| 1. Identity statement | |
| Reference Type | Journal Article |
| Site | marte3.sid.inpe.br |
| Holder Code | isadg {BR SPINPE} ibi 8JMKD3MGPCW/3DT298S |
| Identifier | 6qtX3pFwXQZ3r59YCT/GUdnh |
| Repository | sid.inpe.br/iris@1905/2005/07.28.22.11 (restricted access) |
| Last Update | 2011:01.20.16.01.00 (UTC) administrator |
| Metadata Repository | sid.inpe.br/iris@1905/2005/07.28.22.11.06 |
| Metadata Last Update | 2018:06.06.04.02.42 (UTC) administrator |
| Secondary Key | INPE-5955-PRE/2093 |
| ISSN | 0269-7491 |
| Label | 6043 |
| Citation Key | Padilha:1999:BeMaSo |
| Title | Behaviour of magnetotelluric source fields within the equatorial zone  |
| Year | 1999 |
| Month | May |
| Access Date | 2024, Apr. 28 |
| Secondary Type | PRE PI |
| Number of Files | 1 |
| Size | 745 KiB |
| 2. Context | |
| Author | Padilha, Antonio Lopes |
| Group | DGE-INPE-MCT-BR |
| Affiliation | Instituto Nacional de Pesquisas Espaciais (INPE) |
| Author e-Mail Address | padilha@dge.inpe.br |
| Journal | Environmental Pollution |
| Volume | 51 |
| Number | 10 |
| Pages | 1119-1125 |
| History (UTC) | 2008-06-09 16:40:53 :: administrator -> banon :: 2010-05-11 15:34:57 :: banon -> jefferson :: 2011-01-20 16:01:00 :: jefferson -> banon :: 1999 2012-09-27 18:10:43 :: banon -> administrator :: 1999 2018-06-06 04:02:42 :: administrator -> marciana :: 1999 |
| 3. Content and structure | |
| Is the master or a copy? | is the master |
| Content Stage | completed |
| Transferable | 1 |
| Content Type | External Contribution |
| Keywords | geofísica espacial Brasil eletrojatos equatorial pesquisa magnética (perfis magnetoteluricos) Brazil equatorial electrojet magnetic surveys (magnetotelluric profiling) |
| Abstract | It is well known that equatorial electrojet (EEJ) currents can significantly affect the geomagnetic variations. However, in a recent study (Padilha et al, 1997) it was observed that magnetotelluric (MT) soundings carried out across the dip equator in the Brazilian equatorial zone were not affected significantly due to EEJ currents. By using new results from geomagnetic variation signals, measured simultaneously to the MT experiment at a chain of equatorial and mid-latitude stations, an attempt is made here to explain the MT results in terms of the behaviour of the primary inducing field during the survey. Most of the analysis is performed by considering a single frequency (0.885 mHz), representative of the MT frequency interval. It is observed that the amplitude of the geomagnetic variations appears horizontally homogeneous within the study area (from -3 degrees to +3 degrees of geomagnetic latitude), indicating that the primary field in the analysed frequency range may be considered sufficiently uniform in the horizontal direction thus satisfying the Tikhonov-Cagniard plane-wave criterion. The same geomagnetic data also show that, if any EEJ source effect exists, it would be restricted to the transition zone (between 3 degrees and 5 degrees, at both sides of the dip equator). Dmitriev-Berdichevsky's constraints calculated at two different frequencies and a modelling exercise using EEJ parameters derived from a magnetometer array were able to explain the MT observations and have shown that source effects would just appear in frequencies lower than 1 mHz (resistive regions) and 0.1 mHz (conductive regions). Considering the characteristics of propagation and amplification of geomagnetic variations at the equatorial zone it is concluded that EEJ currents could be used as a source for lithospheric MT studies in these regions. |
| Area | CEA |
| Arrangement | urlib.net > BDMCI > Fonds > Produção anterior à 2021 > DIDGE > Behaviour of magnetotelluric... |
| doc Directory Content | access |
| source Directory Content | there are no files |
| agreement Directory Content | there are no files |
| 4. Conditions of access and use | |
| Language | en |
| Target File | publicacao.pdf |
| User Group | administrator banon jefferson |
| Visibility | shown |
| Archiving Policy | denypublisher denyfinaldraft24 |
| Read Permission | deny from all and allow from 150.163 |
| 5. Allied materials | |
| Next Higher Units | 8JMKD3MGPCW/3EU29DP |
| Dissemination | WEBSCI; PORTALCAPES. |
| Host Collection | sid.inpe.br/banon/2001/04.03.15.36 |
| 6. Notes | |
| Empty Fields | alternatejournal archivist callnumber copyholder copyright creatorhistory descriptionlevel documentstage doi e-mailaddress format isbn lineage mark mirrorrepository nextedition notes orcid parameterlist parentrepositories previousedition previouslowerunit progress project readergroup resumeid rightsholder schedulinginformation secondarydate secondarymark session shorttitle sponsor subject tertiarymark tertiarytype typeofwork url versiontype |
| 7. Description control | |
| e-Mail (login) | marciana |
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