EARTH DYNAMICS | Magnetics

<body onload="dynAnimation()" background="_themes/earthdyn2/stonbk.jpg" bgcolor="#FFFFFF" text="#000000" link="#003399" vlink="#800000" alink="#666666"><font face="Arial"> <p align="left" style="margin-top: -10; margin-bottom: 0"> <img border="0" src="_borders/logo3.jpg" align="left" width="66" height="87"><font size="7" color="#0000FF"><b><i> </i></b></font><b><i><font size="7" color="#0000FF">EARTH DYNAMICS</font></i></b></p> </font><table border="0" cellpadding="0" cellspacing="0" style="border-collapse: collapse; float:right; position:absolute; left:734; top:-2" width="334" height="93" align="right"> <tr> <td width="334" height="68" valign="top"><font face="Arial"> <p style="margin-bottom: -15" align="center"><b><font color="#0000FF">Providing Consulting Services To</font></b></p> <p align="center"> <b> <font color="#0000FF">The Pacific Northwest Since 1984</font></b></p> <p align="center"> <b>503-227-7659</b></p> </font></td> </tr> </table><font face="Arial"> <blockquote> <p style="margin-top: -15; margin-bottom: 0" align="left"> <b> <font size="4" color="#0000FF">  </font>       Geophysics ● Vibration & Noise ● Rock Mechanics</b></p> </blockquote> <p> </p> <p align="center"> <script language="JavaScript"></script><script language="JavaScript"></script><a href="index.htm" language="JavaScript" onmouseover="if(MSFPhover) document['MSFPnav1'].src=MSFPnav1h.src" onmouseout="if(MSFPhover) document['MSFPnav1'].src=MSFPnav1n.src" target="_top"><img src="_derived/home_cmp_ed-mainpage010_hbtn.gif" width="144" height="46" border="0" alt="Home" align="middle" name="MSFPnav1"></a> <script language="JavaScript"></script><a href="Geophysical_Methods.htm" language="JavaScript" onmouseover="if(MSFPhover) document['MSFPnav2'].src=MSFPnav2h.src" onmouseout="if(MSFPhover) document['MSFPnav2'].src=MSFPnav2n.src" target="_top"><img src="_derived/Geophysical_Methods.htm_cmp_ed-methods-link010_hbtn.gif" width="144" height="46" border="0" alt="Geophysical Methods" align="middle" name="MSFPnav2"></a> <script language="JavaScript"></script><a href="Vibration_&_Acoustic.htm" language="JavaScript" onmouseover="if(MSFPhover) document['MSFPnav3'].src=MSFPnav3h.src" onmouseout="if(MSFPhover) document['MSFPnav3'].src=MSFPnav3n.src" target="_top"><img src="_derived/Vibration_&_Acoustic.htm_cmp_ed-mainpage010_hbtn.gif" width="144" height="46" border="0" alt="Vibration & Acoustic" align="middle" name="MSFPnav3"></a> <script language="JavaScript"></script><a href="Rock_Mechanics.htm" language="JavaScript" onmouseover="if(MSFPhover) document['MSFPnav4'].src=MSFPnav4h.src" onmouseout="if(MSFPhover) document['MSFPnav4'].src=MSFPnav4n.src" target="_top"><img src="_derived/Rock_Mechanics.htm_cmp_ed-mainpage010_hbtn.gif" width="144" height="46" border="0" alt="Rock Mechanics" align="middle" name="MSFPnav4"></a> <script language="JavaScript"></script><a href="Applications.htm" language="JavaScript" onmouseover="if(MSFPhover) document['MSFPnav5'].src=MSFPnav5h.src" onmouseout="if(MSFPhover) document['MSFPnav5'].src=MSFPnav5n.src" target="_top"><img src="_derived/Applications.htm_cmp_ed-mainpage010_hbtn.gif" width="144" height="46" border="0" alt="Applications" align="middle" name="MSFPnav5"></a></p> <p align="center"><img src="_themes/earthdyn2/hline.gif" width="600" height="10"></p> <div align="center"> <center> </font><table border="0" cellpadding="0" cellspacing="0" style="border-collapse: collapse" width="100%"> <tr> <td width="123" height="330" valign="top"><font face="Arial"> <h5 align="left"> <font style="font-size: 9pt"> <a style="font-family: Arial; font-weight:400" dynamicanimation="fpAnimformatRolloverFP1" fprolloverstyle="color: #0000FF" onmouseover="rollIn(this)" onmouseout="rollOut(this)" language="Javascript1.2" href="Ground_Penetrating_Radar.htm"> <font color="#000000">GPR</font></a></font></h5> <p><font style="font-size: 9pt"> <a style="font-family: Arial; color: #000000" target="_top" href="Electrical_Resistivity.htm"> Electrical Resistivity</a></font></p> <p><font style="font-size: 9pt"> <a style="color: #000000" href="Seismic_Refraction.htm">Seismic Refraction</a></font></p> <p><font style="font-size: 9pt"> <a style="color: #000000" href="ReMi_Shear_Wave.htm">ReMi<br>Shear Wave</a></font></p> <p><font style="font-size: 9pt"> <a style="color: #FF0000" href="Magnetics.htm">Magnetics</a></font></p> <p><a href="Electromagnetics.htm"><font style="font-size: 9pt" color="#000000"> Electromagnetics</font></a></p> <p><a href="Gravity.htm"><font style="font-size: 9pt" color="#000000"> Gravity</font></a></p> <p><font style="font-size: 9pt" color="#000000"> <a href="Downhole_Seismic.htm"> <font color="#000000">Downhole Seismic</font></a></font></p> <p><font color="#000000"><span style="font-size: 9pt"> <a href="Crosshole_Sonic_Logging.htm"><font color="#000000">CSL</font></a></span></font></p> <p><a href="Marine_Geophysics.htm"><font color="#000000" style="font-size: 9pt"> Marine<br>Geophysics</font></a></p> </font></td> <td width="900" height="330" valign="top"><font face="Arial"> <p align="center"><b>    <font FACE="Arial" size="4"> MAGNETIC </font></b><font size="4"><b>METHODS</b></font></p> <div align="left"> </font><table border="0" cellpadding="0" cellspacing="0" style="border-collapse: collapse" width="98%"> <tr> <td width="100%"><font face="Arial"> <p align="left">Magnetic surveys can provide information useful for the following applications:</p> </font><table border="0" cellpadding="0" cellspacing="0" width="100%"> <tr><td valign="baseline" width="42"><img src="_themes/earthdyn2/abstrbu2.gif" width="12" height="12" hspace="15" alt="bullet"></td><td valign="top" width="100%"><font face="Arial"><i><b>Site Evaluations:</b></i> <i>Locating buried objects containing ferrous metal such as drums, tanks, unexploded ordinance and utilities.</i></font></td></tr> <tr><td valign="baseline" width="42"><img src="_themes/earthdyn2/abstrbu2.gif" width="12" height="12" hspace="15" alt="bullet"></td><td valign="top" width="100%"><font face="Arial"><i><b>Geologic Surveys:</b> Identifying changes in bedrock or soil conditions, locating faults and/or dikes.</i></font></td></tr> </table><font face="Arial"> <p align="left">Magnetic surveys provide a cost-effective means for quickly providing whole-site or specific-area investigations.  Magnetometers are highly portable, therefore, surveys can be conducted over uneven te<img border="2" src="Gradiometer.jpg" align="left" width="288" height="216">rrain.</p> <p align="left"></p> <p align="left">A magnetic survey accurately measures the earth's magnetic field.  Objects containing ferrous material create local perturbations in the earth's field.  </p> <p class="MsoNormal">A magnetic gradiometer consists of a magnetometer equipped with two sensors.  The sensors are placed in a vertical orientation to measure the vertical gradient in the earth’s magnetic field, or they can be placed in a horizontal configuration to measure the horizontal gradient.  A gradiometer is ideally suited for detection of shallow ferromagnetic material because the gradiometer accentuates the signal from objects which are at shallow depth while ignoring distant features.  In a gradiometer survey, no corrections are needed for diurnal changes in the earth’s magnetic field because the diurnal changes affect both sensors equally.  </p> <p class="MsoNormal"> </p> </font></td> </tr> </table><font face="Arial"> </div> <p class="MsoNormal" align="center"><img border="0" src="MagData.gif" width="665" height="360"></p> <p class="body-txt" align="center"><b>Example of Magnetics Data</b></p> <p> </font></td> </tr> </table><font face="Arial"></center> </div> <p align="center"><img src="_themes/earthdyn2/hline.gif" width="600" height="10"></p> <p align="center" style="margin-bottom: -17; "> <script language="JavaScript"></script><a href="index.htm" language="JavaScript" onmouseover="if(MSFPhover) document['MSFPnav6'].src=MSFPnav6h.src" onmouseout="if(MSFPhover) document['MSFPnav6'].src=MSFPnav6n.src" target="_top"><img src="_derived/home_cmp_ed-global-010_hbtn.gif" width="95" height="20" border="0" alt="Home" align="middle" name="MSFPnav6"></a> <script language="JavaScript"></script><a href="Key_Personnel.htm" language="JavaScript" onmouseover="if(MSFPhover) document['MSFPnav7'].src=MSFPnav7h.src" onmouseout="if(MSFPhover) document['MSFPnav7'].src=MSFPnav7n.src" target="_top"><img src="_derived/Key_Personnel.htm_cmp_ed-global-010_hbtn.gif" width="95" height="20" border="0" alt="Personnel" align="middle" name="MSFPnav7"></a> <script language="JavaScript"></script><a href="Client_List.htm" language="JavaScript" onmouseover="if(MSFPhover) document['MSFPnav8'].src=MSFPnav8h.src" onmouseout="if(MSFPhover) document['MSFPnav8'].src=MSFPnav8n.src" target="_top"><img src="_derived/Client_List.htm_cmp_ed-global-010_hbtn.gif" width="95" height="20" border="0" alt="Client List" align="middle" name="MSFPnav8"></a> <script language="JavaScript"></script><a href="News.htm" language="JavaScript" onmouseover="if(MSFPhover) document['MSFPnav9'].src=MSFPnav9h.src" onmouseout="if(MSFPhover) document['MSFPnav9'].src=MSFPnav9n.src" target="_top"><img src="_derived/News.htm_cmp_ed-global-010_hbtn.gif" width="95" height="20" border="0" alt="News" align="middle" name="MSFPnav9"></a> <script language="JavaScript"></script><a href="Site_Map.htm" language="JavaScript" onmouseover="if(MSFPhover) document['MSFPnav10'].src=MSFPnav10h.src" onmouseout="if(MSFPhover) document['MSFPnav10'].src=MSFPnav10n.src" target="_top"><img src="_derived/Site_Map.htm_cmp_ed-global-010_hbtn.gif" width="95" height="20" border="0" alt="Site Map" align="middle" name="MSFPnav10"></a></p> <p align="center" style="margin-bottom: -17; ">  </p> <p align="center" style="margin-bottom: -17; "> <u><b><i>Contact Information</i></b><i><b><font size="2"><br> </font></b></i></u><font size="2">2284 NW Thurman Street, Portland, Oregon  97210</font></p> <p align="center" style="margin-bottom: -17; margin-top:15"> <font size="2">voice: (503) 227-7659  fax: (503) 227-1074</font></p> <p align="center" style="margin-bottom: -17; margin-top:15">  </p> <p align="center" style="margin-top: 10"> <font size="1">Last modified: March 07, 2008</font></p> </font></body>