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Over the past decades, dating inclusions in lithospheric diamonds has advanced from analysing tens of pooled inclusions to single sulphide Re-Os analyses and single silicate Sm-Nd analyses, resulting in a fair global coverage of lithospheric diamond ages (Smit et al. 2022) and linking these to tectonomagmatic events. On the other hand, dating of inclusions in sublithospheric diamonds is incredibly limited, mainly due to the rarity of sulphide inclusions and complex retrogressed Ca-silicate phases in already scarce sublithospheric diamonds. Yet, sublithospheric diamonds are important from both a scientific and economic perspective, representing the deepest pristine samples of Earth’s mantle and some of the most valuable diamonds recovered. Understanding their chemical signatures in a broader geological context requires dating such samples. Here we will review the recent progress in dating inclusions in sublithospheric diamonds and discuss their link to the supercontinent cycle and emplacement history. 

Abstract Subduction related to the ancient supercontinent cycle is poorly constrained by mantle samples. Sublithospheric diamond crystallization records the release of melts from subducting oceanic lithosphere at 300–700 km depths^1,2and is especially suited to tracking the timing and effects of deep mantle processes on supercontinents. Here we show that four isotope systems (Rb–Sr, Sm–Nd, U–Pb and Re–Os) applied to Fe-sulfide and CaSiO₃inclusions within 13 sublithospheric diamonds from Juína (Brazil) and Kankan (Guinea) give broadly overlapping crystallization ages from around 450 to 650 million years ago. The intracratonic location of the diamond deposits on Gondwana and the ages, initial isotopic ratios, and trace element content of the inclusions indicate formation from a peri-Gondwanan subduction system. Preservation of these Neoproterozoic–Palaeozoic sublithospheric diamonds beneath Gondwana until its Cretaceous breakup, coupled with majorite geobarometry^3,4, suggests that they accreted to and were retained in the lithospheric keel for more than 300 Myr during supercontinent migration. We propose that this process of lithosphere growth—with diamonds attached to the supercontinent keel by the diapiric uprise of depleted buoyant material and pieces of slab crust—could have enhanced supercontinent stability. 

Underground Nuclear Astrophysics Experiment in China (JUNA) has been commissioned by taking the advantage of the ultra-low background in Jinping underground lab. High current mA level 400 KV accelerator with an ECR source and BGO detectors were commissioned. JUNA studies directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. In the first quarter of 2021, JUNA performed the direct measurements of 25 Mg(p, γ ) 26 Al, 19 F(p, α ) 16 O, 13 C( α ,n) 16 O and 12 C( α , γ ) 16 O near the Gamow window. The experimental results reflect the potential of JUNA with higher statistics, precision and sensitivity of the data. The preliminary results of JUNA experiment and future plan are given.