Page 154 - Geothermal Energy Systems Exploration, Development, and Utilization

130 3 Drilling into Geothermal Reservoirs

Geological profile
Quaternary
Well sections
Tertinary Sand
Clay
Cretaceous unconsol, sandstone Roller cone bit
limestone
Anchor casing
Jurassic (Liassic)
unconsol, sandstone Casing shoe
Marl Setting depth
ctlaystone
Upper triassic
unconsol, sandstone TCI bits
Marl PDC bit
Limestone Combined production casing
Middle triassic
Limestone
Anhydrite
Siltstone
Sandstone
Lower triassic
Siltstone
Sandstone Casing shoe
Setting depth
1. Phase of directional drilling
Upper permian
(Zechstein) Devation toward WNW

End of 1. Phase of directional drilling

Evaporties
TCI bits
Liner-Production casing

Liner shoe
Up. Rotliegend Setting depth 2. Phase of directional drilling
Siltstone TCI & PDC Deviation toward WNW
Lower permian Liner-Production casing
Sandstone End of 2. Phase
Liner shoe
Low. Rotliegend Volcanic rock Setting depth TCI bits
Perforated liner
End of well: 4500 m
Figure 3.11 General well completion scheme.
Example of the geothermal well GTGrSk4/05 (Groß
Sch¨onebeck/Germany).