The Research For Qinjiatun Oil Field Deposit Geology And Exploitation

Qiniiatun oil field met oil layer in k1q when drilled SN77 well in 1998.This field began the production in 1999. The accumulative reserves of the oil was 10090kT.The area of the oil was 9.5km2. At present, the develops situation is: On the one hand, we have a certain understanding to the oil field, but many difficult problems has not been solved. So many difficult problems is hindering the oil field smooth development; On the other hand, we already have many materials: we have log material, tests oil materiaU extractive oil material along with the number of well drilling growth except earthquake two-dimensionaU earthquake three-dimensional. Therefore we has pointed conducts the research to this area utilizing geology information, earthquake information, log information, tests oil information, extractive oil information. It appears very important to obtains the oil deposit characteristic further understanding, adjust the extractive relations of poured water area and research a feasible poured water to has not been poured water .So we develop research work for this project. In stratigraphic correlation process, We take the sedimentology, the petroleum geology theory as the instruction, carries on the stratigraphic correlation and divides comprehensive using drill well materiaU log materiaU earthquake three-dimensional materiaU tests oil material and extractive oil material.,In order to guarantee contrast accuracy and reliability we use the cycle correlation method and the step control correlation method to effectively control sandstone group especially control subzone sandstone group. NongXI was divided into 2 sandstone groups and 9 subzones (on sandstone group 3, under sandstone group 6),resting on three clear contrasts symbols.Small I section was divided into 3 sandstone groups and 11 subzones resting on the region not entire kneads doughs thin neck mudstone section on the bottom of NongXI section, funnel mudstone section on the bottom of Small I as well as auxiliary indicated layers. On the aspect of further knows in the structure characteristic, we fully unifies the well drilling material, the logging materiak the exploitation dynamic materiak the three dimensional seismic interpretation, has carried on the structure understanding. Said to the NongXI section that the overall shape performance for the major axis anticline which axial north east approaches, the length and breadth compares is approximately 4: 1, trap area is 6Km2, structure scope 60m, the structure high spot is located SN77 and QK5-9, in QK3-11, QK5-11 place is the saddle. Said to the Small I section that the structure overall shape has not too big changes contrast with the NongXI section. The conformation has slightly partially change only because the structure high spot has slightly change.Generally speaking, the conformation compound well. In the work area, the fault altogether has 12, increases 4 faults. On the aspect of researching deposition characteristic, we carefully analyzed the sedimentary environment, the sedimentary fades in the NongXI section and the Small I section. we studied the different micro deposition characteristic taking the monolayer as the unit, Carefully elaborated the different micro characteristic and the granulated substance body distributed characteristic , established the sedimentary facies pattern , laborated environment of deposition, deposits the micro spatial distribution as well as the deposition evolution history in this area. we judged the thing source direction is northeast from the extending direction of the sandstone and the ancient landform characteristic. The Small I and NongXI section of depositions characteristic research indicated: the work area belongs to the delta front Subfacies deposition, mainly includes the submarine distributary channel, the divergence the bay thin layer granulated substance micro, the divergence bay putty micro 3 micro, has experienced the weak -strong -weak -strong successional variation process. This period has included secondary entering water, withdrawing water as well as the river course change vicissitude many times. The submarine distributary channel back and forth swings, changes course frequently, occurs laterally migrates many times. From deposits the micro distribution as well as the evolved situation, the NongXI section of depositions characteristics and the Small I section have certainly similar, even has certainly inherits the nature. On the aspect of researching reservoir characteristic, We study the lithological characteristic and the natural characteristic of reservoir mainly rest on the drill well materiak logging material. We described the reservoir plane and longitudinal extension and the reservoir connection.The NongXI section of reservoirs lithological character mainly is the novaculite, next as the siltstone and center the sandstone and very few grits in addition; The reservoir rock type take the arkosic sandstone primarily, next as the rock debris arkosic sandstone. The reservoir nature has the following characteristic: The porosity and the penetration coefficient change the lifference along with the depth increase, the reservoir belongs to the the middling hole, middling -high seepage characteristic. The Small I section of reservoirs lithological character mainly is the arrkosic sandstone, by the hovaculite primarily, the few siltstone. The reservoir has the middling hole, middling -high seepage characteristic. Controlled by The sedimentary environment. The reservoir granulated substance body listributed characteristic is: the river course granulated substance body hssumes the strip belt-shaped distribution, the divergence the thin layer aranulated substance assumes the mat shape distribution; On longitudinal, the granulated substance body long-term growth, superimposes repeatedly assumes layered distributes mutually. On the aspect of researching oil and water distributed characteristic, We carried on the massive logging material to analysis the oil and water extension characteristic and the oil deposit characteristic. Ascertained the type of oil deposit. The NongXI oil layer: on longitudinal, the oil layer main centralism distributes in the 4 main forces level which is upside 3, underside 1, underside 2,underside 3. This area containing oil is wide. In the plane, the oil layer mainly assumes the strip belt-shaped, the small laminated distribution, always contains oil the area is 1.05 km2, oil layer thickest 17m, thinnest 4.1m, average core interval 9.1m, the oil layer well drills meeting rate is 72%. The oil layer plane distribution was mainly controlled by deposits micrcK the lithological character, the structure position and the fault. The oil deposit type belongs to the structure lithologic deposit. The Small I oil layer: on longitudinal, the oil layer main centralism was divided into 4 main forces level which is Small I-11, Small I12, Small I31, and Small I 32. In the plane, the oil layer mainly assumes reveals small laminated, the lens shape distribution, always contains oil the area is 0.91 km2, oil layer thickest 32.4m, thinnest 9.8m, average core interval 15.6m, the oil layer well drills meeting rate is 76.9%. The oil layer plane distribution was mainly controlled by the structure position, deposits micro and the fault. The oil deposit type belongs to the water stratified deposit. Aiming at the main exploitive question at present, we synthetic studied theSN106 sub-area oil deposit formation, the well pattern, the well spacing, pours water way, Had determined the formation, the pattern well spacing, the water-injection exploitation way and the reasonable perquisite number of wells ratio. Carried on the overall system adjustment work to the oil deposit. Deployed 3 wells for consummate the registration well pattern. Picks the well to the oil deposit note to carry on the comprehensive optimization for the improvement water-injection exploitation effect. Definited oil water well 15, oil well 7, water well 8, after the adjustment the oil field water drive control degree reaches 96.9%, the oil field water drive recovery ratio is 28.9%. Pours water the feasibility study result to the SN77-SN78 sub-area to indicate that, the reservoir can satisfiedly pour water the request, the implementation water-injection exploitation may make this final recovery ratio to enhance about 10%. In the entire research process, we always take the first material as the foundation. We synthesis applied the well logging interpretation achievement, tests oil material, extractive oil material and fully has digested the predecessor each kind of research results. We carried on the careful research work from the geology and exploitation aspects. We have completed in the entire region comprehensive oil deposit geology research work. It will provide the science basis for reasonably exploit, the oil layer transformation, enhances the recovery ratio, the maintenance oil field stable production from now on.