华蓥山区域岩溶水系统及其与龙潭煤系组合关系研究

发布时间：2018-08-18 07:36

【摘要】：华蓥山地区是川东平行岭谷主体山脉,是由一系列近于平行的狭长不对称箱状高背斜组成“隔档式构造”构造山系,为一套寒武纪至三叠纪的碳酸盐岩地层,分布面积987.88km~2,岩溶广泛发育。华蓥山是四川主要产煤区之一,龙潭煤系是主要的产煤层,位于P_1m+q和P_2c岩溶含水层之间,开采难度较大。华蓥山地区现有87处开采龙潭煤系的煤矿,发生多起岩溶涌突水事故。论文运用水文地质调查、地质统计、同位素技术、水文地球化学反向模拟、示踪试验、地球物理勘探等技术手段,以区域地下水系统理论为指导,系统研究了华蓥山地区岩溶含水系统、岩溶水运动系统以及龙潭煤系与岩溶水系统组合特征等,对华蓥山地区龙潭煤系开采具有重要的科学指导意义。取得以下主要成果与结论:(1)区域内可溶岩地层主要有三叠系(T)、二叠系(P)、奥陶系(O)和寒武系(?)等,总面积为987.88km~2;三叠系(T)碳酸盐岩出露面积最广,占总量的80.71%;二叠系(P)碳酸盐岩以灰岩或灰岩夹泥灰岩为主,占总量的16.33%;奥陶系(O)以均匀状灰岩或互层状泥灰岩为主,占总量的1.71%;寒武系(?)以纯质白云岩为主,占总量的1.25%。(2)区内岩溶发育形态丰富,岩溶个体共计2061个;溶蚀洼地633个,高程范围600~1000m内467个,占溶蚀洼地总量的73.78%;落水洞477个,高程范围600~1000m内381个,占落水洞总量的79.87%;溶斗和竖井共计768个,高程范围600~1100m内730个,占溶斗和竖井总量的80.47%;溶洞183个,高程范围400~900m内135个,占溶洞点比例73.77%;地层岩溶发育强度依次为T_1jT_1fP_1m+qP_2c+P_2lO?_(2-3)ls。(3)岩溶介质形态组合划分为纯层管道-裂隙型、夹层管道-裂隙型和裂隙型等3类,纯层管道-裂隙型含水介质主要分布在T_2l、T_1j、T_1f2+4、P_1m+q、O1t+h和?_(2-3)ls含水层,分布面积为872.73km~2,夹层管道-裂隙型主要分布在P_2c、P_2l2+4和O2-3含水层,分布面积为115.15km~2,裂隙型在各岩溶含水层均有分布;岩溶含水岩组分为3个富水等级,强-极强富水岩组分布面积为848.91km~2,中-强富水含水岩组分布面积为133.64km~2,中-弱富水含水岩组分布面积为5.33km~2;岩溶蓄水构造分为背斜型、向斜型和复合型3类,岩溶水主要径流方式为顺轴向流动而形成地下河径流带或“倒虹吸”式垂直轴向径流。(4)区内岩溶水主要补给来源为大气降水和地表水,径流通道以管道和裂隙为主,排泄途径主要为岩溶泉、地下河及人工疏排;岩溶水运动垂向分为表生岩溶带、垂直下渗带、季节交替带、饱水带、压力饱水带和深部缓流带,并划分为单一构造型、复合构造Ⅰ型和复合构造Ⅱ型等3种岩溶水运动垂向分带模式,区内煤矿的风井巷道多位于季节交替带或饱水带,采煤巷道多位于压力饱水带;岩溶水运动模式划分为背斜构造控制和向斜构造控制2大类,6小类;综合岩溶含水结构特征、岩溶水运动特征、水化学特征及循环交替分析、典型岩溶水子系统解剖等,提出华蓥山地区岩溶水系统的概念模型。(5)根据对煤层的充水特征,岩溶含水层分为直接充水含水层和间接充水含水层,前者包括P_1m底板直接充水含水层和P_2l直接顶板充水含水层,后者包括P_2c、T_1f、T_1j和T_2l等含水层,对煤层和井硐威胁最大为P_2c岩溶含水层;煤系赋存形态受华蓥山复式构造的滑脱构造格局控制,形成煤层直立或倒转、重复或缺失、厚度局部变化和破坏煤层连续性等4种赋存形态;煤系与岩溶水系统组合关系分为单斜构造型(Ⅰ型和Ⅱ型)、向斜构造型、断块构造型和复合构造型4类;在龙滩煤矿绘制了P_2c和P_1m含水层天然条件和疏干条件下的岩溶水等水位及流场图,天然条件下的矿区岩溶水运动系统具有层次性,疏干条件下的矿区岩溶水运动系统不断演化,出水点和岩溶泉之间出现次级分水岭,随疏干排水进行,分水岭逐渐外移,岩溶水系统的非统一性增强,分层性减弱或消失。(6)以龙门峡南煤矿突水案例,突水水源判别研究显示回风平硐M1监测点和M2监测点与S3泉点和S5泉点具有一定的水化学相似关系,与T_2投入点具有一定的水力联系,其中M1监测点与S3泉点具有较大的同源性,与T_2投入点具有较大的连通性,径流通道入口和出口均位于P_2c含水层;地下径流通道探测研究发现裂隙密集发育区20处、大型新溶洞5个、导水断层2条,并验证了6#溶洞与+623m回风平硐地下暗河之间的水力联系,划定岩溶发育集中高程为540~660m,多处于P_2c岩溶含水层,具备水力联系。(7)煤矿岩溶突水通道主要为断层带和岩溶导水陷落柱,裂隙是其基本要素,T_1f、P_2c和P_1m地层张裂隙发育,多贯穿上下含水层,对煤系地层充水影响较大;张性断层多为充水和导水断层,突水压力大,原始状态下压扭性断层充水和导水性能较差,在静水压力和矿山压力作用下,闭合型断层可进一步破碎或充填物被冲蚀而转化为可充水和导水断层,结合断层性质归纳断层突水模式;本区域P_2c和P_1m含水层发育大量岩溶陷落柱,具明显的分区性和分带性,P_2c地层岩溶陷落柱是岩溶水的主要径流通道,可贯穿上下含水层,当与冒裂带导通时,可形成突水主要通道;采动条件下煤层底板破坏深度与P_1m地层陷落柱扩展裂隙导通时,也可产生渗水或突水。
[Abstract]:Huayingshan area is the main mountain range of the parallel ridge and valley in eastern Sichuan. It is composed of a series of narrow and asymmetrical box-like anticlines which are close to parallel. It is a set of carbonate strata from Cambrian to Triassic. The area of Huayingshan is 987.88 km~2 and the karst is widely developed. The main coal-producing seams are located between the P_1m+q and P_2c karst aquifers, so it is difficult to exploit them. There are 87 coal mines in Huayingshan area which have exploited Longtan coal measures, and many karst water inrush accidents have occurred. Guided by the theory of regional groundwater system, the karst water system, karst water movement system and the combination characteristics of Longtan coal measures and karst water systems in Huayingshan area are systematically studied, which has important scientific significance for Longtan coal measures mining in Huayingshan area. The strata are mainly Triassic (T), Permian (P), Ordovician (O) and Cambrian (Cambrian), with a total area of 987.88 km~2; Triassic (T) carbonate rocks are the most widespread, accounting for 80.71% of the total; Permian (P) carbonate rocks are mainly limestone or limestone-marl, accounting for 16.33% of the total; Ordovician (O) is mainly homogeneous limestone or interbedded mudstone, accounting for the total. (2) There are 2 061 karst individuals in the area, 633 karst depressions, 467 in the range of 600-1000 m, accounting for 73.78% of the total amount of karst depressions; 477 caves, 381 in the range of 600-1000 m, accounting for 79.87% of the total amount of caverns; There are 768 karst caves, 730 in the range of 600-1100m, accounting for 80.47% of the total karst bucket and shaft; 183 caves, 135 in the range of 400-900m, accounting for 73.77% of the total karst caves; and the formation karst development intensity is T_1jT_1fP_1m+qP_2c+P_2lO? (2-3) ls. (3) The karst medium morphological combination is divided into pure layer pipeline-crack type, interlayer pipeline-crack type and interlayer pipeline-crack type. Fissure-type aquifers are mainly distributed in T_2l, T_1j, T_1f_2+4, P_1m+q, O_1t+h and?(2-3) LS aquifers with an area of 872.73 km~2. Interlayer pipeline-fissure aquifers are mainly distributed in P_2c, P_2l_2+4 and O_2-3 aquifers with an area of 115.15 km~2. It is divided into three water-rich classes, the distribution area of strong-extremely strong water-rich rock group is 848.91 km~2, the distribution area of medium-strong water-rich rock group is 133.64 km~2, and the distribution area of medium-weak water-rich rock group is 5.33 km~2. The karst water storage structure is divided into anticline type, syncline type and composite type. The Main Runoff mode of karst water is along-axis flow and underground river diameter is formed. (4) The main recharge sources of karst water in the area are atmospheric precipitation and surface water, and the runoff channels are mainly pipelines and fissures, and the discharge channels are mainly karst springs, underground rivers and artificial drainage; the vertical movement of karst water is divided into supergene karst zone, vertical infiltration zone, seasonal alternating zone, saturated zone, and pressure saturation zone. Water zone and deep slow flow zone are divided into three vertical zoning modes of karst water movement, i.e. single structural type, composite structural type I and composite structural type II. The air shaft tunnels in the area are mostly located in the seasonal alternating zone or water-saturated zone, and the coal mining tunnels are mostly located in the pressure-saturated zone. The conceptual model of karst water system in Huayingshan area is put forward based on the characteristics of karst water-bearing structure, karst water movement, hydrochemical characteristics and cyclic alternation analysis, and the anatomy of typical karst water subsystems. (5) According to the water-filling characteristics of coal seams, karst aquifers are divided into direct water-filling aquifers and indirect water-filling aquifers. The former includes the P_1m floor water-filled aquifer and the P_2l roof water-filled aquifer, while the latter includes the P_2c, T_1f, T_1j and T_2l aquifers, with the biggest threat to coal seams and caverns being the P_2c karst aquifer; the occurrence form of coal measures is controlled by the slip structure pattern of Huayingshan complex structure, forming the coal seam vertical or inverted, repeated or missing, thickness. There are four kinds of occurrence forms, i.e. local change and destruction of coal seam continuity; the association relationship between coal measures and karst water system can be divided into monoclinic structure type (type I and type II), synclinal structure type, fault block structure type and composite structure type; the water level and flow field maps of P_2c and P_1m aquifers under natural and drainage conditions are drawn in Longtan Coal Mine. The karst water movement system under the condition of drainage is hierarchical, and the karst water movement system under the condition of drainage is evolving continuously, and a secondary watershed appears between the water outlet point and the karst spring. With the drainage proceeding, the watershed gradually moves out, the non-uniformity of the karst water system is strengthened, and the stratification is weakened or disappeared. (6) The water inrush from the South Coal Mine of Longmen Gorge Case study shows that M1 monitoring point and M2 monitoring point of return air tunnel have some similar relationship with S3 spring point and S5 spring point, and have certain hydraulic connection with T 2 input point. M1 monitoring point and S3 spring point have greater homology, and have greater connectivity with T 2 input point, and the inlet and outlet of runoff channel are both. It is located in the P_2c aquifer; the detection and study of underground runoff channel found 20 densely developed fracture areas, 5 large new karst caves and 2 water-conducting faults, and verified the hydraulic relationship between the 6# karst cave and the underground river of the + 623m return air adit, and demarcated the karst development concentrated elevation of 540 ~ 660m, mostly in the P_2c karst aquifer, with hydraulic connection. (7) Coal mine karst. Water inrush channel is mainly fault zone and karst water-conducting subsidence column, fissure is its basic element, T_1f, P_2c and P_1m formation tensile fissure development, mostly through the upper and lower aquifers, water-filling of coal measures formation has a greater impact; Tensional faults are mostly water-filling and water-conducting faults, water inrush pressure is large, the original state of compressive-torsional faults water-filling and conductivity is poor, in static state. Under the action of water pressure and underground pressure, closed faults can be further broken or filled with erosion into water-filling and conducting faults, combined with the nature of faults, water inrush model of faults is summarized; there are a large number of karst subsidence columns in the P_2c and P_1m aquifers in this area, with obvious zoning and zoning, and the karst subsidence columns in P_2c strata are karst water. The Main Runoff channel can penetrate the upper and lower aquifers, and the main channel of water inrush can be formed when it is connected with the caving zone.
【学位授予单位】：成都理工大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：P641.461

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