To study the influence of changes in the coal seam mechanical characteristics at depth on the stress relief effect of a borehole, this paper established the relationships between the borehole spacing, elastic modulus, and Poisson’s ratio of the coal seam. It then analyzed the stress relief effect of different borehole spacings in different coal qualities in a deep coal seam, using the FLAC3D numerical simulation software. The results indicated that after boreholes with different spacings were drilled in the deep coal seam, the peak stress value of the roadway-surrounding rock was transferred to the deep coal body, and the original peak stress position was reduced to varying degrees. Under the premise of ensuring the stress relief effect and improving stress relief efficiency, the relationship between borehole spacing and the elastic modulus of the coal seam was a negative exponential function, whereas the spacing of boreholes and Poisson’s ratio of the coal seam had a logarithmic function relationship. The research conclusions were applied to the − 1000 West No. 1 mining area in the Tangkou coal mine, which achieved good stress relief results.

Rock burst caused by mining-induced tremors is a dynamic disaster in mines that can cause great damage. Based on the mining-induced tremor that occurred at the MKQ Coal Mine, Inner Mongolia Autonomous Region, China, on March 3, 2018, the present paper studies the mechanism of mining-induced tremor occurrence using theoretical analysis, numerical simulation, and focal mechanism. The study found four inferior strata and a primary key stratum in the overlying strata on LW3102, and discovered that upon breaking the key stratum movement releases a large amount of energy thereby causing the mining-induced tremor. When the internal stress of the coal pillar in the air-return way of LW3102 reaches 72.77 MPa, the static load stress concentration appears in the coal body near the air-return way, thereby facilitating easy coal body instability due to the overlay of the dynamic load, which in turn produces the rock burst. Based on the analysis of the moment tensor theory, this study finds the ratio of the moment tensor double couple part (MDC) of the strong mining-induced tremor focal to be 8.91%, indicating that the tensile fracture appears in overlying strata on LW3102, and a large amount of energy is released, thereby inducing the mining-induced tremor. The rock burst of the working face is controlled by applying control measures.

The aim of this study is to resolve the present control problems and the corresponding high-strength anchor cable control technology in deep large section roadways. This study was based on the Hoek-Brown criterion and the upper bound theorem of the limit analysis and also considered the stress of surrounding rock in the roof and the effect of supporting the load. On the above basis, the roof caving mechanism of large-section roadways was acquired. Furthermore, a design method for roofs was put forward for the minimum length and the pre-tightening force of an anchor cable. Since the design parameters of anchor cables was affected by established sensitivity indexes, it is important to investigate the effects of established sensitivity indexes on factors, such as the roadway's width, the specific weight of the rock mass, the stress in the surrounding rock, the compressive strength and the tensile strength of the rock mass, anchor cable layout spacing and vertex anchor cable laying angle. According to the actual field conditions,engineering suggestions are proposed for controlling surrounding rocks in the deep large-section roadway. Finally, this design method was applied to determine the roof anchor parameters of transport gateway of 1305 Island Coal Face in the Kilometer Deep Well Zhaolou coal mine, which effectively controlled the deformation of surrounding rock. From research results, only when the roof anchor cable was anchored in stable rock and enough pre-tightening force was exerted, the roof rock caving and damage can be effectively controlled in high-stress large-section mining roadways. It is found that roof pre-tightening force for anchor cable decreased with the increase of tensile strength, compressive strength and empirical parameter A of rock mass. Besides, this roof pre-tightening force increased with increasing the width of the roadway, the specific weight of rock mass, the stress in the surrounding rock, the compressive strength and the tensile strength of rock mass, anchor cable layout spacing, vertex anchor cable laying angle and empirical parameter B of rock mass. Moreover, the highest sensitivity of all the influencing factors turned out to be the surrounding rock stress. This indicates that special attention should be paid to the influence of in-situ stress of the surrounding rock when designing the deep high-stress roadways. Therefore, the effective release of the surrounding rock stress can be achieved by using the high strength, high elongation anchor cable and adding the yieldable device. Meanwhile, the integrity of the surrounding rock can be improved by applying high pre-tightening force and grouting reinforcement, resulting in better control performance of surrounding rock.

The invention discloses a mining influence tunnel dynamic monitoring and stability evaluation method which comprises the following steps: step 1, arranging a high-precision micro-seismic monitoring system and an introscope; step 2, collecting data before mining influence; step 3, collecting data after mining influence, wherein the specific implementation steps of the step 3 are the same as those of step 2; step 4, analyzing the stability of surrounding rock, namely respectively calculating to obtain a surrounding rock rupture range increase rate, a surrounding rock rupture energy increase rate, a surrounding rock rupture event unit volume density increase rate and a surrounding rock rupture degree increase rate based on a surrounding rupture position, surrounding rack rupture energy, surrounding rock rupture times and surrounding rock rupture degree before and after mining influence; step 5, quantitatively evaluating the tunneled tunnel stability below a coal pillar of mining influence, namely, based on surrounding rock evaluation values obtained in the step 4, establishing quantitative evaluation indexes of tunnel tunneling stability under mining influence by use of a weight analysis method, and performing quantitative evaluation on the tunneled tunnel under mining influence.

为推动企业改革发展、转型升级,山东能源新矿集团坚持以辩证、系统、精准、法治和战略思维审视现实、谋划未来,实施导向驱动管理,调动了集团上下干事创业的积极性,各项工作取得突破性成果.今年二季度以来,在产量同比减少、煤价同比降低,并消化一季度亏损的情况下,企业实现整体扭亏为盈.

针对龙口矿区梁家煤矿典型软岩巷道-4606改造开切眼巷道围岩控制难题,通过现场监测和试验,分析原支护方案下围岩变形破坏机制.煤层结构复杂,围岩易膨胀、软化,围岩破坏范围大,拱架变形破坏严重,锚杆支护潜力无法有效发挥是巷道变形破坏的主要原因.支护构件锚固性能试验表明,与注浆前相比,注浆10 d后注浆锚杆拉拔力提高214％,高强锚索提高89％.在此基础上,以锚注支护为核心,实施了U型棚+注浆锚杆,注浆锚杆+高强锚索两种联合支护对比试验方案.结果表明:方案实施后,巷道围岩变形量小于原支护方案59％以上,锚注支护可有效控制该类条件下巷道围岩变形;两种试验方案的围岩整体平均变形量相差6.6％,采用注浆锚杆+高强锚索联合支护方案可替代传统的U型棚支护.

For the geological conditions of two soft coal seams, mechanical models for rockburst occurring in two soft coal seams. Mechanical analysis and field practice of these models show that the main causes for rockburst in deep two soft coal seams are the stress concentration and energy accumulation in the soft alluvium that is clamped in the upper force source layer and the lower stable layer, and the energy accumulated from mining activities which releases to crushing mitigation areas, causing instantaneous ejection of coal and rock blocks and forming the rock burst. Through the researches on stress, energy, material conditions and inducing factors for burst of deep two soft coal seams, the prevention measures for rockburst of block structure of the roof support structure such as transferring stress, maintaining the stability of chain pillars, strengthening coal side, and loosening working slope are formulated. Field practice is made so as to realize the safe and high-efficiency non-impact mining at working faces.

Based on the study of litho-, bio- and seismic stratigraphy, this paper describes how to use drill cores, well logs, seismic data, paleontological data, and lithostratigraphic data to correlate the Dongying Formation in the Liaodong Bay. The paper also discusses the implications of the stratigraphic correlation scheme for hydrocarbon exploration in the Liaodong Bay.

The 36-A Oil Field in Suizhong,Liaoning is a hundred million ton-sized oil-gas field in the Bohai offshore field. The Palaeogene oil reservoirs are mainly concentrated in the second member of the Dongying Formation. The present paper deals in detail with the microscopic features and controls of the hydrocarbon reservoirs in the study area. The favourable reservoirs are mainly organized in the lacustrine delta front subfacies in the second member of the Dongying Formation. The diagenesis,clay mineral content,temperature-pressure field and fluid filling as main controlling factors of the physical properties of the oil reservoirs are believed to be responsible for the devolopment of vast extensive distribution,tremendous vertical thickness,high porosity and high permeability favourable reservoirs.

According to the problems of the mine pressure bumping accident frequently occurred in coal mining face in the seam island,the defect method was applied to prevent and control the mine pressure bumping in the high stress region of the coal mining face in the seam island,the artificial defect mass was applied to migrate the stress field of the coal mining face in the seam island,the energy continuously and slowly releasing could form a pressure releasing and protection zone during the stress filed migration process and thus the danger of the mine pressure bumping could be reduced.The pressure released gateway,blasting boreholes,large diameter boreholes and other artificial defect technical method applied could effectively make the stress migration forward to the deep of the coal mining face and could have an energy released effect.An active stress monitoring and measuring technology was applied to the effect inspection.The observation results showed that based on the artificial defect mass pressure pre-release,the pressure was decreased and migratied efficiently,the coal mining face didnt appear the phenomenon of stress accumulation.

The Paleogene strata from the Bohai area,which consist of the Kongdian,Shahejie and Dongying formations in ascending order,have been divided into members and sub-menbers based on microfossil and 3-D seismic dada.These stratigraphic units and sub-units can be correlated with equivalent strata in adjacent oil and gas fields.The depositional environments and climatic conditions can be inferred from the ecologic features and distributions of microfossils and lithologic characteristics.Such environmental conditions also control the formation and distribution of stratigraphic units and sub-units that contian oil source beds and reservoirs.The present research on the characteristics of the Paleogene microfossil assemblages from the Bohai area has important significance on oil and gas exploration.

SZ36-A oilfield is a big oilfield with hundred-million tons in Bohai offshore field. The mainly oil-bearing is concentrate on Paleogene Ed2 formation. Through integrating theory with practice, geophysical with geological, reservoir characteristics with sedimentary facies and exploration with development, the rules of reservoir microscopic characteristics and its main controlling factors have been analyzed in this paper. The favorable reservoirs are mainly distributed in lake delta front. At the same time, diagenesis has been analyzed, which calculates the relative of clay minerals component temperature and pressure fields, liquid's filling and other important effects on reservoir characteristics. The sets of reservoir extension have bigger thickness, which belongs to high porosity and high permeability favorable reservoirs.

Based on the study of petrology、paleontological and seismic stratigraphy,in this paper we detail methods of using drilling、 seismic data to establish Lithology,electricity character contrast relations;to establish paleontology assemblage distinguishing characteristics;to sum up different paleogeographic evolution's effect on biostratigraphy;to recognize the rule of seismic reflection characteristics and 3D spatial change in study block.At the same time,we discuss the relationship of stratum and hydrocarbon distribution,in the end,we solve the problems which have arisen in the exploration and the results provide guidance for oil and gas exploration.

The waveform analysis of seismic facies can be a good solution to the prediction of the sand body problems. Previous researches and applications of waveform seismic facies in oil exploration mostly include the depositional and provenance systems; the relationship was not established between lithologic characteristics and waveforms. This article tries to establish the links between lithologic and seismic waveform in the context of shallowwater delta deposits. Any change in physical parameters of seismic signal is always reflected in changes of seismic waveform. Seismic facies classification processing is based on reflection changes in waveform through self-organizing neural network algorithms. First, the algorithm obtains the model trace and utilizes the shape of seismic trace (i.e. wave characteristic) to contrast the actual seismic data in the layer interval and then describe the lateral variation of seismic signal.

According to the geological conditions of tectonic type closed distance seam group,established a mechanical model for the buckling failure of floor gas drainage roadways in tectonic type of closed distance seam group.Obtained the conclusion by calculation:the deformation of roof and floor in roadway obviously increases when the axial pressure of roof and floor in roadway being 0.8 times of the minimum axial pressure will make beam to be buckling failure;the deformation of roof and floor causes compressive failure of the roadway's sides;the development of the deformation of surrounding rocks and the transfer of abutment pressure is closely related.Combined with mechanics analysis,theoretic research,the surrounding wall of mines and conditions of mining environment,put forward the control mechanism and new support technology of floor gas drainage roadways which is the gas channels that the gas pass by fractures made by dynamical pressure of bottom coal mining,determined the relative distance of two faces' roadway of closed distance seam group is 35 m,reached the requirement of gas stereo drainage between roadway excavation and working face mining of closed distance seam group,so the new technology can control the concentration of gas,achieve the mining safety and ensure the consumption of civil gas.

The sequence stratigraphy of the Guantao Formation was investigated by integrating lithostratigraphic,well log,paleontological,and seismic stratigraphic data.Three system tracts,LST(low-stand system tract),TST(transgressive system tract)and HST(high-stand system tract)were recognized.Base on base-level cycle analysis,three kind of base-level cycles(SSC:short-term baselevel cycle sequence;MSC:medium-term baselevel cycle sequence;and LSC:long-term baselevel cycle sequence)in Guantao Formation were recognized.The Guantao Formation is divided into two LSCs and four MSCs(MSC1 to MSC4).The depth of 2782 to 2917 meter of the D5-1 well belongs to the Dongying Formation,whose upper boundary marks the base of the Guantao Formation.Ascertaining the lower boundary of the Guantao Formation and a detailed sequence stratigraphic investigation of the Dongying Formation provide important stratigraphic basis to support the oil and gas exploration in the middle Bohai Bay Basin.

The complex tectonic background of the Bohai Basin during the deposition of the member 4 of the Shahejie Formation(Sha-4 Member)means that this stratigraphic unit is spatially complex and variable.At its type section in the Jiyang Depression,the member 4 can be divided into the upper,middle and lower sub-members.With increasing borehole data and further investigation,our understanding of the member 4 of the Shahejie Formation has been improved.In the past,the member 4 was not subdivided into submembers and it was recognized as two types in the southern and northern Bohai Basin.With new data and complete successions,the member 4 in the Bohai Basin can be divided into,we can now divide this member into the upper and lower sub-members,which were deposited in very different conditions.The lower sub-member is characterized by evaporitic lacustrine deposits,whereas the upper sub-member is characterized by sandy mudstones.Drill holes in the southern Bohai Basin have penetrated the entire Member 4,whereas drill holes in the northern Bohai Basin only penetrated the upper sub-member and the lower sub-member is probably missing.Regardless,the lithostratigraphy of the Member 4 is comparable in the southern and northern Bohai Basin.The lower sub-member 4 in the Bohai Basin can be correlated with the upper and lower sub-members in the Jiyang Depression.The lower sub-member in the Bohai Basin is not an ideal target for petroleum exploration,whereas the upper sub-member has a suite of cource-reservoir-cap rocks and should be a exploration target.

By researching on the sequence stratigraphy based on the lithology characteristics,electrical characteristics,paleontology,seismic sequence stratigraphy and the study of areal geology,this paper is trying to obtain much deeper recognition of the Guantao Formation stratigraphy.Three kinds of tracts were recognized including LST,TST and HST.Based on basal level cycle technique,three kind of base-level cycles(SSC,MSC and LSC) were recognized in Guantao Formation.Guantao Formation was divided into two LSC and four MSC,and high resolution isochronous geologic correlation of Guantao Formation and upper Donying Formation.Interval from 2 782 m to 2 917 m of D5-1 well is upper Dongying Formation,and the top of this interval is the bottom of Guantao Formation.

As a special type of reservoir,the volcanic reservoirs are bringing to people's attention gradually,while prediction and identification methods of volcanic rocks at drilling site are also becoming the focal points which the people pay attention to. Based on making analysis of the regional geologic background,the surrounding offset wells,the seismic reflectance signature,the seismic attributes and the other data of Kenli area in Bohai marine area,the prediction methods of volcanic rocks were discussed. On this basis,combining with the cases study of the encountered volcanic rock from well KL 6-A-1,the response characteristics of mud logging and wireline logging were respectively talked over,the identification means and methods were defined,which are adapt to the encountered volcanic rocks in KL 6-A block. The initial applied results indicated the prediction and identification methods are not only applicable to Kenli area of Bohai marine area,but also have reference functions for predicting and field identifying the volcanic rocks of other areas of Bohai marine area.

In the southwest of Sichuan, Upper Permian Formation, the thickness of Emeishan basalts of Zhougongshan and its neighbor area is from 40m to 500m,and it is formed by 12 cyclic basaltic volcanic rock. The volcanic breccias in the bottom and the stomatal basalts in the upper have some reservoir capability in cyclicity. The reservoir spaces mainly are air voids,basaltia jointing split and tectoclase. Generally, they form lower porosities, medium permeability or lower porosities,higher permeability reservoirs. In other sections, if there are not the superposition of tectonic movement,most of them can not form reservoir rocks,during the formation and evolution of this set of reservoirs, the condensation contract fissure of magmatic melt,tectonic rupture,organic maturation and chemical erosion. All of these have promoted the forming of reservoir spaces. But hydrothermal alterations and 4 stage cementation and 3 stage packing action have obvious damage affection to reservoir spaces.