%0 Journal Article %1 Zimmermann2009 %A Zimmermann, Günter %A Tischner, Torsten %A Legarth, Björn %A Huenges, Ernst %D 2009 %J Pure and Applied Geophysics %K 2009 EGS Groß-Schönebeck %N 5 %P 1089--1106 %T Pressure-dependent Production Efficiency of an Enhanced Geothermal System (EGS): Stimulation Results and Implications for Hydraulic Fracture Treatments %U http://dx.doi.org/10.1007/s00024-009-0482-5 %V 166 %X A series of stimulation experiments were carried out at the geothermal research well in Groß Schönebeck (EGrSk 3/90) locatedin the northeastern part of Germany. The intended purpose of these experiments was to develop concepts for a productivityincrease of the geothermal well to create an Enhanced Geothermal System (EGS). Two different kinds of stimulation types wereperformed. Hydraulic gel-proppant stimulations were conducted in sandstone sections with high initial permeability. Then adifferent fracturing concept was applied injecting high amounts of water. This waterfrac stimulation was realized in the entireopen section including sandstones and volcanic rocks. Evidence of the creation and properties of a very long vertical fracturewas retrieved from pressure response analyses demonstrating a bilinear flow regime. The production efficiency of the producedartificial fractures shows a strong dependence on reservoir pressure. At increased reservoir pressure the artificial fracturesof all stimulated intervals are highly conductive and subsequently become less conductive during pressure decline. Hence therange of a suitable reservoir pressure is constrained by this fracture efficiency and limits the usage of this well as aninjection well for geothermal power production.

@article{Zimmermann2009, abstract = {A series of stimulation experiments were carried out at the geothermal research well in Groß Schönebeck (EGrSk 3/90) locatedin the northeastern part of Germany. The intended purpose of these experiments was to develop concepts for a productivityincrease of the geothermal well to create an Enhanced Geothermal System (EGS). Two different kinds of stimulation types wereperformed. Hydraulic gel-proppant stimulations were conducted in sandstone sections with high initial permeability. Then adifferent fracturing concept was applied injecting high amounts of water. This waterfrac stimulation was realized in the entireopen section including sandstones and volcanic rocks. Evidence of the creation and properties of a very long vertical fracturewas retrieved from pressure response analyses demonstrating a bilinear flow regime. The production efficiency of the producedartificial fractures shows a strong dependence on reservoir pressure. At increased reservoir pressure the artificial fracturesof all stimulated intervals are highly conductive and subsequently become less conductive during pressure decline. Hence therange of a suitable reservoir pressure is constrained by this fracture efficiency and limits the usage of this well as aninjection well for geothermal power production.}, added-at = {2011-01-19T18:08:04.000+0100}, author = {Zimmermann, Günter and Tischner, Torsten and Legarth, Björn and Huenges, Ernst}, biburl = {https://www.bibsonomy.org/bibtex/2bebdae5a6e9c246fff6367afe4e8c970/thorade}, description = {SpringerLink - Zeitschriftenbeitrag}, interhash = {57b810bb44919bd569be34da7a7269c2}, intrahash = {bebdae5a6e9c246fff6367afe4e8c970}, journal = {Pure and Applied Geophysics}, keywords = {2009 EGS Groß-Schönebeck}, month = {07}, number = 5, pages = {1089--1106}, timestamp = {2011-01-19T18:08:04.000+0100}, title = {Pressure-dependent Production Efficiency of an Enhanced Geothermal System (EGS): Stimulation Results and Implications for Hydraulic Fracture Treatments}, url = {http://dx.doi.org/10.1007/s00024-009-0482-5}, volume = 166, year = 2009 }