THE WORLD STRESS MAP PROJECT / EARTH SYSTEM MANAGEMENT

THE WORLD STRESS MAP PROJECT / EARTH SYSTEM MANAGEMENT

Postby salsinawi » Mon Mar 05, 2007 8:43 pm

http://www-wsm.physik.uni-karlsruhe.de/ ... frame.html


THE WORLD STRESS MAP PROJECT /

A SERVICE FOR EARTH SYSTEM MANAGEMENT



What is the World Stress Map?


The World Stress Map (WSM) is the global repository for contemporary tectonic stress data from the Earth's crust. It was originally compiled by a research group headed by Mary Lou Zoback as part of the International Lithosphere Programm (ILP). Since 1995 the WSM is a research project of the Heidelberg Academy of Sciences and Humanities. The WSM research team is integrated into the Tectonic Stress Group of the Geophysical Institute at the Karlsruhe University. The WSM is a task group of the International Association of Seismology and Physics of the Earth's Interior (IASPEI).

Who uses the WSM data?
The World Stress Map is used by various academic and industrial institutions working in a wide range of Earth science disciplines such as geodynamics, hydrocarbon exploitations and engineering. The main operational areas are:
• Basin modelling
• Tectonic modelling
• Reservoir management
• Stability of mines, tunnels and boreholes
• Fault-slip tendency
• Seismic risk assessment

How do I get the WSM data?
The World Stress Map is an open-access database. It can be downloaded through the Stress Data subsection which also provides details about the data, utilities for data plotting, stress maps for specific regions, and many other useful information.

For comments or suggestions please send an e-mail.
Last update, November 2005, maintenance of this page: Oliver Heidbach


Members and Office Location of the World Stress Map Project
Since 1995 the World Stress Map is a project of the Heidelberg Academy of Sciences and Humanities. The office of the WSM is located at Karlsruhe University, Geophysical Institute.
Head of the research project
Prof. Dr. Friedemann Wenzel e-mail


Executive Secretary
Dr. Oliver Heidbach e-mail


Professor Emeritus
Dr. Karl Fuchs e-mail


Researchers
Dr. Birgit Müller e-mail

Dr. John Reinecker e-mail

Dr. Blanka Sperner e-mail

Dr. Mark Tingay e-mail


PhD and Diploma students

Dipl.-Geophys. Andreas Barth e-mail


Head of the advisory board


Prof. Dr.-Ing. Helmut Kipphan, Heidelberger Druckmaschinen, Heidelberg

Members of the advisory board

Prof. Dr. Egon Althaus, Institute of Petrography and Geochemistry, Karlsruhe
Dr. John Cook, Schlumberger, Cambridge
Prof. Dr. Roy H. Gabrielsen, Dept. of Geology, University of Bergen
Prof. Dr. Domenico Giardini, Institute of Geophysics, ETH Zürich
Prof. Dr. Onno Oncken, GeoForschungsZentrum Potsdam
Prof. Dr. Christoph Reigber, GeoForschungsZentrum Potsdam
Prof. Dr. Markus Rothacher, GeoForschungsZentrum Potsdam
Prof. Dr. Mark D. Zoback, Stanford, California

Office location and contact address
Karlsruhe University, Geophysical Institute
Hertzstr. 16, 76187 Karlsruhe, Germany

Phone: +49-721-608 4558, Fax: +49-721-711 73
e-mail




New Initiative - Present Day Stress in Sedimentary Basins

As part of our ongoing commitment to helping all users of present day stress data, the WSM project has now commenced a new major initiative to improve its services for the petroleum industry. The key components of this WSM initiative on present day stress in sedimentary basins are:

•expanding the WSM database in petroleum provinces worldwide,
•actively promoting the relevance of present day stress for petroleum exploration and development,
•providing a dedicated point of contact for advice and assistance on petroleum geomechanics issues,
•offering low-cost interpretation of present day stress orientations from borehole data,
•undertaking focused research on petroleum geomechanics applications from basin to wellbore scale, and
•investigating new techniques for stress analysis in the oil-patch.
The ultimate ambition of this initiative is to compile detailed stress maps of all petroleum provinces worldwide, thus creating an invaluable resource for all petroleum scientists and engineers. For more details on the WSM initiative present day stress in sedimentary basins download our one-page proposal.

Stress Data of the WSM

World Stress Map database

The WSM is the global database of contemporary tectonic stress of the Earth's crust. Its uniformity and quality is guaranteed through:
•quality ranking of the data according to international standards
•standardized regime assignment

The WSM merges data which otherwise would be fragmented in separate, often inaccessible archives. It provides the long-term preservation of tectonic stress data from physical loss of data carriers or organizational problems of data storage.

Types of stress indicators

In the World Stress Map different types of stress indicators are used to determine the tectonic stress orientation. They are grouped into four categories:


• Earthquake focal mechanisms
• Well bore breakouts and drilling-induced fractures
• In-situ stress measurements (overcoring, hydraulic fracturing, borehole slotter)
• Young geologic data (from fault-slip analysis and volcanic vent alignments)

For more details about the stress data, the structure of the database, and the access to the data please select the respective submenu. If you want to create your own stress map please use our online software tool CASMO. Since the WSM is an open-access, non-profit project we always need your support. Your contribution of new stress data is needed in order to extend the database. For more details on our contribution policy, please go to the submenu contributions.

Stress Maps of the WSM 2005 release

If you use the stress maps or data in your publications, please, do not forget to quote the WSM database. As the WSM database is exclusively available via internet, the citation in the reference list should look like the following:

Reinecker, J., Heidbach, O., Tingay, M., Sperner, B. & Müller, B. (2005):

The release 2005 of the World Stress Map (available online at www.world-stress-map.org)

The stress maps display the orientations of the maximum horizontal compressive stress SH. The length of the stress symbols represents the data quality, with A being the best quality. Quality A data are assumed to record the orientation of SH to within 10°-15°, quality B data to within 15°-20°, and quality C data to within 25°. Quality D data are considered to give questionable tectonic stress orientations (Zoback, 1992; Sperner et al., 2003).

The tectonic regimes are NF for normal faulting, SS for strike-slip faulting, TF for thrust faulting, and U for an unknown regime. FMS data which are flagged as PBEs are not included in these maps.

The stress maps were created using the Generic Mapping Tools GMT of Paul Wessel and Walter H.F. Smith (Wessel & Smith, 1991). Plate boundaries are by courtesy of Peter Bird (Bird, 2003) and can be downloaded from his ftp-site.
Maps of the release 2005 are available for the following regions:

• World
• Europe
• America
• Africa
• Asia
• Australia

You can create your own stress maps by using our online tool CASMO or by downloading our interactive software tool CASMI (equipped with a graphical user interface).

Please, if you download a map for further use, send us an e-mail. Your feedback will help us to improve our service and demonstrates the people who finance the project that the WSM website is useful and used.
Current and Completed Projects of the World Stress Map Research Team
Stress Data of the WSM

World Stress Map database

The WSM is the global database of contemporary tectonic stress of the Earth's crust. Its uniformity and quality is guaranteed through:

•quality ranking of the data according to international standards
•standardized regime assignment

The WSM merges data which otherwise would be fragmented in separate, often inaccessible archives. It provides the long-term preservation of tectonic stress data from physical loss of data carriers or organizational problems of data storage.
Types of stress indicators
In the World Stress Map different types of stress indicators are used to determine the tectonic stress orientation. They are grouped into four categories:


• Earthquake focal mechanisms
• Well bore breakouts and drilling-induced fractures
• In-situ stress measurements (overcoring, hydraulic fracturing, borehole slotter)
• Young geologic data (from fault-slip analysis and volcanic vent alignments)

For more details about the stress data, the structure of the database, and the access to the data please select the respective submenu. If you want to create your own stress map please use our online software tool CASMO. Since the WSM is an open-access, non-profit project we always need your support. Your contribution of new stress data is needed in order to extend the database. For more details on our contribution policy, please go to the submenu contributions.

Current projects

Stress inversion from broadband seismology networks
(PhD thesis, since 2003, Andreas Barth, Friedemann Wenzel)
Stress directions can be derived from focal mechanism analysis. However, for the majority of small, regionally detectable events, no focal mechanism solution is available. This study investigates in how far fault plane solutions from earthquakes with Mw as small as 4 can be derived using a minimum of 3-component broadband seismometer stations.

Focal mechanism solutions from plate boundary events
(Oliver Heidbach, John Reinecker)
An earthquake focal mechanism solution always has the P- and T-axes at 45° to the fault plane. Frequently, the P-B-T axes are assumed to coincide with the principal stress orientations. However, if friction along the fault is small (e.g. at weak plate boundaries), there can be a considerable difference between the P-B-T axes and the principal stress orientations. This study investigates how to differentiate between weak- and strong-fault earthquakes by comparing the slip vector of the earthquake with the direction of relative plate motion.

3D finite-element modelling of crustal fracture networks in the Coso region, California, USA
(PhD thesis, since 2003, Andreas Eckert, Peter Connolly)
The stress field of the Coso geothermal field is modelled with a 3D finite-element approach. The model incorporates contact surfaces to represent the fault system and uses elastic rheology with given slip on the faults as boundary conditions. It also considers the thermally induced stresses and its implications for thermal cracking. The thesis investigates the location and distribution of different fracture types and the likelihood of their reactivation as well as new fracture generation.

CHEVRON-TEXACO - Stress modelling of thin stratigraphic layers
(Peter Connolly, Jose Dirkzwager)
Sedimentary packages within reservoirs are frequently characterized by high aspect ratios (thickness is several orders less than the areal extent). This study investigated the stress and fracturing conditions if this sedimentary geometry is cut by e.g. fault structures or diapirs.

Recent stress field and geodynamics of Romania (CRC 461 - Project A6)
(Oliver Heidbach, Birgit Müller, Blanka Sperner, Friedemann Wenzel)
The project is part of the Collaborative Research Center "Strong Earthquakes" (CRC 461). The stress field of Romania is documented by focal mechanism solutions from earthquakes at crustal and intermediate depths (down to 200 km), and by borehole breakout data from the Transylvanian basin and the Carpathian foreland. The stress field is influenced by local effects caused by a seismically active slab subducted during Miocene, by topographic effects of the rising Carpathian mountains in combination with the subsiding foredeep, and by large-scale fault zones. The objective of this project is to understand the stress conditions within and above the subducted slab, and the degree of coupling between slab and crust. For further information, please visit the webpages of project A6.


Completed projects

Numerical modelling of stress relaxation after the 2001 Mw=8.4 earthquake in South Peru
(Diploma thesis, 2005, Tobias Hergert, Oliver Heidbach)
The velocity solution of the GPS station in Arequipa recorded the inter-, co-, and postseismic displacements caused by the Mw=8.4 event of Juni 2001 in South Peru. This study investigated whether the postseismic effects can be explained by stress relaxation processes in the lower crust and the upper mantle. Our results from a 2D finite-element model with non-linear, temperature-dependent creep rheology support this hypothesis.

DGMK Tight Gas project 593-5
(Phase 1, 2004, Birgit Müller, Peter Connolly)
This project investigated the influence of salt domes and faults on the local stress pattern. It consisted of a compilation of stress data in northern Germany and finite-elment modelling to determine the variation of stress magnitudes and orientations around tectonic structures such as salt diapirs and faults. Project 593-5 was part of the Tight Gas Reservoirs Research Program of the DGMK. The DGMK is the "German Society for Petroleum and Coal Science and Technology".

Contemporary tectonic stress derived from oriented 6-arm caliper logs
(Diploma thesis, 2003, Diana Wagner, Birgit Müller)
The use of oriented 6-arm caliper tools for borehole geometry analysis, and thus the determination of stress orientations, requires stacking of the data for a number of depth sections. Since the tool is frequently not positioned in the centre of the borehole, stacking requires to correct for this off-centre position. The thesis contains (a) the test of different correction methods of off-centre effects, (b) the implementation of a software tool to analyse oriented 6-arm caliper data, and (c) the application to real data.

Stress data compilation in the Dead Sea fault region and Coulomb failure stress changes based on historical seismicity
(Diploma thesis, 2003, Sonja Greve, Oliver Heidbach)
We investigated the hypothesis of earthquake triggering due to stress changes during a sequence of historical earthquakes over the last 2700 years in the Dead Sea region. The stress field changes were modelled with a boundary-element approach. The results of the Coulomb-failure-stress-change analysis show that static stress changes have only a minor influence on earthquake triggering in the Dead Sea region.

2D finite-element modelling of crustal fracture networks in the Coso region, California, USA

(Diploma thesis, 2003, Andreas Eckert, Peter Connolly)
The Coso geothermal field is located in a complex tectonic setting including a large number of active faults. A 2D finite-element approach with elastic properties was implemented to model the stress field with given slip along the faults as boundary conditions. The thesis investigated the location and distribution of different fracture types and the likelihood of their reactivation as well as new fracture generation.

Modelling the stress field changes occurring in response to the Albstadt shear zone earthquake sequence 1911-1978
(Diploma thesis, 2002, Angela Sachse, John Reinecker, Oliver Heidbach)
We investigated a possible triggering of the earthquakes at the Albstadt shear zone in South Germany between 1911 and 1978. The stress field changes were modelled with a 3D finite-element approach. The results show that the north- and upward trend of the events coincides with regions where the change of Coulomb failure stress is positive, i.e. triggering of the events is possible.


Disclaimer

Information at this site is general information provided as part of World Stress Map project's role in publishing its activities and disseminating information. We aim to ensure that all information we maintain is accurate, current and fit for the purpose intended. Because the World Stress Map (WSM) team must rely on information provided by others, it makes no guarantees, expressed or implied, as to the accuracy of the data, opinions, interpretations, conclusions, or recommendations contained herein. By using this information the user agrees to release and indemnify the WSM team from any liability for injury, loss, damages, or expenses resulting therefrom, even if caused by the negligence of the WSM team.

Links and frames connecting this site with other sites are for convenience only and do not mean that the WSM team endorses or approves them. We cannot guarantee that these links will work all of the time and we have no control over the availability of linked pages.

Generally it is the responsibility of the user to make their own decisions about the accuracy, currency, reliability and correctness of information found in this database and at sites linked from this web site.

Privacy Policy

World Stress Map project's website does not store or capture personal information of the users, but merely logs the IP addresses which are automatically recognised by the web server. We do not use cookies for collecting user information from the site and we will not collect any information about users except that required for system administration of the web server.

This privacy policy only covers World Stress Map project's website at www.world-stress-map.org. Other links within this site to other websites are not covered by this policy.

Copyright Statement

The World Stress Map project and the Heidelberg Academy of Sciences and Humanities own copyright of the material available at this site, unless otherwise stated. All rights reserved.
The copyright of software used or published on the WSM web server and sites varies. For details on the copyright of individual software please contact Dr. Oliver Heidbach.




Further information and requests should be addressed to:

World Stress Map Project
c/o Dr. Oliver Heidbach
Karlsruhe University
Geophysical Institute
Hertzstr. 16
76187 Karlsruhe
Germany
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