uu.seUppsala University Publications
Change search
Link to record
Permanent link

Direct link
BETA
Sopher, Daniel
Publications (10 of 19) Show all publications
Sopher, D., Juhlin, C., Levendal, T., Erlstrom, M., Nilsson, K. & Da Silva Soares, J. P. (2019). Evaluation of the subsurface compressed air energy storage (CAES) potential on Gotland, Sweden. Environmental Earth Sciences, 78(6), Article ID 197.
Open this publication in new window or tab >>Evaluation of the subsurface compressed air energy storage (CAES) potential on Gotland, Sweden
Show others...
2019 (English)In: Environmental Earth Sciences, ISSN 1866-6280, E-ISSN 1866-6299, Vol. 78, no 6, article id 197Article in journal (Refereed) Published
Abstract [en]

Wind energy is an important field of development for the island of Gotland, Sweden, especially since the island has set targets to generate 100% of its energy from renewable sources by 2025. Due to the variability of wind conditions, energy storage will be an important technology to facilitate the continued development of wind energy on Gotland and ensure a stable and secure supply of electricity. In this study, the feasibility of utilizing the Middle Cambrian Faludden sandstone reservoir on Gotland for Compressed Air Energy Storage (CAES) is assessed. Firstly, a characterization of the sandstone beneath Gotland is presented, which includes detailed maps of reservoir thickness and top reservoir structure. Analysis of this information shows that the properties of the Faludden sandstone and associated cap rock appear favorable for the application of CAES. Seven structural closures are identified below the eastern and southern parts of Gotland, which could potentially be utilized for CAES. Scoping estimates of the energy storage capacity and flow rate for these closures within the Faludden sandstone show that industrial scale CAES could be possible on Gotland.

Place, publisher, year, edition, pages
SPRINGER, 2019
Keywords
Faludden reservoir, OPAB data set, Gas storage, Baltic Basin, Baltic Sea, Wind power
National Category
Other Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:uu:diva-380480 (URN)10.1007/s12665-019-8196-1 (DOI)000460829600006 ()
Funder
Swedish Research Council, 2010-3657
Available from: 2019-04-15 Created: 2019-04-15 Last updated: 2019-04-15Bibliographically approved
Levendal, T., Sopher, D., Juhlin, C. & Lehnert, O. (2019). Investigation of an Ordovician carbonate mound beneath Gotland, Sweden, using 3D seismic and well data. Journal of Applied Geophysics, 162, 22-34
Open this publication in new window or tab >>Investigation of an Ordovician carbonate mound beneath Gotland, Sweden, using 3D seismic and well data
2019 (English)In: Journal of Applied Geophysics, ISSN 0926-9851, E-ISSN 1879-1859, Vol. 162, p. 22-34Article in journal (Refereed) Published
Abstract [en]

The Swedish island of Gotland is located within the Baltic Basin. During the Late Ordovician the region around Gotland was part of a shallow epicratonic basin in the southern subtropics. In these warm-water environments algae flourished, diverse reefs developed close to the coastline and further outboard carbonate mounds developed. These mounds formed rigid high relief structures surrounded by fine-grained siliciclastics and marls and can be detected on seismic images as isolated concave upwards features. The sedimentary succession beneath Gotland was intensely investigated in the 1970s and 1980s for its hydrocarbon potential, and subsequently, oil was commercially produced from reservoirs within Ordovician mounds. In 1981, a 3D seismic survey was conducted by Horizon Exploration Ltd. over the Fardume mound on northern Gotland. To date no results from these 3D data have been published in scientific literature.

The region of Gotland aims to produce 100% of its energy from renewable sources and currently much of Gotland's electricity is provided by wind turbines. Due to the intermittent nature of wind power, one solution to regulate the supply of electricity from wind energy is Compressed Air Energy Storage (CAES).

In this study, we convert the 3D seismic survey acquired over the Fardume mound from scanned TIFF images to SEGY format. These data are then utilized together with well data to gain a better knowledge of the geological structure of the mound and to examine its reservoir characteristics and potential for CAES. To date, carbonate mounds on Gotland have mainly been reported in the scientific literature using well data. This 3D seismic survey, therefore, provides a rare opportunity to better characterize and investigate the structure of one of the carbonate mounds on Gotland.

Keywords
Sweden, Gotland, Carbonate mounds, Late Ordovician, OPAB dataset, Seismic interpretation, 3D seismic, CAES
National Category
Geophysics Geology
Identifiers
urn:nbn:se:uu:diva-383000 (URN)10.1016/j.jappgeo.2019.01.008 (DOI)000465056200003 ()
Funder
Swedish Research CouncilGerman Research Foundation (DFG), LE 867/8-1German Research Foundation (DFG), LE 867/8-2
Available from: 2019-05-21 Created: 2019-05-21 Last updated: 2019-10-12
Levendal, T. C., Lehnert, O., Sopher, D., Erlström, M. & Juhlin, C. (2019). Ordovician carbonate mud mounds of the Baltoscandian Basin in time and space - A geophysical approach. Palaeogeography, Palaeoclimatology, Palaeoecology, 535, Article ID 109345.
Open this publication in new window or tab >>Ordovician carbonate mud mounds of the Baltoscandian Basin in time and space - A geophysical approach
Show others...
2019 (English)In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 535, article id 109345Article in journal (Refereed) Published
Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Baltica, Carbonate mud mounds, Gotland, OPAB dataset, Seismic interpretation, Sweden
National Category
Earth and Related Environmental Sciences Geophysics
Identifiers
urn:nbn:se:uu:diva-393044 (URN)10.1016/j.palaeo.2019.109345 (DOI)
Available from: 2019-09-17 Created: 2019-09-17 Last updated: 2019-09-27
Sopher, D. (2018). Converting scanned images of seismic reflection data into SEG-Y format. EARTH SCIENCE INFORMATICS, 11(2), 241-255
Open this publication in new window or tab >>Converting scanned images of seismic reflection data into SEG-Y format
2018 (English)In: EARTH SCIENCE INFORMATICS, ISSN 1865-0473, Vol. 11, no 2, p. 241-255Article in journal (Refereed) Published
Abstract [en]

Archives across the world contain vast amounts of old or "vintage" seismic reflection data, which are largely inaccessible for geo-scientific research, due to the out-dated media on which they are stored. Despite the age of these data, they often have great potential to be of use in modern day research. It is often the case that seismic reflection data within these archives are only available as a processed stacked section, printed on paper or film. In this study, a method for the conversion (vectorization) of scanned images of stacked reflection seismic data to standard SEG-Y format is presented. The method addresses data displayed with a line denoting the waveform, where areas on one side of the baseline are shaded (i.e. wiggle trace, variable fill). The method provides an improvement on other published methods utilized within currently available academic software. Unlike previous studies, the method used to detect trace baselines and to detect and remove timelines on the seismic image is described in detail. Furthermore, a quantitative analysis of the performance of the method is presented, showing that an average trace-to-trace correlation coefficient of between 0.8 and 0.95 can be achieved for typical plotting styles. Finally, a case study where the method is applied to vectorize over 1700 km of land seismic data from the island of Gotland (Sweden) is presented.

Keywords
Vectorization / vectorisation, Digitization / digitisation, Vintage / historical data, Analogue to digital, OPAB dataset, TIFF to SEGY
National Category
Geophysics
Identifiers
urn:nbn:se:uu:diva-356859 (URN)10.1007/s12145-017-0329-z (DOI)000431896100007 ()
Funder
Swedish Research Council, 2010-3657
Available from: 2018-08-15 Created: 2018-08-15 Last updated: 2018-08-15Bibliographically approved
Muhamad, H., Juhlin, C., Malehmir, A. & Sopher, D. (2018). Integrated interpretation of geophysical data of the Paleozoic structure in the northwestern part of the Siljan Ring impact crater, central Sweden. Journal of Applied Geophysics, 148, 201-215
Open this publication in new window or tab >>Integrated interpretation of geophysical data of the Paleozoic structure in the northwestern part of the Siljan Ring impact crater, central Sweden
2018 (English)In: Journal of Applied Geophysics, ISSN 0926-9851, E-ISSN 1879-1859, Vol. 148, p. 201-215Article in journal (Refereed) Published
Abstract [en]

The Siljan Ring impact structure is the largest known impact structure in Europe and is Late Devonian in age. It contains a central uplift that is about 20-30 km in diameter and is surrounded by a ring-shaped depression. The Siljan area is one of the few areas in Sweden where the Paleozoic sequence has not been completely eroded, making it an important location for investigation of the geological and tectonic history of Baltica during the Paleozoic. The Paleozoic strata in this area also provide insight into the complex deformation processes associated with the impact. In this study we focus on the northwestern part of the Siljan Ring, close to the town of Orsa, with the main objective of characterizing the subsurface Paleozoic succession and uppermost Precambrian crystalline rocks along a series of seismic reflection profiles, some of which have not previously been published. We combine these seismic data with gravity and magnetic data and seismic traveltime tomography results to produce an integrated interpretation of the subsurface in the area. Our interpretation shows that the Paleozoic sequence in this area is of a relatively constant thickness, with a total thickness typically between 300 and 500 m. Faulting appears to be predominantly extensional, which we interpret to have occurred during the modification stage of the impact. Furthermore, based on the geophysical data in this area, we interpret that the impact related deformation to differ in magnitude and style from other parts of the Siljan Ring.

National Category
Geophysics
Identifiers
urn:nbn:se:uu:diva-311546 (URN)10.1016/j.jappgeo.2017.10.001 (DOI)000424171900019 ()
Available from: 2016-12-28 Created: 2016-12-28 Last updated: 2018-03-28Bibliographically approved
Xu, Z., Sopher, D., Juhlin, C., Han, L. & Gong, X. (2018). Radon-domain interferometric interpolation for reconstruction of the near-offset gap in marine seismic data. Journal of Applied Geophysics, 151, 125-141
Open this publication in new window or tab >>Radon-domain interferometric interpolation for reconstruction of the near-offset gap in marine seismic data
Show others...
2018 (English)In: Journal of Applied Geophysics, ISSN 0926-9851, E-ISSN 1879-1859, Vol. 151, p. 125-141Article in journal (Refereed) Published
Abstract [en]

In towed marine seismic data acquisition, a gap between the source and the nearest recording channel is typical. Therefore, extrapolation of the missing near-offset traces is often required to avoid unwanted effects in subsequent data processing steps. However, most existing interpolation methods perform poorly when extrapolating traces. Interferometric interpolation methods are one particular method that have been developed for filling in trace gaps in shot gathers. Interferometry-type interpolation methods differ from conventional interpolation methods as they utilize information from several adjacent shot records to fill in the missing traces. In this study, we aim to improve upon the results generated by conventional time-space domain interferometric interpolation by performing interferometric interpolation in the Radon domain, in order to overcome the effects of irregular data sampling and limited source-receiver aperture. We apply both time-space and Radon-domain interferometric interpolation methods to the Sigsbee2B synthetic dataset and a real towed marine dataset from the Baltic Sea with the primary aim to improve the image of the seabed through extrapolation into the near-offset gap. Radon-domain interferometric interpolation performs better at interpolating the missing near offset traces than conventional interferometric interpolation when applied to data with irregular geometry and limited source-receiver aperture. We also compare the interferometric interpolated results with those obtained using solely Radon transform (RT) based interpolation and show that interferometry-type interpolation performs better than solely RT-based interpolation when extrapolating the missing near-offset traces. After data processing, we show that the image of the seabed is improved by performing interferometry-type interpolation, especially when Radon-domain interferometric interpolation is applied.

Keywords
Interferometric interpolation, Cross-correlation, Multiple, Near-offset gap, Radon transform
National Category
Geophysics
Identifiers
urn:nbn:se:uu:diva-354247 (URN)10.1016/j.jappgeo.2018.02.012 (DOI)000430903200012 ()
Available from: 2018-06-29 Created: 2018-06-29 Last updated: 2018-06-29Bibliographically approved
Xu, Z., Sopher, D., Juhlin, C. & Han, L. (2018). Reconstruction of the near-offset gap in marine seismic data using seismic interferometric interpolation. Geophysical Prospecting, 66(S1), 1-26
Open this publication in new window or tab >>Reconstruction of the near-offset gap in marine seismic data using seismic interferometric interpolation
2018 (English)In: Geophysical Prospecting, ISSN 0016-8025, E-ISSN 1365-2478, Vol. 66, no S1, p. 1-26Article in journal (Refereed) Published
Abstract [en]

In conventional seismic exploration, especially in marine seismic exploration, shot gathers with missing near-offset traces are common. Interferometric interpolation methods are one of a range of different methods that have been developed to solve this problem. Interferometric interpolation methods differ from conventional interpolation methods as they utilise information from multiples in the interpolation process. In this study, we apply both conventional interferometric interpolation (shot domain) and multi-domain interferometric interpolation (shot and receiver domain) to a synthetic and a real-towed marine dataset from the Baltic Sea with the primary aim of improving the image of the seabed by extrapolation of a near-offset gap. We utilise a matching filter after interferometric interpolation to partially mitigate artefacts and coherent noise associated with the far-field approximation and a limited recording aperture size. The results show that an improved image of the seabed is obtained after performing interferometric interpolation. In most cases, the results from multi-domain interferometric interpolation are similar to those from conventional interferometric interpolation. However, when the source-receiver aperture is limited, the multi-domain method performs better. A quantitative analysis for assessing the performance of interferometric interpolation shows that multi-domain interferometric interpolation typically performs better than conventional interferometric interpolation. We also benchmark the interpolated results generated by interferometric interpolation against those obtained using sparse recovery interpolation.

Place, publisher, year, edition, pages
WILEY, 2018
Keywords
Interferometric interpolation, Cross-correlation, Multiple, Near-offset gap, Interferometry
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:uu:diva-354515 (URN)10.1111/1365-2478.12599 (DOI)000428406000001 ()
Available from: 2018-07-16 Created: 2018-07-16 Last updated: 2018-07-16Bibliographically approved
Huang, F., Bergmann, P., Juhlin, C., Ivandic, M., Lüth, S., Ivanova, A., . . . Zhang, F. (2018). The first post-injection seismic monitor survey at the Ketzin pilot CO2 storage site: results from time-lapse analysis. Geophysical Prospecting, 66(1), 62-84
Open this publication in new window or tab >>The first post-injection seismic monitor survey at the Ketzin pilot CO2 storage site: results from time-lapse analysis
Show others...
2018 (English)In: Geophysical Prospecting, ISSN 0016-8025, E-ISSN 1365-2478, Vol. 66, no 1, p. 62-84Article in journal (Refereed) Published
Abstract [en]

The injection of CO2 at the Ketzin pilot CO2 storage site started in June 2008 and ended in August 2013. During the 62 months of injection, a total amount of about 67 kt of CO2 was injected into a saline aquifer. A third repeat 3D seismic survey, serving as the first post-injection survey was acquired in 2015, aiming to investigate the recent movement of the injected CO2. Consistent with the previous two time-lapse surveys, a predominantly WNW migration of the gaseous CO2 plume in the up-dip direction within the reservoir is inferred in this first post-injection survey. No systematic anomalies are detected through the reservoir overburden. The extent of the CO2 plume west of the injection site is almost identical to that found in the 2012 second repeat survey (after injection of 61 kt), however there is a significant decrease in its size east of the injection site. Assessment of the CO2 plume distribution suggests that the decrease in the size of the anomaly may be due to multiple factors, such as limited vertical resolution, CO2 dissolution and CO2 diffusion, in addition to the effects of ambient noise. 4D seismic modelling based on dynamic flow simulations indicates that a dynamic balance between the newly injected CO2 after the second repeat survey and the CO2 being dissolved and diffused was reached by the time of the first post-injection survey. Considering the considerable uncertainties in CO2 mass estimation, both patchy and non-patchy saturation models for the Ketzin site were taken into consideration.

Keywords
Seismic processing, Monitoring, 3D time-lapse (4D), CO2 sequestration
National Category
Geophysics
Identifiers
urn:nbn:se:uu:diva-301005 (URN)10.1111/1365-2478.12497 (DOI)000418349700006 ()
Funder
Vattenfall ABSwedish Research Council, 2010-3657
Available from: 2016-08-17 Created: 2016-08-17 Last updated: 2018-01-17Bibliographically approved
Huang, F., Juhlin, C., Han, L., Sopher, D., Ivandic, M., Norden, B., . . . Lüth, S. (2017). Feasibility of utilizing wavelet phase to map the CO2 plume at the Ketzin pilot site, Germany. Geophysical Prospecting, 65(2), 523-543
Open this publication in new window or tab >>Feasibility of utilizing wavelet phase to map the CO2 plume at the Ketzin pilot site, Germany
Show others...
2017 (English)In: Geophysical Prospecting, ISSN 0016-8025, E-ISSN 1365-2478, Vol. 65, no 2, p. 523-543Article in journal (Refereed) Published
Abstract [en]

Spectral decomposition is a powerful tool that can provide geological details dependent upon discrete frequencies. Complex spectral decomposition using inversion strategies differs from conventional spectral decomposition methods in that it produces not only frequency information but also wavelet phase information. This method was applied to a time‐lapse three‐dimensional seismic dataset in order to test the feasibility of using wavelet phase changes to detect and map injected carbon dioxide within the reservoir at the Ketzin carbon dioxide storage site, Germany. Simplified zero‐offset forward modelling was used to help verify the effectiveness of this technique and to better understand the wavelet phase response from the highly heterogeneous storage reservoir and carbon dioxide plume. Ambient noise and signal‐to‐noise ratios were calculated from the raw data to determine the extracted wavelet phase. Strong noise caused by rainfall and the assumed spatial distribution of sandstone channels in the reservoir could be correlated with phase anomalies. Qualitative and quantitative results indicate that the wavelet phase extracted by the complex spectral decomposition technique has great potential as a practical and feasible tool for carbon dioxide detection at the Ketzin pilot site.

Keywords
Time-lapse, Signal processing, Inversion, Modelling, Seismic.
National Category
Geophysics
Identifiers
urn:nbn:se:uu:diva-300994 (URN)10.1111/1365-2478.12383 (DOI)000398832100008 ()
Funder
Swedish Research Council, 2010-3657Vattenfall AB
Available from: 2016-08-17 Created: 2016-08-17 Last updated: 2018-09-18Bibliographically approved
Muhamad, H. A., Juhlin, C., Sopher, D., Lehnert, O., Arslan, A. & Meinhold, G. (2017). High-resolution seismic imaging of Paleozoic rocks in the Mora area, Siljan Ring structure, central Sweden. GFF, 139(4), 260-275
Open this publication in new window or tab >>High-resolution seismic imaging of Paleozoic rocks in the Mora area, Siljan Ring structure, central Sweden
Show others...
2017 (English)In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 139, no 4, p. 260-275Article in journal (Refereed) Published
Abstract [en]

The Late Devonian Siljan Ring structure in Sweden is the largest known impact structure in Europe. The present-day structure comprises a central dome that is about 20–30 km in diameter, which is surrounded by a ring-shaped depression. In this study, we focus on the southwestern part of the Siljan Ring with the aim to map the structure of the Paleozoic sedimentary rocks. Four 2D high-resolution seismic lines with a total length of about 3 km were acquired in the Mora area. A three component eighty-unit land streamer, combined with wireless recorders, was used for data acquisition along with a weight drop source. Processing of the data shows that clear reflections are present, but results are less distinct where external noise was present during acquisition or the maximum source-receiver offset was too short. Petrophysical measurements on core samples, core log data and a density model along one line were used to guide the interpretation of the seismic sections. These data demonstrate that fault blocks are present in the study area and that the individual blocks have been affected differently by impact-related tectonics.

National Category
Geophysics
Identifiers
urn:nbn:se:uu:diva-312020 (URN)10.1080/11035897.2017.1386712 (DOI)000416892400003 ()
Available from: 2017-01-04 Created: 2017-01-04 Last updated: 2018-03-07Bibliographically approved
Organisations

Search in DiVA

Show all publications