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Extracting volatiles from lunar regolith for analysis or utilization is one of the most important aspects of future lunar exploration. However, the low thermal conductivity of lunar regolith poses a challenge. Here, we conduct simulations to analyze the heat and mass transfer processes within the sample inside the oven. We identify three main factors affecting oven heat‐up rate: water ice content (WIC) in the regolith, oven diameter, and power supply. Taking these factors into account, we devise an oven design and apply it to three case studies: (a) assessing water ice and isotopic composition in Permanently Shadowed Regions, akin to Chang'e‐7 mini‐fly probe missions; (b) measuring noble gases, as Chang'e‐7 and Luna‐27 landers; and (c) large‐scale in‐situ resources utilization (ISRU). The simulation results indicate that water ice can be extracted using sufficiently high heating power without issues. However, the complete extraction of noble gases is challenging and may require alternative heating methods. For ISRU purposes, large ovens can be subdivided into smaller ones by adding internal structures, for example, honeycomb, to improve the heat‐up rate by at least 1.5 times. Additionally, we find that the oven can serve as a scientific payload for WIC measurement using the heating curve. A flowchart of this new WIC measurement method is provided, offering an alternative method to mass spectrometry or spectroscopy measurements. Key Points: The paper presents a realistic heating oven design for in‐situ extraction of volatiles from lunar regolithThree factors controlling the oven's heat‐up rate are water ice content (WIC) in regolith, oven diameter, and power supplyThe oven can serve as a scientific payload for measuring the WIC in regolith based on the heating curve [ABSTRACT FROM AUTHOR]

The article focuses on findings of a study on early paleozoic magmatism and crustal evolution in the North Qinling Orogen. Topics include multi-phase tectonic-magmatic events found in North Qinling orogenic belt; chronlogical and chemical evidence for the evolution of the basement and tectonic provenance of the Qinling orogenic belt; and a comparison with the magmatism and crustal evolution of the adjacent terrains.

Determining the types of lunar mare basalts (i.e., very low-Ti, low-Ti, and high-Ti) is important for constraining the chemical composition of the lunar mantle and the possible dynamic processes during their formation. To date, bulk-rock analysis and inversion of Ti abundances in olivine and plagioclase indicate the Chang'e-5 (CE5) basalts as the low-Ti type. In contrast, the chemical composition of pyroxenes, which is also used to distinguish basalt types, shows an affinity to the high-Ti type as inferred from the Fe#-Ti# relationship. To investigate this discrepancy, we reassessed the classification of CE5 basalts by combining previously available pyroxene composition and the newly obtained data for CE5 basalts and a lunar basalt meteorite (NWA 4898). Our results demonstrate a consistent decrease in Cr 2 O 3 content within pyroxenes from ∼0.8 wt% to nearly zero with magmatic differentiation, diverging from high-Ti basalts but resembling the Apollo low-Ti basalts. Approximately half of the CE5 pyroxenes with Mg# < 45 have lower Cr 2 O 3 content compared to both the Apollo low- and high-Ti basalts. In contrast, TiO 2 content in CE5 pyroxenes is higher than in most low-Ti basalts, but similar to high-Ti basalts, especially at Mg# between 60 and 40. However, such a high Ti signature is unlikely originated from a high-Ti source but more likely evolved from a low-Ti source wherein the Ti content in the melt significantly increased before eruption. This interpretation is supported by the increase-decrease of TiO 2 trend in pyroxene grains from lunar meteorites NWA 4898, NWA 4734, and LAP group. Thus, the relatively lower Cr 2 O 3 content in pyroxenes at Mg# < 45 and the relatively higher TiO 2 content in most pyroxenes ultimately resulted in high Ti# values, but the CE5 pyroxenes still record magmatic differentiation from a low-Ti melt. • Early crystallization before eruption probably increases Ti content in pyroxenes. • The relatively high Ti and low Cr content mainly account for the rise of Ti#. • The high Ti# of CE5 pyroxenes results from magmatic evolution of a low-Ti source. [ABSTRACT FROM AUTHOR]