Well Su 75-70-6H is the largest open hole horizontal well fracturing built by domestic technologies. Orientation of horizontal section is north-south. Microseismic monitoring shows whether fractures are generated, locations and patterns of fractures, and further provides a guide for fracturing operations; monitoring can also identify location of possible fracturing fluid leakage, provide early warning of sand blocking and help evaluate the effectiveness of stimulation. It proves that domestic manufactured fracturing downhole tools can be used.The result of microseismic monitoring accuratly reflect the operation process, as well as guide it.
This paper discusses the long 6 extend oilfield injection wells because the transfer group and the leading edge of microseismic monitoring of water. Yanchang Oil Field Oil Production Plant 4237 Zichang water injection wells set the direction of NEE to the front edge by the impact of in situ stress field in the direction of the strong. That injector network layout should also refer to the in-situ stress field direction and the original crack direction.
Well J-253 is located in the J-11 fault block of North China oil field. The direction and geometry size of hydraulic fracture are affected by the stress, geological structure and faults, as well as hydraulic sand blasting. The direction of the initial artifical fracture is at NNE, deviating from the direction of the maximum herizontal principal stress. Then it turns to the direction of the maximum horizontal principal stress and normal direction of contour. Moreover, there are significant fissures lined around the well. It has typical significance to study the artifical fracture direction and geometry of Well J-253.
This paper describes horizontal effects of CBM (coal bed methane)fracturing, obtained from microseismic monitoring in Qinshui Basin. It indicates that adjacent wells perpendicular to man-made fractures have adverse effects, including reduced production flow rate, depletion, and watering during fracturing operation simultaneously, while wells along manmade fractures response lag. This discovery shows that the horizontal compression of fracturing could have adverse impact on production of adjacent wells, and fracturing designer should be aware of it.
After a period of time of production, in some wells, the crude oil at the old crack has basically been taken out, but there's certain amount of recoverable reserves. In order to improve the efficiency of these wells, refracturing is required. Temporary plugging agent in refracturing plays a very important role; it is the key to the success of refracturing. In this article, a new kind of temporary plugging agent has been developed, we have done lots of laboratory testing researches about its performance and temporary plugging effect. And, nonlinear finite element numerical simulation analysis has been adopted for temporarily blocking crack and the impact of the wells. It is can be seen from the experiment and finite element analysis that the new temporary plugging agent has a good effect; it has no secondary pollution of wells. Temporary plugging agent can provide protection for wells, and it has a good prospect.
This paper introduces a new type of perforating completion technology modularization wire line perforating technology．It uses monocable to run the hanging device of the perforator to the desired depth；then the full modular perforating guns required by the perforating operations are run to the well one after another；at last，the perforating charges are detonated．With the technology，the aim of running multiple guns individually and detonating at one time is realized．Based on this technology，with a special guiding design，the wire line oriented perforating is completed．The technology is making full use of the special features of the wire line conveyed method，including less equipment，easy operation，and short job time，etc., also fulfills some functions of tubing conveyed perforating，such as underbalanced perforating in the whole well，preventing blow out，etc．In addition，in the perforation in high pressure oil and gas wells，the modular perforators can be dropped to well bottom．Thus the wells can produce directly without restriction to the high pressure oil and gas．If the down hole tools need to be pulled out，the operation can be completed with the wellhead lubricator for the tool in the well is not long．
This study demonstrates results of waterflood front mapping and microseismic monitoring of Red-032 well zone. Microseismic monitoring results are in consistent with those of geological simulations and seismic amplitude distributions. It concludes that microseismic monitoring is capable of detecting locations of water flow drive, which provides evidence to optimize waterflood plan, improve injection/production methods, and increase waterflood efficiency.
Microseismic monitoring is capable of determining locations of waterflood front drive, optimal waterflood direction, waterflood wave, water spread area and etc., and then interpolates fracture patterns, based on microseismic wave occurred from waterflooding. After brief description of principles of passive microseismic monitoring, this paper analyzes results of application of microseismic monitoring on waterflood front at Daqing Oilfield western periphery, in combination of dynamic and static geological information. Field application asserts that microseismic monitoring has good prospects in fracturing studies of low permeable oilfield, and is great importance to improve recovery of low permeable oilfield.
This paper describes arrival time of microseismic signals, which were obtained from monitoring fracturing and waterfloodand were used to interpolate mechanisms of micro-earthquake and verify reliability of fracturing and waterflood monitoring. It shows that fracture orientation, waterflood front geometry, and microseismic mechanism nodal plane are consistent, and monitoring results are reliable. This study depicts a selfcheck approach to verify dependability of microseismic mapping itself, and it is an important measurement method for fracturing and waterflood projects of deep formations when no alternative verifications are viable.
This paper discusses the use of microseismic monitoring for water reservoir and mines in hazardous earthquake forecasting. Author deems that monitoring expanded to microseismic level can enlarge database and improve credibility of prediction. Actual results of microseismic monitoring underlies such expansion. With advancement of technology and earthquake forecasting principles, microseismic monitoring can achieve breakthrough in hazardous quake forecasting of water reservoirs and mines.
To meet requirements of rapid exploration and development in Hailar Basin, effectively solve technical challenges of dependability of drilling formation sample such as formation debris logging, geochemical logging to identify oil and gas, and evaluate reservoir, light hydrocarbon analysis logging was applied in Hailar Basin, in the light of optimizing suitable advanced logging technologies. This paper entails the principles and features of light hydrocarbon logging, and analyzes the results of practical applications of this technology, which lays a solid foundation for promoting this technology.
Modularization wire line perforating technology uses monocable to implement the perforator transmitted through oil well. Its design idea is different from the general perforator technology. Perforating gun system adopts the modular design to implement oriented perforation by a special technology. The technology uses the advantage of monocable and oil well to solve the problem in the transmission. The paper focuses on the introduction of the system structure and technological principle of the modularization perforating technology and the application effect of oriented perforation for deviated well .
Ultra low permeability formations in outer area of Daqing western is characterized by deeply buried, thin, and sand scattered. Note that first waterflood in such formation where water contained capability is poor and it's difficult to recovery oil efficiently, this paper describes pilot studies of pressurized water injection on single well to ensure effective waterflood drive and achieve goal of “sufficient water injected and implementation well” on the basis of thorough theoretical study and many demonstration. After injection completion, effective waterflood drive and significant production improvement was achieved.Use of passive seismic monitoring and isotope logging has increased water contained capabilities, eased the complexity contradiction between layers, and improved reservoir effectiveness. Water injection front drive and spread area increases or decreases, following changes of pressure of water injection. Pressurized water injection can increase coefficient of water injection front drive and enhance oil recovery, improve development efficiency of ultra low permeability reservoir,it provides a reference for development of ultra low permeability oilfield.
Aiming at the characteristics of low permeability and small porosity of high pressure low permeable reservoir, fracturing mapping was employed during transformation. Information of fracture azimuths (direction), length, height (range), occurrence and directions of underground principle stress provides basis for oncoming well placement and well network optimization. Since 2008, 79 fracturing mapping have been performed successfully in Xianhe region, which offers great support for the increasing development of low permeable reservoir.
The non-producing reserves in Chaoyanggou and Changchunling blocks in outlying of Daqing Oilfield belong to low permeability Fuyu reservoir, and when apply the conventional vertical wells development technology in these areas, we get low single well productivity and poor development benefit. To further improve its development effect and explore economic exploitation methods in low permeability reservoirs, the horizontal near-balance drilling and open hole completion techniques are adopted to reduce the reservoir pollutions caused by drilling and well cementing. What's more, we also combine drilling tures with the oil expansion packer process to carry out fracturing transform. The results of oil production test and commissioning show that near-balance drilling and open hole completion technology can protect reservoirs effectively in low permeability reservoirs. Besides, using open-hole horizontal reservoir fracturing improvement can increase daily oil production of single well, which has important significance to further improve development effect of low permeability reservoirs.
The artificial fracture position and the well row direction influence the exploitation effect of low permeability reservoir. In the process of creating artificial fractures, we apply microseismic to monitor their direction, location, orientation, length and height, and determine the well alignment direction combined with the stress orientation, all of which establish well foundation for improving the development effect of A block.
Aiming at the remaining oil distribution feature in ultrahigh water cut stage and oil layers depositional features in the north of Saertu Oilfield, guided by the hydrodynamic principle, based on the practical experience and analysis of cyclic water flooding in combination with numerical simulation, cyclic water flooding and various parameters are optimized, and layered cross injection with changing fluid direction is adopted so as to improve the development effect which has acquired favorable result in practice.
By using testing, coring and logging data of part exploratory well, evaluation well and development well in A block, we analyzed and counted the relation of “four characters ”, that is lithology, physical character, oil-bearing and resistivity , and established the explanation standard of oil, gas and water layers. Mainly using data of rotatory sidewall coring and drilling well coring, we analyzed and counted reservoir lithology characters and physical properties; by using coring wells and testing oil wells, we analyzed and counted the growth condition of oil and water layers. By using data of charts method, we got the correlation of lithology, physical character and oil-bearing. Oil, gas and water layers were corresponding to different logging curve values and the curve with the highest coincidence rate was chosen as final explanation standard to direct the block perforation program.
To develop new technology and advanced approaches to reduce viscosity of crude oil reservoirs, increase permeability and improve flow rate of high viscous light oil reservoir, and then further improve recovery of block with more intensive well network, steam-flooding pilot studies were implemented from 2006 to 2008. Based on the formation nature characterized of high viscosity, low permeability, high clay content, and thin effective thickness, in-house physical modeling was undertaken in feasibility study; steam injection parameters and injection methods were optimized with numerical simulation; ground anti-swelling and wellbore heat insulation technologies were carried out; field tests included 3 wells, and cumulative increase of recovery was 1.81×104 t. The studies indicated suitable reservoir geological conditions for steam-flooding extraction of low permeable high viscous light oil reservoir.
Microseismic (MS) monitoring is a hot topic in the applied geophysics recently. The MS mechanism and histories are introduced firstly in this article, and then the instruction of the MS equipment such as acquisition strategies, optimal sensors, array design, digital-signal processing, event location, velocity calibration, and monitoring deployment, is discussed. MS is a great technology with a long future, and we need to foster the understanding and acceptance of this technology.
Stress orientations of regional stress field is the main influencing factors for the hydraulic fracture. Most of the hydraulic fracture extend along the greatest principal stress direction, which also affected by geological structure, original faults and faulting plane. Lots of hydraulic fracturing have been monitored in the Tamtsag Basin of Mongolia and Hailaer Basin in the Heilongjiang province of China, which provided information for the will distribution. It is proved that the rule of the greatest principal stress direction except some anomaly directions. It will be great helpful for us to study these anomaly cases. The following of this article will analysis the mechanism of the anomaly directions and reasons for high production.
It has been proved by successful experimental study and application of the new fracturing technology, which create two fracture, significantly improving contact area between fracture and low permeability reservoir, and increasing productivity as well. Normally the permeability of the low permeability block in the Changqing oil field is below 0.5 mD by low-permeable cores analysis. It is a tough task to development the oil through the general methods due to geological condition, watering well distribution and fracturing technology. Volume fracturing is proposed to increase the productivity by multiple crack fracturing since 2006 in Changqing oil field. The fracture initiated from the hole by the perforating shot, then turn the direction of the maximum level principal stress in the physical model research. Two lines of perforating shot are fired in the different depth of the oil reservoir, with an angular between the shots and the maximum level principal stress, liking letter “X”, paralleling in the distance. The oriented perforating technology for the multiple crack fracturing is presented and applied in the Changqing oil field. It is proved that multiple crack created by the downhole microseismic monitoring, productivity also increased 38.1 % compared to the adjacent by oriented perforating and multiple crack fracturing, the characteristics of the reservoir has been analyzed.