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Publication . Article . Other literature type . 2021

Wireline distributed acoustic sensing allows 4.2 km deep vertical seismic profiling of the Rotliegend 150 °C geothermal reservoir in the North German Basin

Jan Henninges; Evgeniia Martuganova; Manfred Stiller; Ben Norden; Charlotte M. Krawczyk;
Open Access
Published: 25 Feb 2021
Country: Germany
Abstract
We performed so-far-unprecedented deep wireline vertical seismic profiling at the Groß Schönebeck site with the novel method of distributed acoustic sensing (DAS) to gain more detailed information on the structural setting and geometry of the geothermal reservoir, which is comprised of volcanic rocks and sediments of Lower Permian age. During the survey of 4 d only, we acquired data for 61 source positions using hybrid wireline fiber-optic sensor cables deployed in two 4.3 km deep, already existing wells. While most of the recorded data have a very good signal-to-noise ratio, individual sections of the profiles are affected by characteristic coherent noise patterns. This ringing noise results from incomplete coupling of the sensor cable to the borehole wall, and it can be suppressed to a large extent using suitable filtering methods. After conversion to strain rate, the DAS data exhibit a high similarity to the vertical component data of a conventional borehole geophone. We derived accurate time–depth relationships, interval velocities, and corridor stacks from the recorded data. Based on integration with other well data and geological information, we show that the top of a porous and permeable sandstone interval of the geothermal reservoir can be identified by a positive reflection event. Overall, the sequence of reflection events shows a different character for both wells explained by lateral changes in lithology. The top of the volcanic rocks has a somewhat different seismic response in both wells, and no clear reflection event is obvious at the postulated base of the volcanic rocks, so that their thickness cannot be inferred from individual reflection events in the seismic data alone. The DAS method enabled measurements at elevated temperatures up to 150 ∘C over extended periods and led to significant time and cost savings compared to deployment of a conventional borehole geophone string. This wireline approach finally suggests significant implications for observation options in old wells for a variety of purposes.
Subjects by Vocabulary

Dewey Decimal Classification: ddc:550

Library of Congress Subject Headings: lcsh:Geology lcsh:QE1-996.5 lcsh:Stratigraphy lcsh:QE640-699

Microsoft Academic Graph classification: Reflection (physics) Lithology Petrology Distributed acoustic sensing Borehole Vertical seismic profile Volcanic rock geography.geographical_feature_category geography Geophone Wireline Geology

Subjects

Paleontology, Stratigraphy, Earth-Surface Processes, Geochemistry and Petrology, Geology, Geophysics, Soil Science

42 references, page 1 of 5

Barberan, C., Allanic, C., Avila, D., Hy-Billiot, J., Hartog, A., Frignet, B., and Lees, G.: Multi-offset seismic acquisition using optical fiber behind tubing, in: Conference Proceedings, 74th EAGE Conference and Exhibition, Copenhagen, Denmark, 4-7 June, Y003, 2012.

Bauer, K., Moeck, I., Norden, B., Schulze, A., Weber, M., and Wirth, H.: Tomographic P wave velocity and vertical velocity gradient structure across the geothermal site Groß Schönebeck (NE German Basin): Relationship to lithology, salt tectonics, and thermal regime, J. Geophys. Res., 115, B08312, https://doi.org/10.1029/2009jb006895, 2010. [OpenAIRE]

Bauer, K., Norden, B., Ivanova, A., Stiller, M., and Krawczyk, C. M.: Wavelet transform-based seismic facies classification and modelling: application to a geothermal target horizon in the NE German Basin, Geophys. Prospect., 68, 466-482, https://doi.org/10.1111/1365-2478.12853, 2019. [OpenAIRE]

Blöcher, G., Cacace, M., Reinsch, T., and Watanabe, N.: Evaluation of three exploitation concepts for a deep geothermal system in the North German Basin, Comput. Geosci., 82, 120-129, https://doi.org/10.1016/j.cageo.2015.06.005, 2015.

Cai, Z., Wang, Y., Liu, C., Zhang, Q., and Xu, X.: Cable noise analysis and suppression in DAS-VSP data, AAPG/SEG International Conference and Exhibition, Barcelona, Spain, 3-6 April 2016, 170, 2016.

Chen, J., Ning, J., Chen, W., Wang, X., Wang, W., and Zhang, G.: Distributed acoustic sensing coupling noise removal based on sparse optimization, Interpretation, 7, 373-382, https://doi.org/10.1190/int-2018-0080.1, 2019.

Constantinou, A., Farahani, A., Cuny, T., and Hartog, A.: Improving DAS acquisition by real-time monitoring of wireline cable coupling, in: SEG Technical Program Expanded Abstracts, 5603- 5607, 2016. [OpenAIRE]

Correa, J., Egorov, A., Tertyshnikov, K., Bona, A., Pevzner, R., Dean, T., Freifeld, B., and Marshall, S.: Analysis of signal to noise and directivity characteristics of das VSP at near and far offsets-A CO2CRC Otway Project data example, Leading Edge, 36, 991-997, https://doi.org/10.1190/tle36120994a1.1, 2017.

Daley, T. M., Freifeld, B. M., Ajo-Franklin, J., Dou, S., Pevzner, R., Shulakova, V., Kashikar, S., Miller, D. E., Goetz, J., Henninges, J., and Lueth, S.: Field testing of fiber-optic distributed acoustic sensing (DAS) for subsurface seismic monitoring, Leading Edge, 32, 699-706, https://doi.org/10.1190/tle32060699.1, 2013.

Daley, T. M., Miller, D. E., Dodds, K., Cook, P., and Freifeld, B. M.: Field testing of modular borehole monitoring with simultaneous distributed acoustic sensing and geophone vertical seismic profiles at Citronelle, Alabama, Geophys. Prospect., 64, 1318-1334, https://doi.org/10.1111/1365-2478.12324, 2016.

Funded by
EC| EPOS IP
Project
EPOS IP
EPOS Implementation Phase
  • Funder: European Commission (EC)
  • Project Code: 676564
  • Funding stream: H2020 | RIA
,
EC| DESTRESS
Project
DESTRESS
Demonstration of soft stimulation treatments of geothermal reservoirs
  • Funder: European Commission (EC)
  • Project Code: 691728
  • Funding stream: H2020 | IA
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