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<p>Apatite and zircon (U–Th) <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M3" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="e653eaf840568ee76bb20ba3bf368ae0"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="gchron-3-351-2021-ie00004.svg" width="8pt" height="14pt" src="gchron-3-351-2021-ie00004.png"/></svg:svg></span></span> He thermochronological data are obtained through a combination of crystal selection, He content measurement by crystal heating with analysis using noble gas mass spectrometry, and measurement of U, Th, and Sm contents by crystal dissolution as well as solution analysis using inductively coupled plasma mass spectrometry (ICP-MS). This contribution documents the methods for helium thermochronology used at the GEOPS laboratory, Paris-Saclay University, between 2007 and the present that allow apatite and zircon (U–Th) <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="57ee8123d9c9aefcf23d9c7f6463c158"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="gchron-3-351-2021-ie00005.svg" width="8pt" height="14pt" src="gchron-3-351-2021-ie00005.png"/></svg:svg></span></span> He data to be obtained with precision. More specifically, we show that the He content can be determined with precision (at 5 %) and accuracy using a calibration of the He sensitivity based on the Durango apatite, and its use also appears crucial to check for He and U–Th–Sm analytical problems. The Durango apatite used as a standard is therefore a suitable mineral to perform precise He calibration and yields (U–Th) <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M5" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="93e47eb16cb371fe6916d3191efc4f1d"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="gchron-3-351-2021-ie00006.svg" width="8pt" height="14pt" src="gchron-3-351-2021-ie00006.png"/></svg:svg></span></span> He ages of 31.1 <span class="inline-formula">±</span> 1.4 Ma with an analytical error of less than 5 % (1<span class="inline-formula"><i>σ</i></span>). The (U–Th) <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M8" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="fb147fccdcf98a9911cf3d26a8f6dc33"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="gchron-3-351-2021-ie00007.svg" width="8pt" height="14pt" src="gchron-3-351-2021-ie00007.png"/></svg:svg></span></span> He ages for the Fish Canyon Tuff zircon standard yield a dispersion of about 9 % (1<span class="inline-formula"><i>σ</i></span>) with a mean age of 27.0 <span class="inline-formula">±</span> 2.6 Ma, which is comparable to other laboratories. For the long-term quality control of the (U–Th) <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M11" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="165b352473919034209a9d51d0eaf41d"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="gchron-3-351-2021-ie00008.svg" width="8pt" height="14pt" src="gchron-3-351-2021-ie00008.png"/></svg:svg></span></span> He data, attention is paid to evaluating the drift of He sensitivity and blanks through time as well as that of (U–Th) <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M12" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="6bfc4ae3491d603d986b6e1d0e6866cf"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="gchron-3-351-2021-ie00009.svg" width="8pt" height="14pt" src="gchron-3-351-2021-ie00009.png"/></svg:svg></span></span> He ages and Th <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M13" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="8550e2e9970f84100ffbfa4da4f4f543"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="gchron-3-351-2021-ie00010.svg" width="8pt" height="14pt" src="gchron-3-351-2021-ie00010.png"/></svg:svg></span></span> U ratios (with Sm <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M14" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="539a58614ea8688159b8effbc6d3da8d"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="gchron-3-351-2021-ie00011.svg" width="8pt" height="14pt" src="gchron-3-351-2021-ie00011.png"/></svg:svg></span></span> Th when possible), all relying on the use of Durango apatite and Fish Canyon Tuff zircon as standards.</p>