ÿþ<HTML> <HEAD> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> <META NAME="GENERATOR" CONTENT="Mozilla/4.05 (Macintosh; I; PPC) [Netscape]"> <TITLE>Research Interests</TITLE> </HEAD> <BODY BACKGROUND="smoke1.jpg" BGCOLOR="silver" LINK="#0000FF" VLINK="#6B21B0" ALINK="#E5DB1A"> <BR> <P ALIGN="center"><B><FONT FACE="Arial" SIZE="+3">RESEARCH INTERESTS</FONT></B></P> <P ALIGN="center" STYLE="margin-left: 15%; margin-right: 15%;"><FONT FACE="Arial" COLOR="#E32D3A" SIZE=+2>I have several currently active research projects, some of them funded by NSF. Below is a brief summary of past and currently active research projects. I am looking for students, so if interested please contact me by email about new projects in Central America and East Africa!</FONT></P> <BR> <HR WIDTH="85%"> <BR> <P><B><I><FONT FACE="Arial" SIZE="+2">New research projects</FONT></I></B></P> &nbsp; <OL TYPE="I"> <LI><P STYLE="margin-left: 10px;"><B><FONT FACE="Arial" SIZE="+1">Degassing fractionation of sulfur isotopes at Erta Ale Volcano, Ethiopia</FONT></B></P></LI> <P STYLE="margin-left: 30px;">My ultimate goal in this study is to develop a consistent model for how sulfur degases from magmas in volcanoes worldwide. Sulfur is one of the most abundant constituents of volcanic gases and is an important component of magmas. It is the <I>most</I> important volcanic gas in terms of climate impact due to the oxidation of sulfur to sulfate aerosols in the atmosphere. Sulfur has recently received a lot of attention due to ideas of geo-engineering where scientists propose to inject large quantities of sulfur into the stratosphere to counterbalance global warming. Therefore, understanding how and in what quantities sulfur degases naturally from magmas at volcanoes is a critical step in evaluating the global sulfur cycle with implications for climate impact as well as evaluating potential consequences of human impacts on the Earth's sulfur budget. In order to address these questions, I am investigating sulfur degassing from a persistently active lava lake at Erta Ale volcano in Ethiopia. This lake is the Earth's longest-lived lava lake and has been persistently active for over 100 years, degassing large quantities of sulfur from a basaltic magma. The isotopic composition of the sulfur in the lava, gas, and aerosols will be analyzed to understand the nature of the sulfur cycle.</P> &nbsp; <LI><P STYLE="margin-left: 10px;"><FONT FACE="Arial" SIZE="+1"><B>Volatiles in the groundwater systems of the Nicoya Peninsula, Costa Rica: tracking subduction zone gases from slab to surface </B><I>(new NSF grant)</I></FONT></P></LI> <P STYLE="margin-left: 30px;">Fluid flow through subduction zones is a fundamental process on Earth. As oceanic plates get subducted, water and other volatiles (i.e. CO<SUB>2</SUB>, N<SUB>2</SUB>) are released into the overlying mantle wedge. These fluids are the primary cause for the melting of the mantle and the production of water-rich magmas that cause explosive volcanic eruptions. In addition, volatiles are either efficiently recycled back to the atmosphere through subduction-related volcanoes (as is the case for N<SUB>2</SUB>) or are potentially carried into the deep mantle (as may be the case for CO<SUB>2</SUB>). The extent of volatile recycling in subduction zones, therefore, has significant bearing on the overall volatile composition of the mantle and the atmosphere. In this project, I am focusing on the Costa Rica subduction zone complex, and hope to produce a dataset of chemical and isotopic compositions of both gases and groundwaters with the aim of understanding details of volatile provenance, flux and temporal variability.</P> <P STYLE="margin-left: 30px;">In addition, several springs will be monitored continuously for gas composition in order to investigate temporal changes related to earthquake activity occurring in the region. Because the fore-arc region of Costa Rica is the location of numerous large earthquakes, I am investigating the relationships between fault localities, the occurrence of cold springs, gas compositions, and earthquake activity, which provides the potential to better understand earthquake processes in this region.</P> &nbsp; <LI><P STYLE="margin-left: 10px;"><FONT FACE="Arial" SIZE="+1"><B>The interaction of magmatic volatiles, faults, and magmatism in the East African Rift Valley: insights from Northern Tanzania and Southern Kenya. </B><I>This new NSF-funded research is in collaboration with geophysics and tectonics.</I></FONT></P></LI> <P STYLE="margin-left: 30px;">The goal of the project is to develop an integrative approach to understanding incipient and youthful rift zones developing in thick continental lithosphere by targeting a portion of the East African Rift system in northern Tanzania and southern Kenya. The development of these rifts is a fundamental plate tectonic process yet the driving forces behind rift initiation and early evolution are tenuously understood. This analysis will utilize:</P> <OL STYLE="margin-left: 30px;"> <LI>field-based mapping of fault system geometries</LI> <LI>3D visualization of magmatic and fault systems in the lithosphere using a broadband seismic array</LI> <LI>sampling of gas emissions from hydrothermal springs along fault systems</LI> <LI>sampling of volcanic products exposed by fault systems for geochronologic analysis</LI> </OL> <P STYLE="margin-left: 30px;">By combining fieldwork, geophysics, geochemistry, and geochronology, I am seeking to formulate a model for rift development and evolution that is integrated across disciplines and to capture multiple facets of the rifting processes. The results of the work will be applicable to rift zone development globally and can thus be integrated into existing plate tectonic models to provide a rationale for why continental breakup is possible.</P></OL> <BR> <HR WIDTH="85%"> <BR> <P><B><I><FONT FACE="Arial" SIZE="+2">Past research projects</FONT></I></B></P> &nbsp; <P STYLE="margin-left: 10px;"><B><FONT FACE="Arial" SIZE="+1">Volatile fluxes from volcanoes  remote sensing of volcanic gas emissions</FONT></B></P> <TABLE COLS=2 WIDTH="100%" HEIGHT="30%"> <TR> <TD> <UL> <LI><FONT FACE="Times">Anatahan Volcano, Marianas: I took part in the response to the first historical eruption (2003), found clues from volatile fluxes, ash leachates and deposits</FONT></LI> <UL> <LI><FONT FACE="Times"><A HREF="anatahan.htm" TARGET="_blank">Anatahan eruption and recent publications</A></FONT></LI> </UL> &nbsp; <LI><FONT FACE="Times">Po&aacute;s Volcano, Costa Rica: used the TEM and SEM to study aerosol composition in the plume</FONT></LI> <UL> <LI><FONT FACE="Times"><A HREF="Poas1.htm"TARGET="_blank">Po&aacute;s plume and recent publication</A></FONT></LI> </UL> &nbsp; <LI><FONT FACE="Times">Masaya Volcano, Nicaragua: testing of mini-DOAS to measure SO<SUB>2</SUB> in plumes</FONT></LI> <UL> <LI><FONT FACE="Times"><A HREF="DOAS.htm"TARGET="_blank">mini-DOAS at Masaya Volcano</A></FONT></LI> </UL> &nbsp; <LI><FONT FACE="Times">Karymsky Volcano, Kamchatka: monitored SO<SUB>2</SUB> flux, an eruption every 30 minutes</FONT></LI> <UL> <LI><FONT FACE="Times"><A HREF="karymsky.htm"TARGET="_blank">SO<SUB>2</SUB> and ash blasts at Karymsky</A></FONT></LI> </UL> </TD> <TD><IMG SRC="Anatahan.JPG" LOWSRC="Anatahan.JPG" BORDER="3" HEIGHT="192" WIDTH="308"> <BR><FONT FACE="Times">First historical eruption of Anatahan, Marianas (May 2003)</TD> </TR> <TR> <TD></TD> <TD></TD> </TR> </TABLE> <P STYLE="margin-left: 10px;"><FONT SIZE="+1" FACE="Arial"><B>Magmatic volatiles  direct sampling of gases</B></FONT></P> <UL> <LI><FONT FACE="Times">Oldoinyo Lengai, East African Rift: study of mantle volatiles and the eruption of carbonatite lavas</FONT></LI> <UL> <LI><FONT FACE="Times"><A HREF="lengai.htm"TARGET="_blank">sampling carbonatite lavas</A></FONT></LI> </UL> &nbsp; <LI><FONT FACE="Times">Kudryavy Volcano, Kurile Islands: investigated sources of CO<SUB>2</SUB>, N<SUB>2</SUB>, He and H<SUB>2</SUB>O in subduction zone volcanoes, using COSPEC and also sampling >900&deg;C gases!</FONT></LI> <UL> <LI><FONT FACE="Times"><A HREF="kudryavy.htm"TARGET="_blank">papers on Kudryavy and pictures</A></FONT></LI> </UL></UL> &nbsp; <P STYLE="margin-left: 10px;"><FONT SIZE="+1" FACE="Arial"><B>Along-arc variations of magmatic volatiles  how do volatile compositions reflect subduction zone processes?</B></FONT></P> <UL> <UL> <LI><FONT FACE="Times"><A HREF="America.htm"TARGET="_blank">the Central America volcanic arc</A></FONT></LI> <LI><FONT FACE="Times"><A HREF="Sangihe.htm"TARGET="_blank">the Sangihe volcanic arc, Sulawesi, Indonesia</A></FONT></LI> </UL> </UL> &nbsp; <P STYLE="margin-left: 10px;"><FONT SIZE="+1" FACE="Arial"><B>Constraining the volatile composition of the Icelandic mantle  NSF-funded work on N-isotopes from hot springs, phenocrysts and glasses. </B><I> The field work is completed but projects on the phenocrysts are still on-going.</I></FONT></P> <BR> <HR WIDTH="85%"> <BR> <P><B><I><FONT FACE="Arial" SIZE="+2">Links</FONT></I></B></P> &nbsp; <B><FONT SIZE="+1" FACE="Arial">Some links for further information on other past field areas:</FONT></B> <UL> <LI><A NAME="Colombia"></A><FONT FACE="Times"><B>Colombia: &nbsp;</B><A HREF="http://mafalda.univalle.edu.co/~ovp/volcanes.html#Galeras">Galeras</A>, Purace, Cumbal, and Ruiz Volcanoes</FONT></LI> &nbsp; <LI><A NAME="Mexico"></A><FONT FACE="Times"><B>Mexico: &nbsp;</B><A HREF="http://www.geo.mtu.edu/volcanoes/mexico/popocatepetl/updates/">Popocat&eacute;petl</A> and <A HREF="http://volcano.und.nodak.edu/vwdocs/volc_images/north_america/mexico/elch1.html">El Chich&oacute;n</A> Volcanoes</FONT></LI> &nbsp; <LI><A NAME="Russia"></A><FONT FACE="Times"><B>Russia: &nbsp;</B><A HREF="http://volcano.und.nodak.edu/vwdocs/volc_images/north_asia/kuriles.html">Kudryavy Volcano in the Kurile Islands</A></FONT></LI> &nbsp; <LI><A NAME="Indonesia"></A><FONT FACE="Times"><B>Indonesia: &nbsp;</B><A HREF="http://volcano.und.nodak.edu/vwdocs/volc_images/southeast_asia/indonesia/papandayan.html">Papandayan</A> and <A HREF="http://volcano.und.nodak.edu/vwdocs/volc_images/southeast_asia/ijen.html">Kawah Ijen Volcanoes</A> in Java</FONT></LI> &nbsp; <LI><A NAME="Philippines"></A><FONT FACE="Times"><B>Philippines: &nbsp;</B><A HREF="http://www.jpl.nasa.gov/radar/sircxsar/taal.html">Taal Volcano</A> in Luz&oacute;n</FONT></LI> </UL> <BR> <HR WIDTH="100%"> <TABLE ALIGN=RIGHT BORDER=0 > <TR> <TD>Tobias P. Fischer</TD> <TD>&nbsp;</TD> </TR> <TR> <TD>Research Interests, updated 28 Oct 2011</TD> <TD>&nbsp;</TD> </TR> </TABLE> </BODY> </HTML>