Qiongying Liu

The Beibuwan Basin is a Cenozoic extensional basin whose Leiqiong region hosts the youngest intraplate volcanic field in South China. Although a mantle plume has been proposed for this magmatism, its location and timing, along with the crustal melting condition, remain controversial. The tectono‐thermal evolution of this basin, critical for understanding geodynamic processes and geothermal genesis, remains poorly constrained. Here we employ a multi‐episodic finite extension model to quantify lithospheric stretching factors, strain rates, and thermal structure along three profiles and 19 wells. Results show total stretching factors ranging from 1.04 to 1.76, with peak strain rates during the Paleocene, middle Eocene, and Oligocene. Basement heat flow increased progressively from 60 to 62.5 mW/m ² at 65 Ma to 67–85.5 mW/m ² at 23.5 Ma, subsequently decreasing to 65–82 mW/m ² at present, indicating incomplete lithospheric thermal equilibration. Present‐day Moho temperatures vary between 534°C and 735°C, with average Curie interface depth and thermal lithospheric thickness of 22 and 78 km, respectively. Mean present‐day mantle heat flow is 45 mW/m ² , constituting 69% of the terrestrial heat flow. Model results indicate that Paleogene extension greatly enhanced mantle heat flow and temperatures, promoting potential crustal melting at 25–35 km depth. Limited anomalous post‐rift subsidence, accompanied by localized uplift during the early Miocene and Quaternary, indicates the presence of hot mantle upwelling that provided an additional heat source. These findings offer geothermal evidence that the interplay between lithospheric extension and hot mantle upwelling drove the late Cenozoic magmatism in the Leiqiong area.

The implementation of the rural revitalization strategy is a major deployment strategy made by the Party Central Committee on the “agriculture-rural areas-peasants” work. As a special industrial form, rural tourism fully conforms to the general standards of the rural revitalization strategy in terms of economy, society, culture, ecology, and other key aspects. Therefore, it is an important driving force and an effective way to solve the “agriculture-rural areas-peasants” problems and to realize the rural revitalization strategy. This study combines the rural revitalization of ethnic villages and rural tourism in former deep poverty areas, and explores the coupling and coordination between rural tourism and rural revitalization. On the basis of consulting the relevant literature and through qualitative and quantitative research methods, an evaluation index system for the coupling and coordination of rural tourism and rural revitalization in ethnic villages in previously deep poverty areas was constructed. Taking Didigu Village in Ebian Yi Autonomous County as a research case, this study analyzed the comprehensive development level, coupling degree and coupling coordination of its rural tourism and rural revitalization system, then selected the factors and indicators which affect the coordinated development of the coupling of rural tourism and rural revitalization in ethnic villages in order to discuss the leading factors which restrict regional development, and finally put forward targeted optimization countermeasures and suggestions. The results show that rural tourism plays a significant role in guiding rural revitalization, and the interaction between rural tourism and rural revitalization is increasingly enhanced, with large room for future growth. For the former deep poverty minority village, the government's policies, funds, talents and technologies for rural revitalization and rural tourism development play an important role in their coupled development. In order to further improve the coupling degree of rural revitalization and rural tourism, one suggestion is that the government should firmly exercise a top-level design function to improve the quality and efficiency of rural revitalization in order to accelerate the revitalization of rural culture and to drive the improvement of rural tourism quality, thus improving the quality of rural tourism and promoting the revitalization of rural areas.

Systematic measurements of water temperature are lacking but useful in understanding the relationship between water temperature and earthquakes. Based on the water temperature data, geological structure, borehole structure, and temperature gradient in the Jinjia well, Southwest China, we systematically analysed the water temperature changes related to earthquakes. The water temperature of the Jinjia well recorded the coseismic changes caused by the Wenchuan M7.9 and Panzhihua M6.1 earthquakes in 2008. We also found abnormal changes in the water temperature, after which moderate to strong earthquakes occurred in the surrounding region. The preseismic abnormal changes of the Jinjia well were rising-recovery (rising to a high value and continuing for a period of time before decreasing or quickly recovering), with the range of 0.007–0.07 °C. The maximum change (0.07 °C) occurred before the M7.9 Wenchuan earthquake in 2008. According to the Molchan error diagram, the most likely time for an earthquake to occur is within approximately 4 months after the water temperature exceeds the threshold temperature. In the Jinjia well, the installation depth of the temperature sensor affected the correlation between the temperature changes and earthquakes with a seismic energy density above 10⁻³ J·m⁻³. The shorter the distance between the sensor and the fault, the higher the probability of water temperature changes related to earthquakes.

Terrestrial heat flow plays an important role in the study of plate tectonics, geothermal resource exploration and earthquake genesis. The measurement of terrestrial heat flow usually utilizes deep boreholes, which is expensive and inconvenient for high altitudes or mountainous terrain. In hydrothermally active areas, the temperature distribution is disturbed by heat convection, resulting in difficulty in obtaining conductive heat flow. In fact, heat can be used as a tracer to quantify groundwater flow. This article presents a method for calculating terrestrial heat flow suitable for hydrothermally active areas, which can correct the influence of groundwater flow to obtain the conductive heat flow reflecting the deep thermal background. The method uses temperature-time series at multiple depths of the shallow crust to calculate the groundwater flow rate. The convective heat flux component is then removed based on information on groundwater movement, and the conductive heat flow can be acquired. The feasibility of the method is verified by a theoretical model. This method has been applied to estimate terrestrial heat flows in northwestern Yunnan, China, which is a hydrothermally active area. The heat flow obtained through our method range from 54.5 to 130.3 mW/m², with an average of 94.5 mW/m², consistent with the high-quality measured heat flow values in the boreholes. This study provides new perspectives for acquiring terrestrial heat flow in areas that are affected by fluid activities.

Heat has been widely used as a groundwater tracer to determine groundwater flow direction and velocity in a way that is ubiquitous, low-cost, environmentally friendly, and easy to use. However, temperature observations are generally short-term and small-scale, meaning they may not be able to reflect long-term changes in the characteristics of groundwater movement. In this study, we utilize 515 days of temperature data, collected from four measurement points in the Kangding area of the eastern Tibetan Plateau, in order to determine the spatial and temporal distribution of groundwater flow velocities using different analytical heat tracing methods. An analysis is conducted to evaluate the impact of thermal parameter uncertainties on the calculation of flow velocity, and a comparison is undertaken between the results of the phase, amplitude, and combined amplitude-phase methods. We subsequently discuss the relationship between flow velocity changes and precipitation. The results show that the estimated flow velocity is more susceptible to the volumetric heat capacity of the saturated sediment than it is to thermal conductivity. The phase method is more suitable for use in calculations in the study area, indicating that precipitation significantly impacts the flow velocity and that this impact is more pronounced in areas with flat terrain compared to areas with significant variation in elevation. Our research provides a comparative study of the heat tracing methods in areas with varied terrains and offers new evidence for the impact of precipitation and topography on groundwater infiltration.

The compositions of chromitites and dunites from Moho transition zone (MTZ) of the Coto block of the Zambales ophiolite, Philippines, are used to investigate the geodynamic transition from anhydrous to hydrous magmatism during subduction initiation (SI). Chromite grains in the chromitites have Cr# values [100 × Cr/(Cr + Al)] and TiO₂ contents ∼35–50 and 0.05–0.30 wt.%, respectively, intermediate between those of chromite in typical MORB‐like lavas (Cr#, ∼20–60; TiO₂, ∼0.6–1.7 wt.%) and boninites (Cr#, ∼70–85; TiO₂, 7Li values varying from ∼−2‰ to +21‰ with most between +10‰ and +15‰, beyond that of normal mantle (+4 ± 2‰) but comparable to those of some arc lavas (up to +12‰). The data set indicates that parental magmas of the high‐Al chromitites originated from hydrated harzburgitic mantle sources and formed temporally between MORB‐like and boninitic magmatism during SI, resulting from the early stage of flux melting in the Zambales proto‐forearc mantle. Modeling of Li diffusion reveals that the MTZ cooled down at a minimum rate of 0.1°C/yr in order to preserve the large δ⁷Li variation of olivine in the dunites, comparable to the thermal conditions below ultra‐slow to slow spreading ridges. Such a stage of transitional magmatism, although displaying notable slab contributions, took place at a sluggish period of slab rollback and asthenospheric upwelling, leading to a trough level of heat flow and magma production during the entire course of SI.

《地球科学》(ISSN 1000-2383;CN42-1874/P) (原刊名《地球科学——中国地质大学学报》ISSN 1000-2383;CN42-1233/P)，创刊于1957年，是由教育部主管、中国地质大学主办的综合性地学学术理论期刊，月刊，2015年改名为《地球科学》,她以反映中国地质大学教学与科研最新的、高水平的基础地质、应用地质、资源与环境地质及地学工程技术研究成果为主要任务。

Satellite thermal infrared remote sensing has received worldwide attention in earthquake-precursors exploration. Meanwhile, it has also encountered great controversy due to the lack of quantitative interpretation of the observations, despite the existing qualitative physical mechanisms being able to greatly help us understand thermal infrared anomalies. Here, we report a potential mechanism to quantitatively analyze co-seismic thermal infrared anomalies based on temperature change caused by stress variation through theoretical, experimental, and field investigations. This paper firstly deduces theoretically the temperature variation during elastic deformation of rock on the basis of the thermodynamic theory. Secondly, three laboratory experiments on rock samples are conducted to verify the theoretical estimates of the temperature changes caused by stress variations using an infrared camera with the spectral range of 8~12 μm. Thirdly, a mechanical model on thrust faults is built to evaluate the co-seismic temperature drop as a result of thrust faulting. The model shows that the co-seismic temperature drop in rocks should be in the order of 0.18 K. This variation in rock temperature may cause a change in heat equivalent to changes in shallow atmospheric temperatures of 3.0–6.0 K, which is in accordance with the temperature anomalies observed by satellite thermal infrared remote sensing. In addition, the temperature change caused by crustal stress variation may involve a large spatial scale, covering the whole focal area, which has characteristics of regional distribution and is conducive to satellite observation. Therefore, a quantitative explanation of the satellite thermal infrared seismic anomaly mechanism can be given via the temperature change caused by crustal stress variation.

Place names that contain rich regional cultural connotations are “living fossils” of history and culture, and they are of great tourist value. Taking the main urban area of Chengdu City as an example, this paper analyzes the cultural characteristics and connotations of place names, as well as their tourist values. This value is believed to mainly include stimulating tourists' interest in traveling, presenting local tourism features, enhancing the travel experience of the visitors and serving the tourism economy. Then this paper discusses the problems of place name cultural heritage and puts forward the tourism development strategies for Chengdu's place name culture. Such strategies could include establishing a tourism place name system of Chengdu scenic spot names, using place names in the restoration and development of ancient scenery, combining place names with food tourism resources and high-quality tourism commodities, developing cultural and creative products related to Chengdu place names, strengthening the theoretical discussion on Chengdu place name culture and conducting dissemination activities for Chengdu place name culture.