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<p>Conventional surface electromagnetic methods have limitations of a shallow detection depth and low resolution. To increase the detection depth and resolution, borehole–surface electromagnetic methods for electromagnetic three-dimensional observations of the ground, tunnels, and boreholes have been developed. Current borehole receivers only measure a single parameter of the magnetic field component, which does not meet the special requirements of controlled-source electromagnetic (CSEM) methods. This study proposes a borehole electromagnetic receiver that realizes synchronous acquisition of the vertical electric field component in the borehole and the three-axis orthogonal magnetic field components. This receiver uses <span class="inline-formula">Ti</span> electrodes and fluxgate magnetometers (fluxgates) as sensors to acquire electric and magnetic field components. Multi-component comprehensive observation methods that add the electric field component can effectively support the CSEM method, improve detection accuracy, and exhibit a strong potential for detecting deep ore bodies. We conducted laboratory and field experiments to verify the performance of our new borehole electromagnetic receiver. The receiver achieved a magnetic field noise of less than 6 <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M2" display="inline" overflow="scroll" dspmath="mathml"><mrow class="unit"><mi mathvariant="normal">pT</mi><mspace linebreak="nobreak" width="0.125em"/><msup><mi mathvariant="normal">Hz</mi><mrow><mo>-</mo><mn mathvariant="normal">1</mn><mo>/</mo><mn mathvariant="normal">2</mn></mrow></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="49pt" height="17pt" class="svg-formula" dspmath="mathimg" md5hash="2f2fa550d40784f93d758f5f4a3e8ade"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="gi-10-55-2021-ie00001.svg" width="49pt" height="17pt" src="gi-10-55-2021-ie00001.png"/></svg:svg></span></span> at 1 <span class="inline-formula">kHz</span>, and the electric field noise floor was approximately 20 <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mrow class="unit"><mi mathvariant="normal">nV</mi><mspace linebreak="nobreak" width="0.125em"/><msup><mi mathvariant="normal">m</mi><mrow><mo>-</mo><mn mathvariant="normal">1</mn></mrow></msup><mspace linebreak="nobreak" width="0.125em"/><msup><mi mathvariant="normal">Hz</mi><mrow><mo>-</mo><mn mathvariant="normal">1</mn><mo>/</mo><mn mathvariant="normal">2</mn></mrow></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="70pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="25772bc5daf57bdc9f1220b6f917fd28"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="gi-10-55-2021-ie00002.svg" width="70pt" height="14pt" src="gi-10-55-2021-ie00002.png"/></svg:svg></span></span> at 1 <span class="inline-formula">kHz</span>. The <span class="inline-formula">−3 dB</span> electric field bandwidth can reach DC <span class="inline-formula">−10 kHz</span>. The results of our experiments prove that high-quality CSEM signals can be obtained using this new borehole electromagnetic receiver and that the electric field component exhibits sufficient advantages for measuring the vertical component of the electric field.</p>