Observational-computational 3D Engineering Geological Model and GeotechnicalCharacteristics of Young Sediments of Golestan Province

Recently, a number of subsurface investigations have increased as a result of infrastructureconstruction in Golestan province, north of Iran. Although there had been investigations onthe geotechnical characteristics of the subsoils, understanding soil properties and 3Dmodelling of geological structures of the area subsoils have not yet been studied. This paperaims to conduct a 3D engineering geological modelling by means of boreholes data andcomputed geotechnical properties. Due to the lack of data and population concentration,geological model were drawn for Gorgan and Gonbad-e-Kavoos cities which are the biggestcities of the province. The result of these models showed that subsoil of both districts ismainly composed of low plasticity clay (CL) with interbed or lenses of coarse grain sandyand gravely soils. From sedimentological standpoint, it could be inferred that depositionalenvironment of Gorgan city is alluvial fan created by Ziarat River and Gonbad-e-Kavoos islocated on flood plain of Gharasoo River. Since the Golestan province subsoil is mostlyconsist of clayey soil, the geotechnical properties of the Golestan clay such as physicalproperties and engineering properties have been studied in this paper. Finally, geotechnicalhazards associated with these sediments including excavation problems, low bearingcapacity, settlement problems and liquefaction potential were reported

Keywords:

Golestan province , Engineering geologicalmodel , Geotechnical characteristics , Geotechnical hazard