Working Group I.2 of IAGA - Electromagnetic Induction in the Earth ================================================================== Electronic Newsletter #17: May 1997 ----------------------------------- Previous newsletters: enews.Oct92 - 1st enews.Jan93 - 2nd enews.Feb93 - 3rd enews.Oct93 - 4th enews.Feb94 - 5th enews.Mar94 - 6th enews.Jun94 - 7th enews.Aug94 - 8th enews.Sep94 - 9th enews.Jun95 - 10th enews.Oct95 - 11th enews.Dec95 - 12th enews.Jun96 - 13th enews2.Jun96 - 14th enews.Dec96 - 15th enews.Feb97 - 16th enews.May97 - 17th (this one) This is the seventeenth electronic newsletter for our group. A newsletter will be sent around when there is enough material, or a special event about to come up, to warrant distribution. Not all of us in the working group have access to an email address; if you are aware of colleagues who are not likely to receive this newsletter, please give them a paper copy (but chastise them for using trees instead of electrons). Also, please forward this to colleagues who may not yet be on my email list and ask them to forward their address to me. Copies of previous electronic newsletters can be obtained from either the MTNet WWW site or by anonymous ftp login to www.cg.nrcan.gc.ca in directory pub/mtnet/docs. Please submit any comments/articles/news-items/gossip/corrections to jones@cg.nrcan.gc.ca Contents: >>>17.1 IAGA Meeting News >>>17.1.1 Session 1.07 >>>17.1.2 Session 1.08 >>>17.2 IASPEI News >>>17.3 Rho+ released >>>17.4 Address Update request >>>17.5 MTNet news >>>17.5.1 MTNet Usage statistics >>>Appendix: Email list IMPORTANT DEADLINES:.. MAY 30, 1997: Brazilian Geophysical Society abstract deadline MAY 31, 1997: International Sympossium on Geology and Environment abstract deadline -------------------------------------------------------------------------------- >>>17.1 IAGA Meeting News ========================= The 1997 IAGA Scientific Assembly will take place in Uppsala, Sweden, between August 4 - 15, 1997. You can get information from their Web page:- http://www.irfu.se/iaga_97.html. The sessions and accepted abstracts are now also available on-line at that Web site. The sessions of primary interest to EM people are all in the first week, with the exception of the session 5.13 on "Sq and L Studies at Individual Observatories". You will find a timetable of EM sessions on MTNet at URL http://www.cg.NRCan.gc.ca/mtnet/confs/iaga97.html Here is the current timetable for our sessions: Day, Date AM PM EVENING First Week Monday, 4th 7.01 7.01 1st CD & Reception Tuesday, 5th 1.08 1.08 Wednesday, 6th 1.04 1.04 WG-BM Thursday, 7th 1.05 Friday, 8th 1.06 1.06 Div I-BM Saturday, 9th 1.07 1.07 Second Week Monday, 11th Tuesday, 12th Wednesday, 13th Assembly Dinner Thursday, 14th 5.13 2nd CD Friday, 15th CD: Conference of Delegates WG-BM: Working Group I.2 Business Meeting Div I-BM: Division I (Internal Fields) Business Meeting >>>17.1.1 Session 1.07 ====================== [submitted by Phil Wannamaker] We have decided to have all papers presented as posters, with each author giving a 5 min. introduction (4 min. + 1 min. for questions). A maximum of 3 viewgraphs or slides may be used in the oral intro. A complete listing of papers in their order of presentation is appended below. 1. Graphite in the Earth Crust and Evolution of the Lithosphere Electrical Conductivity A A Zhamaletdinov ( Geological Institute, Kola Science Centre, Russian Academy of Sciences, 184200 Apatity, Russia) zham@ksc-gi.murmansk.su -------------- 2. Water in the Crust and Melt in the Asthenosphere Inferred from EM Studies L Vanyan (Shirshov Institute of Ocenology, Moscow 117218 Russia) vanyan@geo.sio.rssi.ru -------------- 3. Electromagnetic Images of Subduction Zones and Tectonic Implications G Schwarz (Sveriges Geologiska Undersoekning, Box 670, S-751 28 Uppsala, Sweden) gerhard@sgu.se -------------- 4. Magnetotelluric Soundings on the Hikurangi Margin, New Zealand M R Ingham (Institute of Geophysics, Victoria University, Wellington, New Zealand), and D McKnight (Inst. Geol. & Nucl. Sci., P O Box 1320, Wellington New Zealand) d.mcknight@gns.cri.nz -------------- 5. Magnetotelluric Investigation of the Continent-Continent Plate Boundary of the South Island of New Zealand P E Wannamaker, J A Stodt (University of Utah/EGI, Salt Lake City, USA) G R Jiracek (San Diego State Univ., San Diego, USA), G Caldwell and D McKnight (Inst. Geol. Nucl. Sci., Wellington, New Zealand) pewanna@mines.utah.edu -------------- 6. Resistivity Cross-section of Usu Volcano, Hokkaido, Japan Y Ogawa, N Matsushima, S Takakura (Geological Survey of Japan, 1-1-3 Higashi, Tsukuba, Ibaraki, Japan), H Oshima, M Ustugi, K Hirano, M Iagrashi, T Doi (Dept. of Earth and Planet. Sci., Hokkaido Univ., Sapporo, Hokkaido 060, Japan) oga@gsj.go.jp -------------- 7. Electromagnetic Imaging of Active Faults in the Awaji Island, Japan S Takakura (Geological Survey of Japan, 1-1-3 Higashi, Tsukuba, Ibaraki, Japan) shin@gsj.go.jp -------------- 8. Resistivity Modeling of the Transient EM Data Measured Around Unzen Volcano, SW Japan W Kanda, H Utada and T Kagiyama (Earthquake Research Institute, Univ. of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Japan), Y Tanaka (Beppu Geophysical Research Lab., Faculty of Science, Kyoto Univ., Noguchibaru, Beppu, Oita 874, Japan) kanda@utada-sun.eri.u-tokyo.ac.jp -------------- 9. AMT Survey of Norikura Volcano in the Central Japan K Fujita (Dept. of Earth and Planet. Sci., Kobe Univ., Nada, Kobe 657, Japan), Y Ogawa (Geological Survey of Japan, 1-1-3 Higashi, Tsukuba, Ibaraki, Japan), S Yamaguichi (Dept. E.P.S., Kobe Univ.), M. Ichiki (Kyoto Univ., Gokasho, Uji, Kyoto 611, Japan), Y. Makino (Dept. E.P.S., Kobe Univ.). -------------- 10. Electromagnetic Image of Colliding Continents: Magnetotelluric Results from a Survey of the India-Asia Collision Zone at 90 deg East latitude A G Jones (Geological Survey of Canada, Ottawa), J R Booker, M Unsworth, N Wu (Univ. of Washington, Seattle, USA), L Chen, W Wei, H Tan (China University of Geosciences, Beijing) jones@cg.nrcan.gc.ca -------------- 11. The Lithosphere Structure and Uplift Mechanism of the Tibet Plateau >From Magnetotelluric Deep Sounding X R Kong, X B Ma (Institute of Geophysics, Chinese Academy of Sciences, Datun Road A11, 100101 Beijing, China) xrkong@sun.ihep.ac.cn -------------- 12. The electrical structure of the crust and upper mantle beneath Zhangjiakou-Bohai seismotectonic belt and the vicinity G Z Zhao, Z Jiang, G D Liu, J Tang, Y Zhan, T S Liu (Institute of Geology, State Seismological Bureau, Beijing 100029, China) zhaogz@public.bta.net.cn -------------- 13. Nature of Foreland and Hinterland Overthrusting, Sevier Orogenic Belt, Utah and Nevada, U.S.A., Inferred From Magnetotelluric Profiling P E Wannamaker (University of Utah/EGI, 423 Wakara Way, Suite 300, Salt Lake City, USA) pewanna@mines.utah.edu -------------- 14. Electromagnetic Induction Profile (PREPAN95) from the East European Platform (EEP) to the Pannonian Basin A Adam, L Szarka, V Wesztergom (Geodetic and Geophysical Research Institute of the Hungarian Academy of Sciences, H-9401 Sopron, POB 5 Hungary), T Ernst, J Jankowski and W Jozwiak (Institute of Geophysics of Polish Academy of Sciences), M Hvozdara (Institute of Geophysics, Slovak Republic) adam@ggki.hu -------------- 15. MODELLING OF GEOMAGNETIC TRANSFER FUNCTIONS ACROSS CENTRAL EUROPEAN REGION IN TERMS OF INTERNAL CONDUCTIVITY DISTRIBUTION S Kovacikova, V Cerv, J Pek, J Pecova, O Praus (Geophysical Institute AS CR, Bocni II/1401, 141 31 Praha 4, Czech Republic) opr@ig.cas.cz -------------- 16. Some Magnetovariational from a Study Along a Profil at 33deg South Latitude in Argentina E Borzotta, M J Mamani, H G Fournier (Department of Geophysics, IANIGLA, CRICYT, Casilla de Correo 330, 5500 Mendoza, Argentina) cricyt@planet.losandes.com.ar -------------- 17. Lateral Inhomogeneity of the Lower Crustal Conductivity in the Fennoscandian Shield and its effect on the Regional MT Field T Korja (Dept. of Geophysics, Univ. of Uppsala, Uppsala, Sweden), V Kouznetsov, L Vanyan (Shirshov Institute of Ocenology, Moscow 117218 Russia), M Viljakainen (Univ. of Oulu, Inst. of Geoscience and Astronomy, Oulu, Finland) tk@geofys.uu.se -------------- 18. Early Archean Processes Revealed Through Electromagnetic Images of the Slave Craton A G Jones (Geological Survey of Canada), I J Ferguson (University of Manitoba, Winnipeg, Canada) jones@cg.nrcan.gc.ca -------------- 19. The Crust and Mantle Conductivity of the Karelian and Svecofennian Blocks on the Profile Suoyarvy-Vyborg. A A Kovtun, S A Vagin, I L Vardaniants, N P Legenikova, M Yu Smirnov, (Institutes of Physics, State University Uliyanovskaya, 1 Petrodvorets, St. Petersburg, 198904, Russia) smirnov@spock.niif.spb.su -------------- 20. Magnetotelluric and Deep Geomagnetic Soundings in a Hot Spot Area R Nolasco, P Tarits (Universit de Bretagne Occidentale, UMR 'Domaines Oceaniques', BP 809, 6 Avenue Le Gorgeu, F-29285 Brest Cedex, France) maria@univ-brest.fr -------------- 21. Geomagnetic field and vulcanism G P Gregori, V Banzon, R Leonardi (IFA - CNR, p. Sturzo 31, 00144 Roma, Italy), Xiaoqing Gao (Langhou Inst. for Plateau Atmospheric Physics of Academica Sinica, Gansou Prov., PRC) gregori@atmos.ifa.rm.cnr.it -------------- 22. MT and VES of a Young Rift System: the Bogoria/Baringo Half-Graben, Kenya S Hautot, P Tarits (Univ. de Bret. Occid., UMR 'Domaines Oceaniques', BP 809, 6 Avenue Le Gorgeu, F-29285 Brest Cedex, France) p.tarits@univ-brest.fr -------------- 23. Magnetotelluric Studies of the Zambezi Valley, Northern Zimbabwe. D S Bailey, Prof. K A Whaler (Department of Geology & Geophysics, Univ. of Edinburgh, Edinburgh, Scotland), T G Zengeni, O Gwava (Dept. of Physics, Univ. of Zimbabwe, P.O. Box MP 167, Mt. Pleasant, Harare, Zimbabwe) David.Bailey@ed.ac.uk -------------- 24. Magnetotelluric Measurements in Gediz Graben and Surrounding Menderes Massif A Gurer, O M Ilkisik (Department of Geophysical Engineering, 34850, Avcular, Istanbul, Turkey), A T Basokur (Dept of Geophysical Engr., Ankara Univ., Besevler, Ankara, Turkey), C Kaya (MTA, Dept of Geophysical Investigations, Ankara, Turkey) hozdemir@hotmail.com -------------- 25. Magnetotelluric Soundings over the Penninic zone along the NFP-20 East traverse in the Graubnden (eastern Switzerland) M Gurk, P-A Schnegg (Groupe de Geomagnetisme, Universite de Neuchatel, c/o Observatoire Cantonal, 2000 Neuchatel, Switzerland) gurk@on.unine.ch -------------- 26. The Magneto-telluric Method in the Middle Benue Trough Sedimentary Basin of Nigeria S O Ogunade, G C Onyedim and E A Ariyibi (Department of Physics, Obafemi Awolowo Univ., Ile-Ife, Nigeria) sogunade@oauife.edu.ng -------------- 27. GEOELECTRICAL STRUCTURE ACROSS BAY OF BENGAL AND BARREN ISLAND IN ANDAMAN SEA BY USING OCEAN BOTTOM MAGNETOMETERS P B V Subba Rao, B P Singh, P Weidelt (Institute fur Geophysics and Meteorology, Technical University, Braunschweig, Germany), E J Joseph (Ocean Research Institute, Tokyo, Japan) root@iigm0.ernet.i -------------- 28. A MT Survey at the Northwest Part of Chalkidiki Peninsula (N. Greece) A S Savvaidis, G N Tsokas (Laboratory of Geophysics, Department of Geology, Aristotele University of Thessaloniki, Thessaloniki, 540 06, Greece), L B Pedersen (Dept. of Geophysics, Uppsala Univ. Villavagen 16, S-752 36 Uppsala, Sweden), G O Daws (Dept. of Geology and Geophysics, Univ. of Edinburgh, Edinburgh, Scotland) alekos@lesvos.geo.auth.gr -------------- 29. Accordinative Study Between the Vertical Electrial Sounding and TEM Methods for Exploring Groundwater Along Cairo-Alexandria Road (Egypt) A Gh Hassaneen, E A Al-Sayed, S Sh Osman (National Research Institute of Astronomy and Geoph. (NRIAG), Helwan, Cairo, Egypt) Gad@frcu.eun.eg >>>17.1.2 Session 1.08 ====================== All papers to be given as posters, but with a short (3 min) introduction using a maximum of three overhead transparencies only (NO SLIDES), and a maximum of one question. Following that there will be poster viewing time for much of the day, then finally a discussion period at the end of the day led by a panel of people as yet unpicked. The session format is: 08:30 - 08:35 Opening welcome (A.G. Jones & T. Korja) 08:35 - 10:00 Short oral presentations of posters 1 - 20 10:00 - 10:30 Tea/coffee break 10:30 - 11:25 Short oral presentations of posters 21 - 33 11:25 - 11:30 Move to poster room 11:30 - 14:00 Viewing of posters. Authors of ODD numbered posters to be in attendance at their poster (except in the interval 12:30 - 13:30) 14:00 - 15:30 Viewing of posters. Authors of EVEN numbered posters to be in attendance at their poster 15:30 - 15:55 Tea/coffee break 15:55 - 16:00 Move to presentation room 16:00 - 18:00 Panel-led discussion session The posters and the presentation room are physically close. Below are the 33 papers of the session, which will be presented in alphabetical order. 1 The Effect of Non-Stationary Noise on Electromagnetic Response Estimates R J Banks 2 Geomagnetic Borehole Measurements Trough Steel Casing U Barckhausen, E Steveling and J B Stoll 3 Dimensionality Analysis using Mohr Circles and Local Strike Directions form Magnetotelluric Data in Western Turkey M Bayrak, O M Ilkisik, C Kaya, A T Basokur 4 Time Evolution Of The Magnetic And Magnetotelluric Transfer Functions In Central Italy: Possible Correlations With Seismic Activity D. di Mauro, A. Meloni, P. Palangio, T. Ernst, R. Teisseyre 5 A Method for the Interpretation of Three Dimensional Equatorial Fields S Duhau and E A Martinez 6 Induction Studies in Greenland Under Inhomogeneous Source Field Conditions M Engels 7 A Global Three Dimensional Electromagnetic Response Function Estimated From the World Wide Magnetic Observatory Network I Fujii and A Schultz 8 Statistics Instead of Geoelectric Simulation S M Korotaev 9 On Some Inverse Problems In Electromagnetic Methods For Geophysical Investigations S.G.Kostyanev 10 Electromagnetic Induction in a Spherical Earth With the Surface and Deep Inhomogeneities A V Kuvshinov, D B Avdeev and O V Pankratov 11 Geotechnical Site Evaluation Using VLF-EM Radiohm Resistivity Method in Northern Iraq D S Mahmood and M I Alomari 12 Spectral-finite element approach to the 2-D electromagnetic induction in a spherical Earth Zdenek Martinec 13 Ultra long period (30 days - 1 year) geomagnetic depth sounding and the electrical conductivity of the deep mantle N Olsen 14 Magnetometric Investigations for Regional and Local Predicting of the Oil and Gas Bearing Zones of the Earth's Crust in the Dnieper-Donets Trough Orlyuk, M I, Maksymchuk, V Yu 15 Effect of Depth-varying Strike on MT Responses A Osella, Martinelli, C Pomposiello 16 A Wavelet-Transform Technique for the Detection and Processing of Magnetotelluric Data K. V. Paulson, Y. Zhang 17 ACF Hardware-Software Systems for AMT and ELF Soundings M I Pertel, V E Prokofjev, A K Saraev 18 An Estimation of Parameters Characterizing Conductive Properties of the Mantle L.N.Porokhova, D.A.Porokhov, D.Yu.Abramova 19 MT Studies at Sedimentary Basins of Sierras Pampeanas, Argentina. C Pomposiello, A Osella, A Favetto, C Sainato 20 Researhes of Polarization of the ELF Radio Station Electromagnetic Field A K Saraev, P M Kostkin, A B Kocherov 21 EM Response Estimates for Periods from 3 Hours Upwards, Involving Observatories and Observations at Fieldsites U Schmucker 22 The Electromagnetic Fields of the Dipole Sources for 1-D media A N Shevtsov 23 Analysis of Telluric Field Signals as Possible Precursors to Earthquakes. CH Sivaji 24 High Resolution of DC-Signals Through Removing EM-Induction Stoll, J. B. and Bahr, K 25 Local Time Variation of Geomagnetic Transfer Functions M Takeda 26 Geomagnetic and Environmental Inductions on Human Pathogenic Factors. V P Tritakis, P T Nastos, P E Manesiotis,A Bergiannaki,K Psarros, P Paparrigopoulos,K Stefanis, A G Paliatsos 27 Anisotropic Conductivity of the Ocean Crust in NE Pacific Inferred from CSEM Study L.L.Vanyan, Z.Yu.Djatieva 28 Source Effect on Geomagnetic Induction Vectors in the Fennoscandian Auroral Region Viljanen, A 29 A new Approach to Determine Induction Arrow: Extension of the Method by Rikitake and Yokoyama T Watanabe,M Seto, K Yumoto 30 Solving 3D Electromagnetic Induction Problems by the Hybrid Technique Yegorov I.V.(Shirshov Institute of Oceanology, Moscow 117218, Russia) 31 The Numerical Modelling of Electromagnetic Fields Induced by the Global Ocean Circulation Yegorov I.V.,Palshin N.A.,Vanyan L.L 32 The Normal Apparent Resistivity Curve for the Eastern Part of the Baltic Shield in Frequency Range 0.001-1000 Hz A A Zhamaletdinov, A N Shevtsov, A D Tokarev, M I Pertel, P M Parfentjev 33 Two Approaches to the Problem of the Deep Electrical Soundings of the Baltic Shield in the Audiomagnetotelluric Frequency Band A A Zhamaletdinov, A N Shevtsov, A D Tokarev, M I Pertel -------------------------------------------------------------------------------- >>>17.2 IASPEI News =================== [submitted by Steve Park] [Note: This is past the abstract deadline. Its for information purposes] ANNOUNCEMENT IASPEI 97 AUGUST 18-28, 1997 Thessaloniki, Greece The Second Circular for the 29th General Assembly of the International Association of Seismology and Physics of the Earth's Interior is now available in hard copy or on the WWW at http://www.iaspei97.auth.gr and http://www.csd.net/~bergman/iaspei/ At these WWW sites you will also find all the necessary meeting forms (registration, hotel and abstract) which can be submitted electronically or downloaded and mailed. For hard copies of the Second Circular or additional information please send e-mail to iaspei@lesvos.geo.auth.gr or engdahl@gldfs.cr.usgs.gov Alternatively, send your request by fax to 30-31-998528, 30-31-214553, 1-303-273-8450, or 1-303-273-8600. Abstract and early registration deadline: March 31, 1997. We look forward to seeing you at Thessaloniki. LOC IASPEI 97 Geophysical Laboratory Aristotle University of Thessaloniki GR54006 Greece W6 Electromagnetic Signals Related to Tectonic Processes Scope: Tectonic processes, chiefly earthquakes and volcanic eruptions, have reportedly generated electromagnetic signals prior to, during, and after such events. These signals may be associated with either anomalous electric or magnetic fields, or both. Most published reports of such signals lack corroborating measurements of stress, strain, or other geophysical phenomena however, making identification of a mechanism problematic, if not impossible. The conveners would like to encourage papers which illustrate clear examples of anomalous signals, preferably recorded on multiple sensors. Special emphasis should be placed on defining the nature of the anomalous signals, and clear discussion of the identification of cultural noise sources is necessary. All papers should include complete characterization of the experimental apparatus. Laboratory studies and models of source mechanisms are also encouraged, with special emphasis on electromagnetic fields generated by transient fluid flow. Studies of the statistical evaluation of electromagnetic precursors will not be accepted for this session because other sessions will cover this aspect of earthquake prediction. Conveners: S. Park (USA), J. Zschau (Germany), P. Varotsos (Greece) [Prof. Steve Park, Department of Earth Science, University of California, Riverside, Riverside, CA 92521, USA; Tel: 1 714 787 4324; E-mail: magneto@ucrmt.ucr.edu] -------------------------------------------------------------------------------- >>>17.3 Rho+ released ===================== [submitted by John Booker] Rho+ is Parker & Booker's amplitude/phase variant of Parker's D+. Source code, documentation, and test files are now available from MTNet. This program solves exactly the one-dimensional (1D) inverse problem of magnetotellurics given a set of apparent resistivity and phase data. The theory is the same as D+ except that calculations are done in the complex frequency plane on the log of the c response, not c itself (Parker and Booker, PEPI, 98, 269-282 1996). The utility of Rho+ is far broader than simply testing whether an MT data set is acceptably 1D. For instance, Weidelt and Kaikkonen (GJI, 117, 733-748, 1994) have shown that B-polarization (TM) responses fall within the space of all possible 1D responses. More generally, Rho+ provides a way of fitting a response to noisy data that is guaranteed to have a physically acceptable (causal) relationship between resistivity and phase. Although E-polarization (TE) and 3D data, whose phases lie within 0-90 degrees, cannot be guaranteed to have a resistivity-phase relationship that falls within the space spanned by 1D responses, the situations in which they do not are rare enough that it is always worth applying Rho+ as a data consistency check prior to multi-dimensional interpretation. Input data to Rho+ can be mixtures of apparent resistivity and impedance phase at the same or different frequencies; resistivity alone or phase and just one resistivity. The following calculations can be done: (1) compute the best possible fit to the data in the weighted 2-norm sense; (2) calculate the model in the space of positive delta functions (D+) that achieves this minimum misfit; (3) find the upper and lower bound on either resistivity or phase, holding the Chi-squared misfit fixed at some tolerance corresponding to a misfit above the minimum possible; (4) Optimally repair tears in apparent resistivity resulting from different instrumental or site gains in non-overlapping frequency bands. -------------------------------------------------------------------------------- >>>17.4 Address Update request ============================== The working group address list is badly out-of-date. Please check your address on URL http://www.cg.NRCan.gc.ca/mtnet/addresses/addresses.html If there is a correction required, send it to Gwen Mason at mason@cg.nrcan.gc.ca You can do this from the Web page. Please also send notification of any deletions -------------------------------------------------------------------------------- >>>17.5 MTNet news ================== Additions: Rho+: version 2.0 Updated: j2edi: version 2.1 mtmap: version 2.1 >>>17.5.1 MTNet Usage statistics ================================ To March 13, 1997, the most hits were in February 1997 with 23,310 requests for pages. The previous high was 11,711 for May, 1996. Strangely, The early part of the week (Sun-Wed) gets twice the hit-rate of the later part (Thur-Fri). The hourly summary shows near time-independence, which is a reflection of the global appeal of MTNet. The four most active domains are .edu (U.S.A), .jp (Japan), .ca (Canada), and .de (Germany). After the main page, most hits are for the "Downloadable Programs" page. -------------------------------------------------------------------------------- Alan G Jones Ottawa, 1 May, 1997 -------------------------------------------------------------------------------- >>>Appendix: Email list ======================= The list updated to 1 May is available on MTNet at http://www.cg.NRCan.gc.ca/mtnet/email/email.html If you cannot access the WWW and need your own copy, please send me an email.