CAJ | 학술논문

流经土洞或岩溶塌陷坑中的地下水破坏了土层的固-液界面离子双电层扩散区中正、负电荷的平衡，引起地下介质(土层)自然极化，形成自上而下的自然电场。土洞或岩溶塌陷在平面上产生自然电位似同心圆负心异常、在剖面上引起极小值异常；自然电位梯度在剖面上出现过零点异常，在平面上呈以零值线为对称轴的正负对称的似“蝴蝶状”异常。岩溶区自然电场法干扰因素主要有工业游散电流等人文干扰电磁场、地下金属管道(线)自然极化电场、上升或下降泉自然电场、山地电场、炭质灰岩自然电场等。针对岩溶区自然电场法干扰因素特点，本文提出采用避让法、排除法、在线监测法进行消除，并将之应用于广西来宾市吉利村岩溶塌陷探测中。结果表明，自然电位剖面曲线在地面沉陷区中心附近出现极小值异常，自然电位梯度剖面曲线也在相同部位显示过零点异常。水文地质监测钻孔在相应的位置上分别揭露了塌陷堆积物、溶洞和断层破碎带，从而验证了上述自然电场法异常的属性。
류경토동혹암용탑함갱중적지하수파배료토층적고-액계면리자쌍전층확산구중정、부전하적평형，인기지하개질(토층)자연겁화，형성자상이하적자연전장。토동혹암용탑함재평면상산생자연전위사동심원부심이상、재부면상인기겁소치이상；자연전위제도재부면상출현과영점이상，재평면상정이령치선위대칭축적정부대칭적사“호접상”이상。암용구자연전장법간우인소주요유공업유산전류등인문간우전자장、지하금속관도(선)자연겁화전장、상승혹하강천자연전장、산지전장、탄질회암자연전장등。침대암용구자연전장법간우인소특점，본문제출채용피양법、배제법、재선감측법진행소제，병장지응용우엄서래빈시길리촌암용탑함탐측중。결과표명，자연전위부면곡선재지면침함구중심부근출현겁소치이상，자연전위제도부면곡선야재상동부위현시과영점이상。수문지질감측찬공재상응적위치상분별게로료탑함퇴적물、용동화단층파쇄대，종이험증료상술자연전장법이상적속성。
The groundwater that flowing through soil cave or karst collapse pit destroys the balance of posi-tive and negative charges in the ion double electrode layer between the solid-liquid interface in soil,which induces spontaneous polarization of underground medium (soil layer)and forms downward natural electric field.The soil cave and karst collapse cause self-potential negative anomaly that looks like concentric ring in the plane view and cause minimum value anomaly in the profile.The self-potential gradient appears zero crossing point anomaly in the profile and appears "butterfly-shaped" anomaly that is negative-positive sym-metrical in relation to the symmetry axis of zero value line in the plane.The main interference factors of nat-ural electric field in karst region are industrial stray currents,spontaneous polarization electric fields coming from underground metal pipe/line,natural electric fields produced by ascending springs or descending spring,mountain potential fields and natural electric fields of Carbonaceous limestone,etc.According to the characteristics of the interference factors led by self-potential in karst area,avoiding method,eliminating method and online monitoring method are put forth in the paper in order to eliminate the interference factor. The self-potential method has been successfully applied in the karst collapse area in Jili Village,Laibin City, Guangxi.The collapse is located inside the Guilin-Laibin fault zone and on the sides of the Datoushan syn-cline axis of the secondary fold between the transition zone of the east limb of the Pingtang anticline and the west limb of the Laibin syncline.The landforms there are characterized of karst accumulation and residual peak pimple plain.The overlying layers are gravel silty clays of the Quaternary eluvial and slope-alluvia,the underling rocks are mainly thick bedded limestone with dolomitic limestone interlayer of the Middle Carbon-iferous (C2 ).A set of NNE trending fault develops parallel to the fold axis accompanied by a group of the NWW trending tension-shear fault in the nearly vertical fault direction which cuts and offsets the main NNE faults.The broken rocks and karst features as well as karst collapse are widely spread and quite developed in fault fracture zones.The actual measured self-potential curve has minimum value anomaly around the center of the subsidence area.At the same position the self-potential gradient profile has zero value anomaly.Verti-cal fissures on the ground are quite developed.And the fissures in the abnormal regions detested by self-po-tential method are consistent with the trend of the conjectural fault fracture zones and the direction of the un-derground river.Collapse deposits,caves and fault fracture zones are exposed at the same position by hydrogeologic monitoring borehole,which verifies the properties of self-potential anomalies have been discussed above.