CAJ | 학술논문

为了预警泥石流的发生，需要判断泥石流的易发程度。在地质和降雨条件都大致相同的条件下，因地形条件的不同，导致一个区域的沟谷暴发泥石流的频率有着明显不同，显然地形条件是控制泥石流发育的关键因素之一。以研究岷江流域上游典型沟谷为例，通过分析地形条件对泥石流发育的影响，选用岷江流域上游典型沟谷的形成区流域面积 A0、形状系数 F0以及沟床纵比降 J03个重要参数进行研究，比较三者相互之间的关系特征而得到一个综合的地形因子 G。对比研究岷江流域典型区域以及甘肃舟曲、台湾陈有兰溪地区沟谷泥石流的暴发频率和G值，比较验证后得出：在地质和降雨条件都相近的情况下，沟谷G值越大，则越利于暴发泥石流。因此，可运用地形因子G划分某区域内沟谷泥石流的易发等级。对于岷江流域典型区域的沟谷：G≥0．21极容易暴发泥石流；0．14＜ G＜0．21较容易暴发泥石流；G≤0．14不容易暴发泥石流。由于地质条件和降雨情况的差异，不同地区泥石流易发等级所对应的G值也将不同。
위료예경니석류적발생，수요판단니석류적역발정도。재지질화강우조건도대치상동적조건하，인지형조건적불동，도치일개구역적구곡폭발니석류적빈솔유착명현불동，현연지형조건시공제니석류발육적관건인소지일。이연구민강류역상유전형구곡위례，통과분석지형조건대니석류발육적영향，선용민강류역상유전형구곡적형성구류역면적 A0、형상계수 F0이급구상종비강 J03개중요삼수진행연구，비교삼자상호지간적관계특정이득도일개종합적지형인자 G。대비연구민강류역전형구역이급감숙주곡、태만진유란계지구구곡니석류적폭발빈솔화G치，비교험증후득출：재지질화강우조건도상근적정황하，구곡G치월대，칙월리우폭발니석류。인차，가운용지형인자G화분모구역내구곡니석류적역발등급。대우민강류역전형구역적구곡：G≥0．21겁용역폭발니석류；0．14＜ G＜0．21교용역폭발니석류；G≤0．14불용역폭발니석류。유우지질조건화강우정황적차이，불동지구니석류역발등급소대응적G치야장불동。
There are three groups of factors related to topography ,geology and hydrology which have influence on the formation of gully type debris flow s .In this study ,a single representative factor (G-factor) for the topography is proposed ,which can be used to give threshold values for debris flow formation .The study was carried out in the upper reaches of Minjiang River ,which is located in the Wenchuan earthquake area .During some rainfall events after the earthquake ,some gully type debris flows were triggered in some catchments .In some catchments no debris flows were triggered even though these catchments were in the vicinity of gullies with triggered debris flows .We isolated and analyzed the influence of the topography on the formation of debris flows because during these rainfall events the hydrological conditions were almost the same in the investigated gullies . We could also neutralize the influence of the geological factors by selecting groups of neighboring catchments located in areas with the same geological characteristics . A new G-factor is proposed in this study as a topographical indicator G ,in w hich F0 is the form factor of formation area , J0 is the average slope of formation area ,A0 is the area of formation area ,and A * is the unit area (=1 km2 ) .Higher G-factor values are generally related to higher probabilities of debris flow formation .The roles of G-factor are analyzed in other areas such as Zhouqu ,Gansu ,and Chenyoulan River Watershed ,Taiwan .It shows that the higher G-factor values ,the higher probabilities of debris flow formation are in generally .In the typical areas of Minjian River areas ,it is very high probabilities of debris flow formation when G≥0 .21 . T he probabilities of debris flow formation is very low w hen G≤0 .14 .