Tuesday 6 October 2015
On wednesday October 14, 2015, ir. Hans de Ruiter will present the KNGMG Staringlezing. The title of the lecture (in Dutch) is ‘De opleiding Mijnbouw ? niet “altijd zoo geweescht”’. The lecture will take place at Science Centre Delft, Mekelzaal, Mijnbouwstraat 120, 2628 RX Delft.
More information can be found here
Sunday 16 August 2015
After serving as webmaster on the PGK board for the last couple of years, Gijs Straathof has decide to step down. Thank you Gijs for your hard work!
Ivo Vos (working at SGS Horizon in Voorburg) will be taking on the board position as webmaster as per August 2015.
lecture · drinks
Wednesday 21 October 2015 17:00 - 19:00
Lecturer: Bert Clever (Hansa Hydrocarbons Ltd.)
17:00 - 18:00 Social Hour
18:00 - 19:00 Lecture
Rotliegend exploration on the NE Dutch offshore proved rather unsuccessful in the last 5 decades although the play was already confirmed in 1977 just across the border in the southern German North Sea (SGNS). However, despite this confirmation, no development has yet occured. Main culprits are unclear reservoir distribution and poor seismic imaging (frequently vintage 2D only). To compound this, data access in Germany is restrictive and a unified cross-border thinking has been slow to mature.
Hansa’s focus is on the offshore area on either side of the Dutch-German offshore Median Line, particularly on Rotliegend reservoir distribution. Regionally, the classical Slochteren Fm extends from the Groningen area into onshore Germany where its equivalent (Hannover/Dethlingen Fm’s) shows a similar rapid shale-out to the north.
However, German onshore wells show older Rotliegend sands (Havel subgroup and lower part of Dethlingen Fm) to be preserved in N-S oriented, synsedimentary grabens and extend far into the offshore; much further than the Slochteren shale out. Similarly we have recognised the lower part of the Dethlingen Fm (Findorf Mbr) in the southern part of the study area. Previously, the offshore sands at the base of the Rotliegend were collectively lumped into one category, the Basal Rotliegend sands in Germany and the Lower Slochteren mbr in the Netherlands.
Towards the western part of the SGNS the graben system seems to lose its synsedimentary control on Rotliegend sands and WNW-ESE synsedimentary strike-slip faults appear to take over. These faults allowed, at least locally, for preservation of sands when base level rise resulted in a back-stepping pattern of the different, pre-Slochteren sands. Regionally, these sands pinch-out in a western direction, albeit in an irregular pattern. Hansa mapped these reservoirs in the NE part of the Dutch offshore and the adjacent SGNS, showing key control of accomodation space to sand preservation.
Key to successful exploration is the recognition of areas of sand preservation in combination with detailed mapping on structure and presence of undelying (mature) Westphalian; hence 3D is mandatory. The Basal Rotliegend sandstones are generally low acoustic impedance relative to the sediments above and below and can therefore be mapped effectively using coloured inversion volumes, with acoustic properties dependent predominantly on porosity.
Consequently coloured inversion has been used to assist in mapping sand presence and accomodation space. Hansa has implemented this process in the 4Quads area (G18,H16,M3,N1; successfully farmed out to Engie) with its 3D acquired in 2014 and the award of the GEms acreage (N4,N5,N7c,N8) in 2015. Current work is to mature the substantial reward exceeding 2 Tscf and 1 Tscf of GIIP respectively in the two licence areas. A number of structures have been drilled previously and tested gas by sub-optimally placed wells; hence the risks involved with our future drilling plans are modest.
lecture · drinks
Wednesday 18 November 2015 17:00 - 19:00
17:00 - 18:00 - Social hour
18:00 - 19:00 - Lecture
lecture · dinner · drinks
Wednesday 16 December 2015