This session focusses on two topics.
One purpose is to promote discussions between scientists who use data to address problems and the scientists who are developing new measurement technologies and methods for application in the diverse geoscientific areas, from sediment to hard rock settings, structural analysis of deformation, fracture and porosity, determination of rock physical properties, pore fluid analysis, rock stress and fluid pressure determinations. Subjects of interest include slimhole techniques, underbalanced, ice and gas hydrate drilling and logging, low environmental impact tools, high pressure and temperature tools, logging in high-angle/horizontal wells, formation evaluation in conventional and non-conventional plays, measurements in tunnels, non-conventional applications of classical logs, and underground lab facilities like boreholes for testing and test installations in mines.

The other focus aims to present the latest results in the investigation of complex karst phenomena by application of various geophysical integrations in any possible variants (surface, subsurface, borehole, remote operate vehicles, airborne and satellite) using various advanced algorithms and software enabling karst (sinkhole) detection, visualization and contouring as well as geophysical model simulations.Subsurface carbonate rocks involved in karst groundwater circulation considerably extend the active karst realm, to perhaps 14% of the worls land area. Active sinkholes growth appears under different industrial constructions, roads, railways, bridges, airports, buildings, etc. The total annual economic damage from the karst phenomena in the world is estimated as 30 billion US $. Subsurface in many regions of the world is characterized by high variability of physical properties both on lateral and vertical that complicates geophysical surveys acquisition and analysis. Some typical problems cause physical properties limitations (e.g., very low resistivity in some arid regions limits employment of such methods as GPR and VLF, in other regions small magnetic properties contract hampers magnetic survey employment, etc.). Therefore, for reliable delineation of karst phenomenon and its monitoring an integration of different geophysical methods should be applied.

This session is merged from the originally proposed sessions GI3.2: 'Instruments and methods for downhole and hazardous environments' and GI3.7: 'Integrated geophysical examination of karst phenomenon in complex environments'.