In Situ Stress Measurements in the Lhasa Terrane,Tibetan Plateau,China

the India and Eurasia plates. Knowledge of the stress state is critical to evaluate the crustal stability and the design of underground excavations. Because of the limitations imposed by natural conditions, little research has been performed on the present crustal in situ stress in the Tibetan Plateau, and further study is imperative. In this study, hydraulic fracturing measurements were conducted in Nyching County （LZX） and Lang County （LX）, Lhasa terrane to characterize the shallow crustal stress state. The results indicate that the stress state in the LZX borehole is markedly different from that in the LX borehole, in both magnitude and orientation. At the same measurement depths, the magnitudes of horizontal principal stresses in the LX borehole are 1.5–3.0 times larger than those in the LZX borehole. The stress regime in the LX borehole favors reverse faulting characterized by SH〉Sh〉Sv, where SH, Sh, and Sv are maximum horizontal, minimum horizontal, and vertical principal stresses, respectively. The SH and Sh values are approximately three and two times greater than Sv. Fracture impression results reveal that SH in the LX borehole are predominantly N–S, while in the LZX borehole the maximum horizontal principal stress is mainly in the NNE-direction. The heterogeneity of the regional stress state might be a result of the population and distribution of local structures and seismic activities. The stress state in the LX borehole has exceeded the critical state of failure equilibrium, and there is an optimally orientated pre-existing fault near the borehole. It can be concluded that the optimally orientated fault is likely to be active when the stress has built up sufficiently to destroy the frictional equilibrium; it is suggested that research focus should be placed on this in future. The stress states in boreholes LZX and LX indicate uniformity of the regional stress field and diversity of the local stress fields resulting from the interactions among regional dynamic forces, tectonic stress field, and geological structures.

Mutual impact of true triaxial stress, borehole orientation and bedding inclination on laboratory hydraulic fracturing of Lushan shale

Unconventional resources like shale gas has been the focus of intense research and development for two decades. Apart from intrinsic geologic factors that control the gas shale productivity (e.g. organic matter content, bedding planes, natural fractures, porosity and stress regime among others), external factors like wellbore orientation and stimulation design play a role. In this study, we present a series of true triaxial hydraulic fracturing experiments conducted on Lushan shale to investigate the interplay of internal factors (bedding, natural fractures and in situ stress) and external factors (wellbore orientation) on the growth process of fracture networks in cubic specimens of 200 mm in length. We observe relatively low breakdown pressure and fracture propagation pressure as the wellbore orientation and/or the maximum in situ stress is subparallel to the shale bedding plane. The wellbore orientation has a more prominent effect on the breakdown pressure, but its effect is tapered with increasing angle of bedding inclination. The shale breakdown is followed by an abrupt response in sample displacement, which reflects the stimulated fracture volume. Based on fluid tracer analysis, the morphology of hydraulic fractures (HF) is divided into four categories. Among the categories, activation of bedding planes (bedding failure, BF) and natural fractures (NF) significantly increase bifurcation and fractured areas. Under the same stress regime, a horizontal wellbore is more favorable to enhance the complexity of hydraulic fracture networks. This is attributed to the relatively large surface area in contact with the bedding plane for the horizontal borehole compared to the case with a vertical wellbore. These findings provide important references for hydraulic fracturing design in shale reservoirs.

New development of hydraulic fracturing technique for in-situ stress measurement at great depth of mines

In-situ stress measurement using the hydraulic fracturing technique was made at Wanfu Coal Mine in Shandong Province, China. To solve problems caused by great measuring depth and extra thick overburden soil layers in the mine, a series of improved techniques were developed for the traditional hydraulic fracturing technique and equipment to increase their pressure-enduring ability and to ensure safe and flexible removal of the sealing packers with other experimental apparatus. Successful in-situ stress measurement at 37 points within 7 boreholes, which were mostly over 1000 m deep, was completed. Through the measurement, detailed information of in-situ stress state has been provided for mining design of the mine. The improved hydraulic fracturing technique and equipment also provide reliable tools for in-situ stress measurement at great depth of other mines.

Extended finite element-based cohesive zone method for modeling simultaneous hydraulic fracture height growth in layered reservoirs

In this study,a fully coupled hydromechanical model within the extended finite element method(XFEM)-based cohesive zone method(CZM)is employed to investigate the simultaneous height growth behavior of multi-cluster hydraulic fractures in layered porous reservoirs with modulus contrast.The coupled hydromechanical model is first verified against an analytical solution and a laboratory experiment.Then,the fracture geometry(e.g.height,aperture,and area)and fluid pressure evolutions of multiple hydraulic fractures placed in a porous reservoir interbedded with alternating stiff and soft layers are investigated using the model.The stress and pore pressure distributions within the layered reservoir during fluid injection are also presented.The simulation results reveal that stress umbrellas are easily to form among multiple hydraulic fractures’tips when propagating in soft layers,which impedes the simultaneous height growth.It is also observed that the impediment effect of soft layer is much more significant in the fractures suppressed by the preferential growth of adjoining fractures.After that,the combined effect of in situ stress ratio and fracturing spacing on the multi-fracture height growth is presented,and the results elucidate the influence of in situ stress ratio on the height growth behavior depending on the fracture spacing.Finally,it is found that the inclusion of soft layers changes the aperture distribution of outmost and interior hydraulic fractures.The results obtained from this study may provide some insights on the understanding of hydraulic fracture height containment observed in filed.

Hydraulic Fracturing Stress Measurements and Their Implication for the Design of the First Concrete Lined Pressure Shaft in Sri Lanka

The Urea Oya Multipurpose Development Project （UMDP） is a water transfer, hydropower and irrigation in the south-eastern part of the central highland region of Sri Lanka. During geotechnical site investigation program 42 hydraulic fracture tests and 42 impression packer tests were carried out in 3 boreholes to about 840 m depth. Based on the stress measurements the minimum and maximum horizontal stress ratios were calculated. In situ stress computations at all the tests were based on the assumption that the principal stress components were vertical （σv） and horizontal （σH and σh, the maximum and minimum, respectively）. The results of the measurements had a direct impact on the design of the major openings bearing a high overburden--the underground powerhouse and the transformer cavern--and revealed a significant optimization potential concerning the selection of the lining system of the pressure shaft.

Rock Stress Measurement Methods in Rock Mechanics—A Brief Overview

The current brief review paper on rock stress measurement methods is very crucial factors in mining, civil infrastructure, geothermal energy, nuclear underground disposal, large underground oil storage caverns, etc as well as in geology and geophysical area. Measurement of in situ rock stress is a very challenging and difficult quantity and not possible to measure directly. Measure the deformation or displacements or hydraulic factors by perturbing the rock and converting the measured quantity into rock stress. There are two main categories for measuring methods: direct and indirect methods. The most common methods of direct in situ stress techniques are briefly described including advantages, disadvantages and limitations. Moreover, authors included the application of Artificial Intelligence (AI) for rock stress measurement methods.

Characteristics of in-situ stress and its controls on coalbed methane development in the southeastern Qinshui Basin,North China

In-situ stress is a key reservoir parameter to evaluate reservoir permeability,hydraulic fractures,coal seam deformation and coalbed methane(CBM)recovery.With limited CBM test wells in the Zhengzhuang field,southeast of the Qinshui basin,North China,the in-situ stress data is inadequate for CBM exploration and development.It is necessary to find a method to predicate in-situ stress through other exploration data such as geophysical well loggings.In this study,we provide a new well-logging databased model to predicate the in-situ stress based on 17 sets of well test data and comprehensive logging data.As a distinguished characteristic of this model,different structural compartmentalization of CBM reservoirs was considered.A regional adaptive residual strain index was introduced to the model.Based on the model,the in-situ stress distribution in the Zhengzhuang field were evaluated systematically,and the influences of in-situ stress on permeability and the propagation of hydro-fractures were discussed.Results indicate that the magnitude of the maximum(S_(Hmax),14.19e45.40 MPa)and minimum horizontal stresses(Shmin,10.62e28.38 MPa)and the gravitational stress(Sv,9.58e30.82 MPa)all show positive correlations with burial depths.The in-situ stress fields in the study area are characterized by 1)SHmax>Sv>Shmin in shallow layers(<700 m),indicating a dominant strike-slip faulting stress regime;2)Sv z S_(Hmax)>S_(hmin)and S_(Hmax)>Sv>S_(hmin)in the depth of 700e1050 m,suggesting a transformed regime;and 3)S_(Hmax)>Sv>S_(hmin)in deep layers(>1050 m),indicating a strike-slip faulting stress regime.The S_(Hmax)in the study area is orientated by NE-SW,with a trend of 40e49.Resulted from the change of the in-situ stress regimes from shallow(500 m)to deep layers(~1000 m),the reservoir permeability variation shows a typical increase followed by decrease.The presence of natural fractures significantly affect the propagation pattern of hydraulic fractures,and the length difference between the major and branch fractures increases with increasing stress anisotropy in the Zhengzhuang field.

Preliminary Results of In-situ Stress Measurements along the Longmenshan Fault Zone after the Wenchuan M_s 8.0 Earthquake

Four months after the Wenchuan Ms 8 earthquake in western Sichuan, China, in situ stress measurements were carried out along the Longmenshan fault zone with the purpose of obtaining stress parameters for earthquake hazard assessment. In-situ stresses were measured in three new boreholes by using overcoring with the piezomagnetic stress gauges for shallow depths and hydraulic fracturing for lower depths. The maximum horizontal stress in shallow depths （-20 m） is about 4.3 MPa, oriented N19°E, in the epicenter area at Yingxiu Town, about 9.7 MPa, oriented N51°W, at Baoxing County in the southwestern Longmenshan range, and about 2.6 MPa, oriented N39°E, near Kangding in the southernmost zone of the Longmenshan range. Hydraulic fracturing at borehole depths from 100 to 400 m shows a tendency towards increasing stress with depth. A comparison with the results measured before the Wenchuan earthquake along the Longmenshan zone and in the Tibetan Plateau demonstrates that the stress level remains relatively high in the southwestern segment of the Longmenshan range, and is still moderate in the epicenter zone. These results provide a key appraisal for future assessment of earthquake hazards of the Longmenshan fault zone and the aftershock occurrences of the Wenchuan earthquake.

Measurement and study of the distributing law of in-situ stresses in rock mass at great depth

To solve the technical cruxes of the conventional system in deep rock mass, an automatic testing system for hydraulic fracturing that includes a single tube for hydraulic loop, a pressure-relief valve, central-tubeless packers, and a multichannel real-time data acquisition system was used for in-situ stresses measurement at great depths （over 1000 m） in a coalfield in Juye of Northern China. The values and orientations of horizontal principal stresses were determined by the new system. The virgin stress field and its distributing law were decided by the linear regression from the logged 37 points in seven boreholes. Besides, the typical boreholes arranged in both the adjacent zone and far away zone of the faults were analyzed, respectively. The results show that a stress concentration phenomenon and a deflection in the orientation of the maximal horizontal stress exist in the adjacent zone of the faults, which further provides theoretical basis for design and optimization of mining.

A hydraulic fracture height mathematical model considering the influence of plastic region at fracture tip

To predict fracture height in hydraulic fracturing, we developed and solved a hydraulic fracture height mathematical model aiming at high stress and multi-layered complex formations based on studying the effect of plastic region generated by stress concentration at fracture tip on the growth of fracture height. Moreover, we compared the results from this model with results from two other fracture height prediction models(MFEH, Frac Pro) to verify the accuracy of the model. Sensitivity analysis by case computation of the model shows that the hydraulic fracture growth in ladder pattern, and the larger the fracture height, the more obvious the ladder growth pattern is. Fracture height growth is mainly influenced by the in-situ stresses. Fracture toughness of rock can prohibit the growth of fracture height to some extent. Moreover, the increase of fracturing fluid density can facilitate the propagation of the lower fracture tip.

超深勘察钻孔ASR法地应力测试技术应用

宝灵山隧道是某铁路先开段的重难点控制性工程,其中宝灵山DZ-06勘察钻孔深2118.00 m,是该段深度最大的控制性勘察钻孔。在钻孔的2072.53、2084.27 m深度选取合适岩心,采用ASR法(非弹性应变恢复法)开展了地应力测试,并与该钻孔采用水压致裂法获取的地应力结果进行对比,同时验证了ASR法对于估测超深钻孔的三维地应力大小和方向的实用价值。结果表明:在钻孔2072.53~2084.27 m深度范围,ASR法2个测点获取的最大主应力、中间主应力、最小主应力平均值分别为59.70、54.03、30.74 MPa,最大主应力近水平,方向近SN向,说明该区域以水平构造应力为主;ASR法的最大主应力测试结果均值与水压致裂法测试结果回归值一致性很好,最小主应力测试结果均值与水压致裂法测试结果回归值的一致性处于合理范围,两种方法的水平主应力方向测试结果基本一致。

雅鲁藏布江断裂带东段现今地应力测量与断层活动性分析

为获取位于雅鲁藏布江断裂带东段加查县新建水电站工程场区的地应力状态,探讨雅鲁藏布江断裂带东段活动性,采用自主研发的新一代水压致裂地应力测试技术,实测获取了工程场区的地应力状态,并在收集雅鲁藏布江断裂带沿线地应力数据基础上,结合摩尔-库仑破裂准则,对其断层活动性进行了探讨。结果表明:(1)在工程厂区内122.75~418.75 m深度,实测最大水平主应力SH介于6.07~37.62MPa之间,最小水平主应力Sh介于3.13~20.33MPa之间,最大水平主应力优势方向为北北东向;(2)主应力关系总体表现为SH>Sh>Sv(Sv为垂向主应力),应力结构有利于逆断层的孕育和活动;(3)实测及收集的大部分数据应力莫尔圆与摩擦系数为0.6的破坏临界线相交,表明整体上雅鲁藏布江断裂带东段发生滑动失稳的风险较高,其中西侧贡嘎至朗县一带风险高于东侧林芝地区。

页岩气井地质工程套管变形类型及影响因素研究进展

通过调研国内外大量页岩气井套管变形方面的文献,总结了页岩气井套管变形的类型,探讨了深、浅层页岩气套管变形影响因素差异及面临的问题,并提出了针对性的防治措施及下一步主要研究方向。研究结果表明:(1)页岩气井套管变形类型主要包括挤压缩径变形和剪切变形,深层页岩气井出现套管变形的概率较中浅层更大,主要为剪切变形。(2)造成套管变形的工程因素包括井筒降温、固井质量、套管疲劳、套管质量以及井眼狗腿度等,地质因素包括岩石力学特性、非均匀地应力以及天然裂缝/断层滑移等;深层页岩气井套管变形主要受天然裂缝/断层滑移的影响。(3)页岩气井套管变形风险防治措施包括控制井筒温度及注入强度,采用水泥环力学性能参数较低的水泥进行固井作业,适当减小套管外径、增大壁厚、提升钢级等提高套管质量,以及尽量让井轨迹平滑等;对深层页岩气井可通过将井眼水平段延伸方向与岩层层理方向设计为一致,掌握裂缝分布情况、尽量避开高风险剪切滑移层段,对不同级别滑移风险层段合理降低压裂规模、调整井筒方位等措施来降低套管剪切变形的风险。(4)页岩气井套管变形防治研究方向主要包括优选岩石力学特性好的压裂层段、最优井轨迹与地应力的关系分析、裂缝识别与评价、断层滑移量与套变量计算等方面。

天然裂缝对水力压裂煤的起裂及扩展试验研究

水力压裂是提高低渗透高瓦斯煤层抽采效率和瓦斯产量的有效方法之一。由于煤层中存在丰富的天然裂缝,天然裂缝与水力裂缝相互作用会使水力裂缝的起裂和扩展形式呈现出复杂多样性,从而影响煤层的增透效果。为研究水力压裂煤在天然裂缝作用下的起裂和扩展规律,利用自主研发的多功能真三轴流固耦合试验系统开展了煤的水力压裂试验。基于“孔壁应力集中诱发拉伸破裂”理论研究了水力压裂煤的裂缝起裂规律,并结合断裂力学从细观角度揭示了水力压裂煤的裂缝扩展机制。研究结果表明:天然裂缝的存在会诱导水力裂缝沿着天然裂缝方向扩展,极大降低了煤岩的起裂压力。不含明显天然裂缝煤岩压裂所需的起裂压力与根据拉伸破坏起裂准则计算的理论起裂压力结果相近,符合“孔壁应力集中诱发拉伸破裂”准则;含明显天然裂缝煤岩压裂所需的起裂压力均小于根据拉伸破坏起裂准则计算的理论起裂压力,且当天然裂缝方向垂直于最小主应力方向时,所需的起裂压力较小,为3.355 MPa;当天然裂缝平行于最小主应力时,所需的起裂压力仅大于最小主应力,为7.902 MPa。水力裂缝类型为I型时,不含明显天然裂缝煤岩的实测最小和最大扩展压力值均大于理论计算最小和最大扩展压力值,差值范围分别为2.043~6.845 MPa和3.951~8.576 MPa;当煤岩含明显天然裂缝且天然裂缝方向平行于X方向时,水平应力差的存在将引起煤岩的实测扩展压力值小于理论计算的扩展压力值。水力裂缝类型为Ⅱ型或I-Ⅱ型时,随着水力裂缝长度的增加,裂缝扩展所需压力逐渐减小。

柿庄南区块煤储层地应力和破裂压力特征及其耦合关系

以柿庄南区块112口煤层气井为研究对象,采用水力压裂法计算煤储层地应力,获取了研究区地应力及破裂压力展布特征,分别建立了破裂压力与水平主应力、有效应力之间的相关模型,揭示了该区块3号煤储层地应力与破裂压力之间的耦合关系,并剖析了地应力对破裂压力的影响。研究结果表明:柿庄南区块3号煤储层整体为中等至高应力区,地应力场类型在垂向上发生转换,埋深400~640 m区域以逆断层应力场型为主,640~810 m区域以走滑断层应力场型为主,810 m以深区域以正断层应力场型为主;侧压系数一般为0.38~1.99,埋深600 m以浅区域,绝大多数大于1,埋深600~800 m区域,侧压系数为0.52~1.93,埋深800 m以深区域,侧压系数均小于1;该区块破裂压力为12.89~36.10 MPa,破裂压力梯度为1.47~6.09 MPa/hm,破裂压力与埋深呈现反“S”形变化,810 m以浅破裂压力离散性较大,整体与埋深呈现负相关,810 m以深破裂压力与埋深呈现正相关;该区块最大水平主应力、最小水平主应力及其各自应力梯度与煤储层破裂压力在一定程度上呈现正相关,但相关性不强;同一埋深条件下,破裂压力随着水平主应力的变化而变化,但最小水平主应力对破裂压力的影响明显大于最大水平主应力;煤储层破裂压力与水平主应力差呈反“N”形变化,与有效应力呈正相关;在水平应力差为2~4MPa时,破裂压力随应力差的增大而减小;在水平应力差为4~8 MPa时,破裂压力随应力差的增大而增大;当水平应力差高于8 MPa时,破裂压力随应力差的增大而减小。

自然崩落法矿山矿岩赋存特征精细调查与辅助致裂崩落效果研究

自然崩落法采矿技术对矿岩赋存特征要求严苛,矿岩崩落特性直接影响自然崩落法矿山矿岩崩落速率及出矿块度。通过人工辅助致裂增加矿岩体内部裂隙发育程度实现矿岩预处理,是当前国外自然崩落法矿山生产过程的重要技术手段。本文以我国首座自然崩落法矿山铜矿峪矿向深部转移首采区开采工程为背景,开展了矿岩赋存特征精细调查与水压致裂矿岩预处理试验研究。结果表明:铜矿峪矿410 m中段5号矿体首采区矿岩坚硬、中等完整~较完整,岩体质量等级为Ⅱ~Ⅲ类,矿岩中等可崩~难崩,矿岩崩落破碎特性为中等破碎~大块较多;岩体赋存特征精细调查对于深入了解矿岩崩落特性意义重大;通过钻孔摄像技术获取了水压致裂矿岩预处理试验前后钻孔孔壁图像并揭示了水压致裂过程产生的新裂隙,有效改善了矿岩结构面发育程度;通过对崩落顶板监测及出矿口块度统计分析显示首采区生产期崩落速率提高了3倍多、出矿口大块率降低了58.3%,为铜矿峪矿转深部开采过渡期产能平稳衔接提供了坚实保障;初步形成了水压致裂矿岩预处理技术及装备体系,可支撑我国现代自然崩落法采矿技术进一步推广应用。

枣泉煤矿五分区地应力测试及其分布规律研究

为了获取枣泉煤矿五分区地应力分布规律,采用水压致裂法对原岩地应力进行了现场测试。结果表明:5个测点中最大水平主应力最大为12.66 MPa,最小为4.96 MPa;最小水平主应力最大为6.08 MPa,最小为2.33 MPa;地应力场类型均为水平主应力场,除测点4外,其余测点各方向应力大小排序均为σ_(H)>σ_(v)>σ_(h);测点1~3的最大水平主应力方向分别为N16.5°W、N30.9°W和N22.3°W,具有较强的一致性,测点4和测点5受褶曲构造影响,最大水平主应力方向为N42.6°E和N24.8°W,向垂直褶曲轴线方向偏转。

岩石组构、地应力与流体黏度对鄂尔多斯盆地长73陆相页岩水力裂缝扩展的影响规律

页岩油是原油增储上产的重要领域。由于储层结构致密、超低渗透,页岩油工业开发需要对储层进行大规模压裂改造。与海相页岩储层相比,鄂尔多斯盆地长7_(3)陆相页岩油储层矿物成分与岩石组构差异较大,力学非均质性较强。陆相页岩油靶层选取和高效压裂改造需要明确页岩力学行为和水力裂缝扩展规律。对长7_(3)陆相页岩进行了原位X-ray CT力学试验和三轴水力压裂试验。分析了岩石组构、地应力差和流体黏度对水力裂缝垂向扩展的影响规律。结果表明,岩石组构对陆相页岩的力学行为和破坏过程有显著影响。陆相页岩水力裂缝的垂向扩展受垂向应力差和流体黏度的共同控制。当垂向应力差较小时,黑色页岩中原生弱面显著抑制了水力裂缝的垂向扩展。随着垂向应力差的增大,黑色页岩裂缝体积呈线性增加趋势,而纹层型页岩裂缝体积呈先增大后减小趋势。增大压裂液黏度可减弱层面的阻碍作用,促进水力裂缝垂向扩展。

综合物探方法在复杂地质条件下公路隧道勘察中的应用

西南部复杂山区的隧道建设对加快我国交通强国的建设具有重要意义,为了查明隧道的地质情况,以保证隧道施工的安全,必须提高公路隧道的勘察精度。为了提高勘察的反演精度,实现精细化解译,本次研究在XX隧道勘察过程中,采用EH4大地电磁测深法、钻孔地球物理测井方法、水压致裂法地应力测试、结合三维立体成图技术,建立了以电磁法为主导的复杂地质条件下公路隧道综合物探模式:①利用三维大地电磁测深法通过横纵断面对比反演结果,圈定异常区域的展布;②利用声波测井和钻孔成果验证异常解释的准确性;③采用水压致裂法地应力测试明确隧道的应力分布和岩爆等级;④利用三维立体成图技术。在标高3500 m以下,共圈定出5个异常区域,异常纵向长度30~60 m不等,最深处约625 m;其中隧道里程K31+620—K31+680处异常横向最大宽度约45 m、里程K33+585—K33+620异常横向宽度最大约85 m。采用综合物探方法准确识别出了隧道穿越区的构造、岩性、不良地质体以及异常的分布范围,从而为隧道的设计提供了依据,并为隧道的后续施工提出了建议,对同类项目具有一定的借鉴意义。

喜马拉雅东构造结北缘通麦—波密段现今地应力场特征研究

喜马拉雅东构造结是青藏高原构造演化研究的关键地区,规划有川藏铁路和雅鲁藏布江下游水电开发等重大工程,受限于地质地理条件,其现今地应力场尚不完全清楚。本文利用水压致裂法地应力数据,研究了东构造结北缘通麦—波密段现今地应力场,探讨了其构造应力环境。结果表明,通麦—波密段实测主应力随深度增加而增大,1100 m深度内SH和S_(h)分别为4.87~32.47 MPa和3.05~20.07 MPa,随深度增加梯度分别为2.49 MPa/100 m和1.61 MPa/100 m,略低于青藏地块和东构造结西缘梯度水平,但地应力状态特征参数表明其水平应力作用强度总体上高于青藏地块;SH优势方向为NEE向(N69.2°±11.5°E),相比NNE—NE向区域主压应力方向表现出明显的顺时针偏转特征;现今地应力场由水平向应力作用主导,400 m以浅应力类型为逆冲型,以深转换为走滑型;水平向差应力和构造差应力在600 m深度以下显著增加,构造差应力最大为12.42 MPa,表明通麦—波密段深部存在相对较强的构造应力作用;库伦摩擦失稳准则分析表明,受地形影响较小的200 m以深实测地应力值总体低于摩擦系数取0.6时理论地应力水平,并且430 m深度以下地应力值总体在摩擦系数取0.2~0.4的理论地应力取值范围内,揭示通麦—波密段现今地壳应力强度尚未达到极限水平,目前处于相对稳定的构造应力环境。最后,讨论了现今地应力场对东构造结北缘重大铁路隧道工程的潜在影响,并提出了应对建议。