Scanning the Earth - a Comprehensive Analysis of Borehole Images and Core Data. Case Study of Vendean Clastic Formation of Eastern Siberia
A. Islamov and N. Belyaeva
Event name: GeoBaikal 2018
Session: Oilfield Geology in East Siberia and Yakutia
Publication date: 11 August 2018
Info: Extended abstract, PDF ( 936.85Kb )
Price: € 20
Vendean clastic formation of Nepsko-Botuobinskaya anticline is one of the most complex reservoirs of East Siberia of Russia. Main uncertainties related to prediction of reservoir rocks by standard well logs and limited predictability of current geological model. By using integrated approach to the analysis of the Core data and Logs, with borehole images (FMI) as tool for this integration, comprehensive analysis performed, including from detailed depth-matching to complex sedimentological analysis of reservoirs. Detailed sedimentological description of Core was improved by adding information of dips and azimuth of interpreted sedimentological surfaces. This information gives us understanding of the direction of paleocurrents which help in facial prediction and reservoir geometry analysis. As a result, flow directions trends within the lower basal part of Vendean section shows strong dependency with existed relief and paleovalleys. In the middle part of lower reservoir image logs confirmed our conception in regional paleoslope direction. Upper part of the lower reservoir shows bimodal reversal directions of cross beds, which gives along with texture features of Core influence of tidal activity of the sea and shift from continental area to transitional zone. Upper reservoir shows very different flow direction from the expected, which can be explained by transformation of territory which is also shows by well-to-well correlation based on sequence stratigraphic principles.