Ein integrativer geodätisch-gravimetrischer Ansatz zur Erkundung von Subrosion im Erdfallgebiet Hamburg-Flottbek - Oberflächendeformation und Massentransfer

authored by: Adelheid Weise, Tobias Kersten, Ludger Timmen, Gerald Gabriel, Steffen Schön, Detlef Vogel
Abstract: Sinkholes occur due to leaching of soluble rocks generating subsidence at the surface. Their hazard potential is large, especially in urban areas. In the joint research project SIMULTAN (Sinkhole Instability: integrated MULTi-scale monitoring and ANalysis) the investigation and surveillance of sinkhole areas by methods of geophysics, petrophysics, applied geodesy, and hydrology aims at contributing to an early recognition system of instability, and in combination with modeling, at improving the understanding of subrosion processes. We focus on a region in the city of Hamburg where the subsidence areas Wobbe- See and Flottbek-Markt are located. Subsidence rates of about 1 mm/a are presumed to be caused by dissolution related to Othmarschen-Langenfelde Diapir. Following an integrative geodetic-gravimetric approach, surface deformation and mass transfer due to subrosion are observed since 01/2016 by repeated levelling and gravimetry campaigns. By tying the relative methods to a superior reference system, large-scale stability control is enabled. A local, relative GNSS network is linked via SAPOS to superior reference systems (ETRS89 and DHHN2016). Concerning gravity, annual absolute measurements are realized. First results regarding deformation indicate a long-term trend to subsidence in Wobbe-See and at Flottbek- Markt. Can we detect potential mass changes in urban areas? This is investigated by high-precision gravity measurement: Reproducible and significant temporal variations of gravity differences (std. dev. ±10 nm/s²) are comprising hydrological induced seasonal variations of several tens of nm/s², due to local conditions. The correlation with local hydrology is obvious. The intended correction of these hydrological effects will allow to separate possibly hidden effects of mass redistribution caused by dissolution and sinkhole development.
Organisation(s): Institute of Geodesy
Leibniz Research Centre FZ:GEO
External Organisation(s): Leibniz Institute for Applied Geophysics (LIAG)
Type: Article
Journal: AVN Allgemeine Vermessungs-Nachrichten
Volume: 125
Pages: 244-254
No. of pages: 11
ISSN: 0002-5968
Publication date: 01.01.2018
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Geography, Planning and Development, Civil and Structural Engineering, Earth and Planetary Sciences (miscellaneous)
Electronic version(s): https://gispoint.de/index.php?eID=dumpFile&t=f&f=13511&token=786afea29ccccd2891d0721245e9c37707170614&download= (Access: Open)
: Details in the research portal "Research@Leibniz University"

BibTeX

@article{8738b665b38c49f99e6d744277e9d9e5,
title = "Ein integrativer geod{\"a}tisch-gravimetrischer Ansatz zur Erkundung von Subrosion im Erdfallgebiet Hamburg-Flottbek - Oberfl{\"a}chendeformation und Massentransfer",
abstract = "Sinkholes occur due to leaching of soluble rocks generating subsidence at the surface. Their hazard potential is large, especially in urban areas. In the joint research project SIMULTAN (Sinkhole Instability: integrated MULTi-scale monitoring and ANalysis) the investigation and surveillance of sinkhole areas by methods of geophysics, petrophysics, applied geodesy, and hydrology aims at contributing to an early recognition system of instability, and in combination with modeling, at improving the understanding of subrosion processes. We focus on a region in the city of Hamburg where the subsidence areas Wobbe- See and Flottbek-Markt are located. Subsidence rates of about 1 mm/a are presumed to be caused by dissolution related to Othmarschen-Langenfelde Diapir. Following an integrative geodetic-gravimetric approach, surface deformation and mass transfer due to subrosion are observed since 01/2016 by repeated levelling and gravimetry campaigns. By tying the relative methods to a superior reference system, large-scale stability control is enabled. A local, relative GNSS network is linked via SAPOS to superior reference systems (ETRS89 and DHHN2016). Concerning gravity, annual absolute measurements are realized. First results regarding deformation indicate a long-term trend to subsidence in Wobbe-See and at Flottbek- Markt. Can we detect potential mass changes in urban areas? This is investigated by high-precision gravity measurement: Reproducible and significant temporal variations of gravity differences (std. dev. ±10 nm/s2) are comprising hydrological induced seasonal variations of several tens of nm/s2, due to local conditions. The correlation with local hydrology is obvious. The intended correction of these hydrological effects will allow to separate possibly hidden effects of mass redistribution caused by dissolution and sinkhole development.",
keywords = "Geo-monitoring measurements, Geophysics, GNSS, Gravimetry, Mass redistribution, Sinkhole, Temporal changes",
author = "Adelheid Weise and Tobias Kersten and Ludger Timmen and Gerald Gabriel and Steffen Sch{\"o}n and Detlef Vogel",
note = "DANK: Das Projekt SIMULTAN wird vom Bundesministerium f{\"u}r Bildung und Forschung (BMBF) im Sonderprogramm Geotechnologien (F{\"o}rderkennzeichen 03G0843A) gef{\"o}rdert. Wir danken allen beteiligten technischen Mitarbeitern des LIAG (Nivellement und Gravimetrie) sowie Studierenden der Leibniz-Universit{\"a}t (IfE) f{\"u}r die Unterst{\"u}tzung w{\"a}hrend der f{\"u}nf GNSS-Messkampagnen. Weiterhin sei an dieser Stelle ein besonderer Dank an die Abteilung MEA2 des Deutschen Elektronen-Synchrotrons (DESY) unter Leitung von Dr.- Ing. Johannes Prenting und der Landesvermessung Niedersachsen sowie Hamburg f{\"u}r die gute Kooperation ausgesprochen. Die Autoren bedanken sich ebenfalls beim CODE-Analysezentrum f{\"u}r die Verf{\"u}gbarkeit pr{\"a}ziser GNSS-Produkte.",
year = "2018",
month = jan,
day = "1",
language = "Deutsch",
volume = "125",
pages = "244--254",
journal = "AVN Allgemeine Vermessungs-Nachrichten",
issn = "0002-5968",
publisher = "VDE Verlag GmbH",
number = "7",
}