<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0120-0283</journal-id>
<journal-title><![CDATA[Boletín de Geología]]></journal-title>
<abbrev-journal-title><![CDATA[Bol. geol.]]></abbrev-journal-title>
<issn>0120-0283</issn>
<publisher>
<publisher-name><![CDATA[Universidad Industrial de Santander]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0120-02832023000200051</article-id>
<article-id pub-id-type="doi">10.18273/revbol.v45n2-2023003</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Aportes a la investigación del sistema geotérmico del volcán Azufral en Colombia mediante modelos 2D de magnetotelúrica]]></article-title>
<article-title xml:lang="en"><![CDATA[Contributions to the investigation of the geothermal system of the Azufral volcano in Colombia through 2D magnetotelluric models]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Rodríguez-Rodríguez]]></surname>
<given-names><![CDATA[Gilbert]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Servicio Geológico Colombiano  ]]></institution>
<addr-line><![CDATA[Bogotá ]]></addr-line>
<country>Colombia</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>08</month>
<year>2023</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>08</month>
<year>2023</year>
</pub-date>
<volume>45</volume>
<numero>2</numero>
<fpage>51</fpage>
<lpage>63</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0120-02832023000200051&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0120-02832023000200051&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0120-02832023000200051&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen Este trabajo presenta la modelación de la estructura resistiva del subsuelo para el área geotérmica del volcán Azufral, de acuerdo con sondeos magnetotelúricos (MT) y a partir del procesamiento de información adquirida en 140 estaciones de MT, cuyos tiempos de registro en promedio fueron de 24 horas, lo que permitió obtener datos de 104 a 10-2 Hz. Se realizaron también 39 sondeos por transitorios (TDEM) para controlar el desplazamiento de static shift. Inversiones 2D han permitido determinar que la estructura resistiva del área se caracteriza por focos de anomalías conductivas entre 1-10 &#937;·m, intermedias entre 10-100 &#937;·m y zonas resistivas con valores &gt;100 &#937;·m. Las anomalías resistivas superficiales con espesores de 200 a 500 m se asociaron a depósitos piroclásticos no alterados, y las profundas, con espesores de más de 4 km al basamento, que en la zona de investigación correspondería con el grupo Diabásico. Las zonas de anomalías conductivas que se extienden lateralmente por toda el área de estudio, con un espesor aproximado de 2 km, se asocian con capas arcillosas que formarían el sello del sistema geotérmico. Las anomalías con valores intermedios pueden deberse a variaciones de la temperatura del sistema geotérmico creando minerales de distinta conductividad como la illita, biotita y clorita, entre otros.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract This work presents the modeling of the resistive structure of the subsoil for the geothermal area of the Azufral Volcano. The structure was adapted according to magnetotelluric soundings (MT) and from the information processing acquired in 140 MT stations, whose average recording times were 24 hours. These allowed to obtain data from 104 to 10-2 Hz and 39 transient soundings (TDEM) have also been carried out to control the displacement of static shift. 2D inversions have made possible to determine that the resistive structure of the area is characterized by focus of conductive anomalies between 1-10 &#937;·m, intermediate between 10-100 &#937;·m and resistive zones with values &gt;100 &#937;·m. The superficial resistive anomalies with thicknesses of 200 to 500 m were associated with unaltered pyroclastic deposits and the deep ones with thicknesses of more than 4 km to the basement, which in the research area would correspond to the Diabasic group. The zones of conductive anomalies, which extend laterally throughout the study area with an approximate thickness of 2 km are associated with clayey layers that would form the seal of the geothermal system. The anomalies with intermediate values may be due to variations in the temperature of the geothermal system, creating minerals of different conductivity such as Illite, biotite, and chlorite, among others.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Magnetotelúrica del volcán Azufral]]></kwd>
<kwd lng="es"><![CDATA[Sistema Geotérmico Azufral]]></kwd>
<kwd lng="es"><![CDATA[TDEM]]></kwd>
<kwd lng="es"><![CDATA[Basamento Grupo Diabásico.]]></kwd>
<kwd lng="en"><![CDATA[Magnetotelluric of Azufral Volcano]]></kwd>
<kwd lng="en"><![CDATA[Azufral Geothermal System]]></kwd>
<kwd lng="en"><![CDATA[TDEM]]></kwd>
<kwd lng="en"><![CDATA[Diabasic Group Basement.]]></kwd>
</kwd-group>
</article-meta>
</front><back>
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