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Bagherbandi, Mohammad, ProfessorORCID iD iconorcid.org/0000-0003-0910-0596
Publications (10 of 47) Show all publications
Gido, N. A. A., Bagherbandi, M., Sjöberg, L. E. & Tenzer, R. (2019). Studying permafrost by integrating satellite and in situ data in the northern high-latitude regions. Acta Geophysica, 67(2), 721-734
Open this publication in new window or tab >>Studying permafrost by integrating satellite and in situ data in the northern high-latitude regions
2019 (English)In: Acta Geophysica, ISSN 1895-6572, E-ISSN 1895-7455, Vol. 67, no 2, p. 721-734Article in journal (Refereed) Published
Abstract [en]

There is an exceptional opportunity of achieving simultaneous and complementary data from a multitude of geoscience and environmental near-earth orbiting artificial satellites to study phenomena related to the climate change. These satellite missions provide the information about the various phenomena, such as sea level change, ice melting, soil moisture variation, temperature changes and earth surface deformations. In this study, we focus on permafrost thawing and its associated gravity change (in terms of the groundwater storage), and organic material changes using the gravity recovery and climate experiment (GRACE) data and other satellite- and ground-based observations. The estimation of permafrost changes requires combining information from various sources, particularly using the gravity field change, surface temperature change, and glacial isostatic adjustment. The most significant factor for a careful monitoring of the permafrost thawing is the fact that this process could be responsible for releasing an additional enormous amount of greenhouse gases emitted to the atmosphere, most importantly to mention carbon dioxide (CO2) and methane that are currently stored in the frozen ground. The results of a preliminary numerical analysis reveal a possible existence of a high correlation between the secular trends of greenhouse gases (CO2), temperature and equivalent water thickness (in permafrost active layer) in the selected regions. Furthermore, according to our estimates based on processing the GRACE data, the groundwater storage attributed due to permafrost thawing increased at the annual rates of 3.4, 3.8, 4.4 and 4.0 cm, respectively, in Siberia, North Alaska and Canada (Yukon and Hudson Bay). Despite a rather preliminary character of our results, these findings indicate that the methodology developed and applied in this study should be further improved by incorporating the in situ permafrost measurements.

Place, publisher, year, edition, pages
Springer, 2019
Keywords
Climate change, Permafrost, Gravity, Grace, Greenhouse gas
National Category
Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:hig:diva-29393 (URN)10.1007/s11600-019-00276-4 (DOI)2-s2.0-85062782688 (Scopus ID)
Available from: 2019-03-18 Created: 2019-03-18 Last updated: 2019-08-15Bibliographically approved
Gido, N. A. A., Bagherbandi, M. & Sjöberg, L. E. (2018). A gravimetric method to determine Horizontal Stress field due to flow in mantle in Fennoscandia. Geosciences Journal
Open this publication in new window or tab >>A gravimetric method to determine Horizontal Stress field due to flow in mantle in Fennoscandia
2018 (English)In: Geosciences Journal, ISSN 1226-4806Article in journal (Refereed) Epub ahead of print
Abstract [en]

Mass changes and flow in the Earth's mantle causes the Earth's crust not only to movevertically, but also horizontally and to tilt, and produce a major stress in the lithosphere.Here we use a gravimetric approach to model sub-lithosphere horizontal stress in theEarth's mantle and its temporal changes caused by geodynamical movements likemantle convection in Fennoscandia. The flow in the mantle is inferred from tectonicsand convection currents carrying heat from the interior of the Earth to the crust. Theresult is useful in studying how changes of the stress influence the stability of crust.The outcome of this study is an alternative approach to studying the stress and itschange using forward modelling and the Earth's viscoelastic models. We show that thedetermined horizontal stress using a gravimetric method is consistent with tectonicsand seismic activities. In addition, the secular rate of change of the horizontal stress,which is within 95 kPa/year, is larger outside the uplift dome than inside.

Keywords
horizontal stress, mantle convection, mass change, stress field, tectonics
National Category
Geophysics
Identifiers
urn:nbn:se:hig:diva-27317 (URN)10.1007/s12303-018-0046-8 (DOI)2-s2.0-85054552297 (Scopus ID)
Available from: 2018-06-24 Created: 2018-06-24 Last updated: 2018-12-05Bibliographically approved
Baranov, A., Tenzer, R. & Bagherbandi, M. (2018). Combined Gravimetric–Seismic Crustal Model for Antarctica. Surveys in geophysics, 39(1), 23-56
Open this publication in new window or tab >>Combined Gravimetric–Seismic Crustal Model for Antarctica
2018 (English)In: Surveys in geophysics, ISSN 0169-3298, E-ISSN 1573-0956, Vol. 39, no 1, p. 23-56Article in journal (Refereed) Published
Abstract [en]

The latest seismic data and improved information about the subglacial bedrock relief are used in this study to estimate the sediment and crustal thickness under the Antarctic continent. Since large parts of Antarctica are not yet covered by seismic surveys, the gravity and crustal structure models are used to interpolate the Moho information where seismic data are missing. The gravity information is also extended offshore to detect the Moho under continental margins and neighboring oceanic crust. The processing strategy involves the solution to the Vening Meinesz-Moritz’s inverse problem of isostasy constrained on seismic data. A comparison of our new results with existing studies indicates a substantial improvement in the sediment and crustal models. The seismic data analysis shows significant sediment accumulations in Antarctica, with broad sedimentary basins. According to our result, the maximum sediment thickness in Antarctica is about 15 km under Filchner-Ronne Ice Shelf. The Moho relief closely resembles major geological and tectonic features. A rather thick continental crust of East Antarctic Craton is separated from a complex geological/tectonic structure of West Antarctica by the Transantarctic Mountains. The average Moho depth of 34.1 km under the Antarctic continent slightly differs from previous estimates. A maximum Moho deepening of 58.2 km under the Gamburtsev Subglacial Mountains in East Antarctica confirmed the presence of deep and compact orogenic roots. Another large Moho depth in East Antarctica is detected under Dronning Maud Land with two orogenic roots under Wohlthat Massif (48–50 km) and the Kottas Mountains (48–50 km) that are separated by a relatively thin crust along Jutulstraumen Rift. The Moho depth under central parts of the Transantarctic Mountains reaches 46 km. The maximum Moho deepening (34–38 km) in West Antarctica is under the Antarctic Peninsula. The Moho depth minima in East Antarctica are found under the Lambert Trench (24–28 km), while in West Antarctica the Moho depth minima are along the West Antarctic Rift System under the Bentley depression (20–22 km) and Ross Sea Ice Shelf (16–24 km). The gravimetric result confirmed a maximum extension of the Antarctic continental margins under the Ross Sea Embayment and the Weddell Sea Embayment with an extremely thin continental crust (10–20 km).

Place, publisher, year, edition, pages
Springer Netherlands, 2018
Keywords
Antarctica, Crust, Gravity, Ice, Isostasy, Moho, Sediments, Seismic data, Geodesy, Geology, Gravitation, Inverse problems, Landforms, Sea ice, Seismic response, Seismic waves, Structural geology, Seismic datas, Seismology
National Category
Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:hig:diva-25364 (URN)10.1007/s10712-017-9423-5 (DOI)000419172900002 ()2-s2.0-85029739928 (Scopus ID)
Note

Funding Agency: National Science Foundation of China (NSFC)

Grant Number: 41429401 

Funding Agency: Russian Foundation for Basic Research 

Grant Number: 16-55-12033  13-05-01123 

Available from: 2017-10-04 Created: 2017-10-04 Last updated: 2018-03-13Bibliographically approved
Baranov, A., Bagherbandi, M. & Tenzer, R. (2018). Combined Gravimetric-Seismic Moho Model of Tibet. Geosciences, 8(12), Article ID UNSP 461.
Open this publication in new window or tab >>Combined Gravimetric-Seismic Moho Model of Tibet
2018 (English)In: Geosciences, ISSN 2076-3263, Vol. 8, no 12, article id UNSP 461Article in journal (Refereed) Published
Abstract [en]

Substantial progress has been achieved over the last four decades to better understand a deep structure in the Himalayas and Tibet. Nevertheless, the remoteness of this part of the world still considerably limits the use of seismic data. A possible way to overcome this practical restriction partially is to use products from the Earth’s satellite observation systems. Global topographic data are provided by the Shuttle Radar Topography Mission (SRTM). Global gravitational models have been derived from observables delivered by the gravity-dedicated satellite missions, such as the Gravity Recovery and Climate Experiment (GRACE) and the Gravity field and steady-state Ocean Circulation Explorer (GOCE). Optimally, the topographic and gravity data should be combined with available results from tomographic surveys to interpret the lithospheric structure, including also a Moho relief. In this study, we use seismic, gravity, and topographic data to estimate the Moho depth under orogenic structures of the Himalayas and Tibet. The combined Moho model is computed based on solving the Vening Meinesz-Moritz (VMM) inverse problem of isostasy, while incorporating seismic data to constrain the gravimetric solution. The result of the combined gravimetric-seismic data analysis exhibits an anticipated more detailed structure of the Moho geometry when compared to the solution obtained merely from seismic data. This is especially evident over regions with sparse seismic data coverage. The newly-determined combined Moho model of Tibet shows a typical contrast between a thick crustal structure of orogenic formations compared to a thinner crust of continental basins. The Moho depth under most of the Himalayas and the Tibetan Plateau is typically within 60-70 km. The maximum Moho deepening of similar to 76 km occurs to the south of the Bangong-Nujiang suture under the Lhasa terrane. Local maxima of the Moho depth to similar to 74 km are also found beneath Taksha at the Karakoram fault. This Moho pattern generally agrees with the findings from existing gravimetric and seismic studies, but some inconsistencies are also identified and discussed in this study.

Place, publisher, year, edition, pages
MDPI, 2018
Keywords
Moho; satellite gravity missions; seismic data; terrain model; Tibet
National Category
Environmental Engineering
Identifiers
urn:nbn:se:hig:diva-29330 (URN)10.3390/geosciences8120461 (DOI)000455388200034 ()
Note

Funding agencies:

Hong Kong Research Grants Council  Grant no: 1-ZE8F 

Russian Foundation for Basic Research  Grant no: 16-55-12033 

Available from: 2019-02-27 Created: 2019-02-27 Last updated: 2019-02-27Bibliographically approved
Tenzer, R., Foroughi, I., Sjöberg, L. E., Bagherbandi, M., Hirt, C. & Pitoňák, M. (2018). Definition of Physical Height Systems for Telluric Planets and Moons. Surveys in geophysics, 39(3), 313-335
Open this publication in new window or tab >>Definition of Physical Height Systems for Telluric Planets and Moons
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2018 (English)In: Surveys in geophysics, ISSN 0169-3298, E-ISSN 1573-0956, Vol. 39, no 3, p. 313-335Article, review/survey (Refereed) Published
Abstract [en]

In planetary sciences, the geodetic (geometric) heights defined with respect to the reference surface (the sphere or the ellipsoid) or with respect to the center of the planet/moon are typically used for mapping topographic surface, compilation of global topographic models, detailed mapping of potential landing sites, and other space science and engineering purposes. Nevertheless, certain applications, such as studies of gravity-driven mass movements, require the physical heights to be defined with respect to the equipotential surface. Taking the analogy with terrestrial height systems, the realization of height systems for telluric planets and moons could be done by means of defining the orthometric and geoidal heights. In this case, however, the definition of the orthometric heights in principle differs. Whereas the terrestrial geoid is described as an equipotential surface that best approximates the mean sea level, such a definition for planets/moons is irrelevant in the absence of (liquid) global oceans. A more natural choice for planets and moons is to adopt the geoidal equipotential surface that closely approximates the geometric reference surface (the sphere or the ellipsoid). In this study, we address these aspects by proposing a more accurate approach for defining the orthometric heights for telluric planets and moons from available topographic and gravity models, while adopting the average crustal density in the absence of reliable crustal density models. In particular, we discuss a proper treatment of topographic masses in the context of gravimetric geoid determination. In numerical studies, we investigate differences between the geodetic and orthometric heights, represented by the geoidal heights, on Mercury, Venus, Mars, and Moon. Our results reveal that these differences are significant. The geoidal heights on Mercury vary from − 132 to 166 m. On Venus, the geoidal heights are between − 51 and 137 m with maxima on this planet at Atla Regio and Beta Regio. The largest geoid undulations between − 747 and 1685 m were found on Mars, with the extreme positive geoidal heights under Olympus Mons in Tharsis region. Large variations in the geoidal geometry are also confirmed on the Moon, with the geoidal heights ranging from − 298 to 461 m. For comparison, the terrestrial geoid undulations are mostly within ± 100 m. We also demonstrate that a commonly used method for computing the geoidal heights that disregards the differences between the gravity field outside and inside topographic masses yields relatively large errors. According to our estimates, these errors are − 0.3/+ 3.4 m for Mercury, 0.0/+ 13.3 m for Venus, − 1.4/+ 125.6 m for Mars, and − 5.6/+ 45.2 m for the Moon.

Place, publisher, year, edition, pages
Springer Netherlands, 2018
Keywords
Geoid, Gravity, Heights, Moon, Planets, Topography, Geodesy, Geometry, Gravitation, Interplanetary flight, Mapping, Mercury (metal), Sea level, Density models, Equipotential surfaces, Geoid undulation, Orthometric heights, Planetary science, Topographic models
National Category
Geotechnical Engineering
Identifiers
urn:nbn:se:hig:diva-26087 (URN)10.1007/s10712-017-9457-8 (DOI)000429112400001 ()2-s2.0-85040314721 (Scopus ID)
Available from: 2018-01-31 Created: 2018-01-31 Last updated: 2018-06-04Bibliographically approved
Tenzer, R., Chen, W., Baranov, A. & Bagherbandi, M. (2018). Gravity maps of Antarctic lithospheric structure from remote-sensing and seismic data. Pure and Applied Geophysics, 175(6), 2181-2203
Open this publication in new window or tab >>Gravity maps of Antarctic lithospheric structure from remote-sensing and seismic data
2018 (English)In: Pure and Applied Geophysics, ISSN 0033-4553, E-ISSN 1420-9136, Vol. 175, no 6, p. 2181-2203Article in journal (Refereed) Published
Abstract [en]

Remote-sensing data from altimetry and gravity satellite missions combined with seismic information have been used to investigate the Earth’s interior, particularly focusing on the lithospheric structure. In this study, we use the subglacial bedrock relief BEDMAP2, the global gravitational model GOCO05S, and the ETOPO1 topographic/bathymetric data, together with a newly developed (continental-scale) seismic crustal model for Antarctica to compile the free-air, Bouguer, and mantle gravity maps over this continent and surrounding oceanic areas. We then use these gravity maps to interpret the Antarctic crustal and uppermost mantle structure. We demonstrate that most of the gravity features seen in gravity maps could be explained by known lithospheric structures. The Bouguer gravity map reveals a contrast between the oceanic and continental crust which marks the extension of the Antarctic continental margins. The isostatic signature in this gravity map confirms deep and compact orogenic roots under the Gamburtsev Subglacial Mountains and more complex orogenic structures under Dronning Maud Land in East Antarctica. Whereas the Bouguer gravity map exhibits features which are closely spatially correlated with the crustal thickness, the mantle gravity map reveals mainly the gravitational signature of the uppermost mantle, which is superposed over a weaker (long-wavelength) signature of density heterogeneities distributed deeper in the mantle. In contrast to a relatively complex and segmented uppermost mantle structure of West Antarctica, the mantle gravity map confirmed a more uniform structure of the East Antarctic Craton. The most pronounced features in this gravity map are divergent tectonic margins along mid-oceanic ridges and continental rifts. Gravity lows at these locations indicate that a broad region of the West Antarctic Rift System continuously extends between the Atlantic–Indian and Pacific–Antarctic mid-oceanic ridges and it is possibly formed by two major fault segments. Gravity lows over the Transantarctic Mountains confirms their non-collisional origin. Additionally, more localized gravity lows closely coincide with known locations of hotspots and volcanic regions (Marie Byrd Land, Balleny Islands, Mt. Erebus). Gravity lows also suggest a possible hotspot under the South Orkney Islands. However, this finding has to be further verified.

Place, publisher, year, edition, pages
Springer, 2018
Keywords
Antarctica, crust, gravity, lithosphere, upper mantle
National Category
Geophysics
Identifiers
urn:nbn:se:hig:diva-27316 (URN)10.1007/s00024-018-1795-z (DOI)000435590500017 ()2-s2.0-85048805707 (Scopus ID)
Available from: 2018-06-24 Created: 2018-06-24 Last updated: 2018-08-15Bibliographically approved
Bagherbandi, M., Bai, Y., Sjöberg, L., Tenzer, R., Abrehdary, M., Miranda, S. & Sanchez, J. M. A. (2017). Effect of the lithospheric thermal state on the Moho interface: a case study in South America. Journal of South American Earth Sciences, 76, 198-207
Open this publication in new window or tab >>Effect of the lithospheric thermal state on the Moho interface: a case study in South America
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2017 (English)In: Journal of South American Earth Sciences, ISSN 0895-9811, E-ISSN 1873-0647, Vol. 76, p. 198-207Article in journal (Refereed) Published
Abstract [en]

Gravimetric methods applied for Moho recovery in areas with sparse and irregular distribution of seismic data often assume only a constant crustal density. Results of latest studies, however, indicate that corrections for crustal density heterogeneities could improve the gravimetric result, especially in regions with a complex geologic/tectonic structure. Moreover, the isostatic mass balance reflects also the density structure within the lithosphere. The gravimetric methods should therefore incorporate an additional correction for the lithospheric mantle as well as deeper mantle density heterogeneities. Following this principle, we solve the Vening Meinesz-Moritz (VMM) inverse problem of isostasy constrained by seismic data to determine the Moho depth of the South American tectonic plate including surrounding oceans, while taking into consideration the crustal and mantle density heterogeneities. Our numerical result confirms that contribution of sediments significantly modifies the estimation of the Moho geometry especially along the continental margins with large sediment deposits. To account for the mantle density heterogeneities we develop and apply a method in order to correct the Moho geometry for the contribution of the lithospheric thermal state (i.e., the lithospheric thermal-pressure correction). In addition, the misfit between the isostatic and seismic Moho models, attributed mainly to deep mantle density heterogeneities and other geophysical phenomena, is corrected for by applying the non-isostatic correction. The results reveal that the application of the lithospheric thermal-pressure correction improves the RMS fit of the VMM gravimetric Moho solution to the CRUST1.0 (improves ∼ 1.9 km) and GEMMA (∼1.1 km) models and the point-wise seismic data (∼0.7 km) in South America.

Keywords
Crust, Gravity, Lithosphere, Moho, Thermal state
National Category
Geophysics Geosciences, Multidisciplinary Other Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:hig:diva-23685 (URN)10.1016/j.jsames.2017.02.010 (DOI)000402342800014 ()2-s2.0-85015736007 (Scopus ID)
Funder
Swedish National Space Board, 116/12
Note

Funding agencies:

NNSF of China  Grant no: 41506055 

Research Board at University of Gavle  Grant no: HIG-STYR 2015/32 

Available from: 2017-02-26 Created: 2017-02-26 Last updated: 2018-03-13Bibliographically approved
Tenzer, R., Bagherbandi, M., Chen, W. & Sjöberg, L. E. (2017). Global Isostatic Gravity Maps From Satellite Missions and Their Applications in the Lithospheric Structure Studies. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 10(2), 549-561
Open this publication in new window or tab >>Global Isostatic Gravity Maps From Satellite Missions and Their Applications in the Lithospheric Structure Studies
2017 (English)In: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, ISSN 1939-1404, E-ISSN 2151-1535, Vol. 10, no 2, p. 549-561Article in journal (Refereed) Published
Abstract [en]

Recent satellite gravity missions provide information on the Earth’s gravity field with a global and homogenous coverage. These data have been utilized in geoscience studies to investigate the Earth’s inner structure. In this study, we use the global gravitational models to compute and compare various isostatic gravity data. In particular, we compile global maps of the isostatic gravity disturbances by applying the Airy-Heiskanen and Pratt-Hayford isostatic theories based on assuming a local compensation mechanism. We further apply the Vening Meinesz-Moritz isostatic (flexural) model based on a more realistic assumption of the regional compensation mechanism described for the Earth’s homogenous and variable crustal structure. The resulting isostatic gravity fields are used to analyze their spatial and spectral characteristics with respect to the global crustal geometry. Results reveal that each of the applied compensation model yields a distinctive spatial pattern of the isostatic gravity field with its own spectral characteristics. The Airy-Heiskanen isostatic gravity disturbances provide a very smooth gravity field with no correlation with the crustal geometry. The Pratt-Hayford isostatic gravity disturbances are spatially highly correlated with the topography on land, while the Vening-Meinesz Moritz isostatic gravity disturbances are correlated with the Moho geometry. The complete crust-stripped isostatic gravity disturbances reveal a gravitational signature of the mantle lithosphere. These general characteristics provide valuable information for selection of a particular isostatic scheme, which could be used for gravimetric interpretations, depending on a purpose of the study.

Keywords
Earth; gravity; isostasy; satellite observation systems; topography
National Category
Geophysics
Identifiers
urn:nbn:se:hig:diva-24328 (URN)10.1109/JSTARS.2016.2556219 (DOI)000395466700015 ()2-s2.0-84966605787 (Scopus ID)
Note

Funding agencies:

National Science Foundation of China (NSFC)  grant no: 41429401 

Czech Ministry of Education, Youth and Sport by the National Program of Sustainability Grant no: LO1506 

Available from: 2017-06-16 Created: 2017-06-16 Last updated: 2018-03-13Bibliographically approved
Sjöberg, L. E. & Bagherbandi, M. (2017). Gravity Inversion and Integration: Theory and Applications in Geodesy and Geophysics. Cham: Springer Publishing Company
Open this publication in new window or tab >>Gravity Inversion and Integration: Theory and Applications in Geodesy and Geophysics
2017 (English)Book (Other academic)
Abstract [en]

This book contains theory and applications of gravity both for physical geodesy and geophysics. It identifies classical and modern topics for studying the Earth. Worked-out examples illustrate basic but important concepts of the Earth’s gravity field. In addition, coverage details the Geodetic Reference System 1980, a versatile tool in most applications of gravity data.

The authors first introduce the necessary mathematics. They then review classic physical geodesy, including its integral formulas, height systems and their determinations. The next chapter presents modern physical geodesy starting with the original concepts of M.S. Molodensky. A major part of this chapter is a variety of modifying Stokes’ formula for geoid computation by combining terrestrial gravity data and an Earth Gravitational Model.

Coverage continues with a discussion that compares today’s methods for modifying Stokes’ formulas for geoid and quasigeoid determination, a description of several modern tools in physical geodesy, and a review of methods for gravity inversion as well as analyses for temporal changes of the gravity field.

This book aims to broaden the view of scientists and students in geodesy and geophysics. With a focus on theory, it provides basic and some in-depth knowledge about the field from a geodesist’s perspective.

Place, publisher, year, edition, pages
Cham: Springer Publishing Company, 2017. p. xiv, 383
Keywords
Geoid determination textbook, Gravity inversion and temporal variation of gravity field, Physical geodesy and geophysics, Geodynamics and earth mass distribution, Moho and earth interior, 3D layered structure of the earth
National Category
Geophysics
Identifiers
urn:nbn:se:hig:diva-23686 (URN)10.1007/978-3-319-50298-4 (DOI)2-s2.0-85032838381 (Scopus ID)978-3-319-50297-7 (ISBN)978-3-319-50298-4 (ISBN)
Note

- Details theory and applications of gravity both for physical geodesy and geophysics

- Includes worked examples throughout the book

- Identifies classical and modern topics for studying the Earth

Available from: 2017-02-26 Created: 2017-02-26 Last updated: 2018-03-13Bibliographically approved
Nilfouroushan, F., Bagherbandi, M. & Gido, N. (2017). Ground Subsidence And Groundwater Depletion In Iran: Integrated approach Using InSAR and Satellite Gravimetry. In: : . Paper presented at Fringe 2017, the 10th International Workshop on “Advances in the Science and Applications of SAR Interferometry and Sentinel-1 InSAR”, 5-9 June 2017, Helsinki, Finland.
Open this publication in new window or tab >>Ground Subsidence And Groundwater Depletion In Iran: Integrated approach Using InSAR and Satellite Gravimetry
2017 (English)Conference paper, Poster (with or without abstract) (Other academic)
Abstract [en]

Long-term monitoring of temporal gravity field and ground water level changes in Iran and its associated ground subsidence seen by geodetic methods are important for water source and hazard management.The high-rate (cm to dm/year) ground subsidence in Iran has been widely investigated by using different geodetic techniques such as precise leveling, GPS and interferometric synthetic aperture radar (InSAR). The previous individual SAR sensors (e.g. ERS, ENVISAT and ALOS) or multi-sensors approach have successfully shown localized subsidence in different parts of Iran. Now, thanks to freely available new SAR sensor Sentinel-1A data, we aim at investigate further the subsidence problem in this region.

In this ongoing research, firstly, we use a series of Sentinel-1A SAR Images, acquired between 2014 to 2017 to generate subsidence-rate maps in different parts of the country. Then, we correlate the InSAR results with the monthly observations of the Gravity Recovery and Climate Experiment (GRACE) satellite mission in this region. The monthly GRACE data computed at CNES from 2002 to 2017 are used to compute the time series for total water storage changes. The Global Land Data Assimilation System( GLDAS) hydrological model (i.e. soil moisture, snow water equivalent and surface water) is used to estimate Groundwater changes from total water storage changes obtiaend from GRACE data.

So far, we have generated a few interferograms, using Sentinel-1A data and SNAP software, which shows a few cm subsidence in western Tehran in last 2 years. We will try more Sentinel images for this area to better constrain the rate and extent of deformation and will continue InSAR processing for the rest of the country to localize the deformation zones and their rates. We will finally comapre the rates of subsidence obtained from InSAR and the rate of groundwater changes estimated from GRACE data.

Keywords
InSAR, subsidence, GRACE, deformation, Water
National Category
Geosciences, Multidisciplinary
Identifiers
urn:nbn:se:hig:diva-23352 (URN)
Conference
Fringe 2017, the 10th International Workshop on “Advances in the Science and Applications of SAR Interferometry and Sentinel-1 InSAR”, 5-9 June 2017, Helsinki, Finland
Available from: 2017-01-21 Created: 2017-01-21 Last updated: 2018-03-13Bibliographically approved
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Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-0910-0596

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