The precision and accuracy of 40Ar/39Ar dates are ultimately linked to co‐irradiated reference materials of known age. Here we provide new data from the SK01 sanidine, which was analysed in three different laboratories to evaluate it as a 40Ar/39Ar reference material. Aliquots of 5 mg, incrementally heated in two laboratories, yielded indistinguishable results with a weighted mean age of 27.58 ± 0.06 Ma (95% confidence level). Single‐crystal step heating and single‐crystal total fusion analyses of SK01 sanidine were undertaken in the third laboratory to further test the intracrystalline homogeneity. For the seven step‐heating analyses, six crystals yielded nearly concordant age spectra with 40Ar/39Ar ages ranging from 26.853 ± 0.094 Ma to 26.963 ± 0.067 Ma, whereas one crystal gave an older age of 27.774 ± 0.071 Ma with a slightly discordant age spectrum. Twenty‐three single‐crystal total fusion analyses yielded 40Ar/39Ar ages ranging from 27.070 ± 0.108 Ma to 27.736 ± 0.062 Ma with a dispersion of ~ 3.8%. The older ages from single‐crystal total fusion dates are interpreted to reflect an inherited or excess argon component in some crystals. This is an initial characterisation of the SK01 sanidine, and additional work needs to be conducted to further evaluate the age dispersion so that it can be utilised as a 40Ar/39Ar reference material.

The non-linear reliance of channel steepness on erosion rates can be reconciled by the stochastic-threshold incision model that incorporates river incision threshold and discharge probability distribution into erosion efficiency. Here, we explored the usage of the model in river longitudinal profile inversion, by assuming time-dependent tectonic forcing and a linear exponent that relates channel incision to slope. We developed an analytical solution to the model equation and an inverse scheme to retrieve relative uplift rate history, whose validity was based on the theoretical demonstration on knickpoint preservation. Application of the inverse scheme to the main trunks of the Dadu River basin in the eastern Tibetan Plateau produced a history with two-phase increases in the uplift/incision rates, which is similar to the results from low-temperature thermochronology. Thus, our analytical procedures provide new insights into the link of tectonic uplift and river profile evolution, when channel steepness depends on erosion rates non-linearly.

<p>Cosmogenic noble gas isotope <sup>21</sup>Ne in terrestrial rocks has been used primarily to determine timing and rates of the Earth’s surface evolution. Here we explore the ability of detrital <sup>21</sup>Ne as a provenance tracer, considering that Ne isotopes produced in source rocks could be preserved in minerals over geological time and might be predominant in total Ne inventory of sediments sunk in basins. This ability is predicated on potential source terranes of a given stratigraphic section with distinct neon isotopic signatures. Here we analyze neon isotopes of a well-dated Miocene–Pleistocene sedimentary archives in Kuqa foreland basin of southern Tianshan. The data suggest that the neon isotopic signature,<em> </em>which is expressed as<em> ε</em><em><sub>Ne</sub></em> and defined in this work as the excess <sup>21</sup>Ne/<sup>20</sup>Ne-ratio relative to atmospheric ratio, is stratigraphically sensitive to changes in local source terranes. This result is compatible with U/Pb provenance analysis and also supported by evidences from sandstone petrography and heavy mineral analysis. Influence of other non-source related <sup>21</sup>Ne components in sedimentary archives on sensitivity of <em>ε</em><em><sub>Ne </sub></em>has proven to be negligible. Furthermore, the integrated stratigraphic signatures of neon isotope and U/Pb age permit the detection of differential erosion in drainage basin, by which the tectonic or climatic effects on geomorphic evolution could be deciphered.</p>