ИСТИНА

Sakhalin area is characterized as one of the most problem in Russia. It connects with the amount of sliding phenomena expression. Understanding the reasons and mechanisms of landslides formation gives advantages in their increased activity forecast. It also helps in pos-sible prevention of tragically accidents. Last year’s landslides activation was registered in 36 localities, i.e. 10 were urban and 26 were rural. Landslides in bykovsky mudstones formation are of particular interest as properties of such rock are not fully explored. At present sliding phenomena studying at Sakhalin area connects with the need of safety exploration the oil and gas pipelines. The section of the pipeline system, located in the Dolin-sky and Makarov districts, passes through landslide areas. There take places mud and lique-faction slides with a capacity of 7,5 m and block slides characterized by 10,0 m capacity. That is likely to be hazardous to pipelines. The considered object is situated on the west slope of dividing crest which is undermined by right river Lazovaya inflow. According to the map of seismic zonation GSZ-97, the area seismic hazard is 8 points for the periodicities 500 years – map A. For the times of occurrences 1000 and 5000 years – maps B and C the area seismic hazard is about 9 points. Seismic impulses which are caused by earthquakes are the reasons of sliding processes. The assessment of sliding riskiness was made by impact analysis the sliding processes factors on the stability coefficient’s value of investigated slide. Among factors were considered seis-mic activity, the value of groundwater level as consequence the value of interstitial pressure and strength soil’s properties. Calculations of the stability were made using the Rocscience software. The faculty of engineering geology named in honour of F.P. Savarenski in MGRI-RSGPU is a part of Rocscience Education Program.