanghai

上海在 willtransmit 液化了的 2007 年 1 月发射了一个主要精力供应工程到在 25 years.Construction 上的华东经济中心的从马来西亚的天然气(LNG ) 在上海 LNG 工程的第一个阶段上开始了，它将成为 operationalin 2009。

China Top Oil Importer Status Overrated

Media reports of China surpassing the United States as the world’s biggest oil importer as shown by data from a U.S.government agency were somewhat overrated.Recently published data by the U.S.Energy Information Administration(EIA)showed that net imports of the United States and China stood at 6.24 million and 6.3million barrels per day in September of 2013,respectively.The EIA further forecast that China will start overtaking the United States by October 2013 on a monthly basis and by 2014 on an annual basis in terms of net oil imports.

China Keeps Strong Growth Momentum for Natural Gas Production

Based on the prediction made by the China Petroleum and Chemical Industry Association(CPCIA),China aims to double its annual natural gas output to 160 billion cubic meters by 2015,and produce about6billion tons of oil in the next 30 years,or 200 million tons a year.

Paleosols in an outcrop of red beds from the Upper Cretaceous Yaojia Formation,southern Songliao Basin, Jilin Province, NE China

Paleosols in an outcrop of fluvial–lacustrine red beds have been recognized in the Upper Cretaceous Yaojia Formation in southern Songliao Basin, Songyuan City, Jilin Province, NE China. They are recognized in the field by pedogenic features, including root traces and burrows, soil horizons and soil structures. Root traces are remnants of small herbaceous plants, elongating and branching downwards in the red paleosols. They are filled by calcite,analcime, and clay minerals in spaces created by the decay of the plant roots. Burrows are found near the root traces with backfilled cells made by soil-dwelling insects. Soil horizons include calcic horizons(Bk horizon) with continuous calcareous layers, argillic horizons(Bt horizon) with clay films and dark brown to black iron-manganese cutans, vertic horizons(Bw horizon) with slickensided claystone, and deformed soil structure and gleyed horizons(Bg horizon) with mottles and reticulate mottles. Soil structures of the paleosols include pseudo-anticlinal structures,subangular blocky structures, and angular blocky structures. The micro-pedogenesis characteristics are also observed, including micrite pedogenic minerals and clay skins. Based on the pedogenic features above, paleosols types including Aridisol, Alfisol, and Vertisol are interpreted in the red beds of the Yaojia Formation. Forming in the Late Cretaceous, the paleosols can provide more details about the seasonal climate conditions and terrestrial sedimentary system in lacustrine basin.

Formation mechanism of high-quality reservoirs of Lower Cretaceous volcaniclastic sedimentary rocks in Songliao Basin

High abundance gas reservoirs were discovered in the volcaniclastic sedimentary rocks of Wangfu faulted depression in Songliao Basin,but the distribution pattern and formation mechanism of this type of high-quality reservoirs were not clear.In the Shahezi Formation of Well Block CS6 in Wangfu faulted depression,the void space type,reservoir property,pore throat and pore diameters were studied by means of the casting thin section,helium intrusion porosimetry,mercury intrusion porosimetry(MIP)and nuclear magnetic resonance(NMR)methods,moreover,formation mechanism and main controlling factors of the high-quality reservoirs were discussed.Results showed that lithology of high-quality reservoirs consisted of the volcaniclastic sedimentary agglomerate and the volcaniclastic sedimentary breccia,and exhibited the coarsening-upward characteristics.Furthermore,three types(seven subtypes)of void spaces were identified,among which the intragranular vesicles with primary abundant pores were uniquely developed in the high-quality reservoirs of volcaniclastic sedimentary rocks,indicating this high-quality reservoir belonged to the large-pore and small-throat reservoir;porosity and permeability of volcaniclastic sedimentary agglomerate were slightly higher than those of volcaniclastic sedimentary breccia,and both were significantly higher than those of sedimentary rock in the Shahezi Formation,the porosity was closely related with the burial depth.Formation mechanisms of reservoirs in the volcaniclastic sedimentary rocks were release of volatile matters in parent rocks,grain support,dissolution and tectonic modification,among which the former two were the main controlling factors.The high-quality reservoirs over the study area were mainly distributed in the central part of the fan of volcaniclastic sedimentary rocks,among which the grain-supported,coarse-grained volcaniclastic sedimentary rocks with high content of intragranular vesicular detritus and burial depth less than 3000 m were the most favorable area for development of the high-quality reservoirs.

Why Can China Realize the Continental“Shale Oil Revolution”?

0 INTRODUCTION Continental shale oil is a strategic alternative resource to ensure the safety of national oil supply and improve the level of industrial innovation.China is a large country of continental oil resources,accounting for 90%of the total onshore oil resources;and China is also a major producer of continental oil,accounting for about 93%of the total oil production(Yang et al.,2019;Jia et al.,2018).