Heilongjiang Earthquake Agency

Tamusu, the only identified super-large sandstone-hosted uranium deposit in the Bayingobi Basin, provides an important natural laboratory for evaluating ore-controlling factors and genetic models of sandstone-type uranium mineralization. Based on core descriptions from more than 200 boreholes, log facies analysis and geochemical environmental proxies, this study constrains the sedimentary–mineralization architecture and key controlling factors of the deposit. Uranium orebodies are mainly hosted in the upper member of the Lower Cretaceous Bayingobi Formation (Sq2) within a gravity flow-dominated fan-delta–lacustrine system. Braided distributary channel sands on the fan-delta plain and subaqueous distributary channel sands on the delta front constitute the principal uranium reservoirs, controlling both the migration pathways and storage space for U-bearing fluids. Mineralization is jointly governed by fan-delta architecture, interlayer oxidation zonation and reducing agents. The interlayer oxidation zone displays a north-thick–south-thin geometry, and uranium orebodies are concentrated at redox transition positions, with grades of 0.01–0.33 wt%. The metallogenic evolution can be summarized in three stages: syndepositional uranium pre-enrichment, interlayer oxidation mineralization, and a late hydrothermal/diagenetic overprint that mainly modified reservoir properties, favored ore preservation, and did not contribute to the primary uranium budget. Accordingly, a genetic model of “fan-delta architecture + interlayer oxidation control + late overprint and preservation” is proposed to guide exploration in the Bayingobi Basin and analogous sandstone-type uranium systems.

2-phenylethanol (2-PE) is a high-value aromatic alcohol. Its bioproduction is limited by pathway bottlenecks, limited by a rate-limiting decarboxylation step, product toxicity, and volatilization. We sought to build an efficient Escherichia coli (E. coli) platform by optimizing the segment of the Ehrlich route that converts L-phenylalanine (L-Phe) to 2-PE, together with a food-grade soybean-oil overlay for in situ product recovery (ISPR). Whole-cell assays showed that phenylpyruvate decarboxylation was the main bottleneck when the yeast decarboxylase Aro10 was used. A phylogeny-guided screen identified Lactococcus lactis KivD as a superior substitute in E. coli. After replacing Aro10 with KivD and tuning expression, leveraging endogenous glutamate dehydrogenase (GDH) for NAD(P)H recycling enabled sufficient cofactor regeneration, yielding 49.5 mM 2-PE from 50 mM L-Phe with 99.0% conversion. At the shake-flask scale, a fed-batch L-Phe feeding strategy coupled with a 2:1 soybean-oil overlay for in situ product removal reduced toxicity and volatilization losses, producing 130 mM 2-PE (15.9 g/L). Using soybean oil as an ISPR phase effectively sequestered 2-PE from the aqueous phase, minimizing volatilization and increasing the overall recovered yield to 94.2% based on L-Phe consumption. Replacing the rate-limiting decarboxylation step with KivD, balancing redox through cofactor recycling, and coupling the pathway to a mild oil-overlay recovery increased flux and enabled high-titer 2-PE in E. coli. The workflow of bottleneck substitution plus biocompatible in situ recovery can be transferred to related aromatic alcohols and provides a foundation for de novo routes and high-cell-density fermentations that target still higher titers.

Abstract The Changbaishan volcanic field, which includes the Tianchi and Wangtian'e volcanoes in China and the Namphothe volcano in North Korea, is one of the most complex and hazardous volcanic regions on Earth due to its tectonic setting and explosive Holocene activity. Although the magmatic structure beneath the Tianchi volcano has been widely studied, the subsurface systems beneath the Wangtian'e and Namphothe volcanoes remain unknown. Using receiver function data from a dense seismic array, we present the first high‐resolution images of crustal thickness and V p / V s structure across the Tianchi and Wangtian'e volcanic fields. stacking shows that the Tianchi volcano is underlain by a thick crust with high V p / V s , while the Wangtian'e volcano has normal crustal thickness but similarly elevated V p / V s . Common Conversion Point imaging reveals strong negative phases at depths of 5–10 km beneath both volcanoes, marking the likely tops of major crustal magma chambers. Ambient noise tomography, derived from the densest broadband data set collected in this region, also detects pronounced low‐velocity zones at similar depths. These results indicate that the two volcanoes form an interconnected magmatic system: mantle‐derived melts pool near the Moho beneath the Tianchi volcano and then migrate laterally to supply separate magma reservoirs beneath the Tianchi and Wangtian'e volcanoes. Notably, we identify partial melt beneath the Wangtian'e, a volcano long regarded as dormant or extinct, underscoring the need for continued monitoring and further geophysical studies of the entire Changbaishan volcanic complex.

According to historical records, a strong earthquake with magnitude 7 occurred in Lingqiu, Shanxi, in 1626 with an epicenter at 39.4°N, 114.2°E. The epicenter location and magnitude have been primarily determined through historical earthquake disaster records. However, owing to the loss and omissions of historical earthquake disaster records, certain deviations in the epicenter location and magnitude may exist. From field observations, landslides were found to be highly developed near the epicenter of this earthquake. Therefore, this study collected historical materials on the related damage and determined the effective range of earthquake-induced landslides. Inter-pretation of landslide bodies near the epicenter was performed using high-resolution remote-sensing images, they were confirmed on site, and a landslide database was established. The macroscopic epicenter was determined to be at 39°25′42″N and 114°12′10″E, located 0.30 km east and 3.0 km north of the original epicenter. The landslides from the Lingqiu earthquake were roughly distributed in two directions, northeast and northwest of the epicenter. The actual distribution of the landslide mass had a length of 75 km on the outer envelope, and the magnitude of the Lingqiu earthquake has been revised to magnitude 7.1. This method can be applied to correct historical strong earthquake event parameters worldwide.

Abstract Quantifying fault frictional properties is fundamental to understanding slip behavior and seismic hazard. We analyze 2 years of Sentinel‐1 SAR data following the 2023 Turkey earthquake doublet using Independent Component Analysis‐enhanced Small Baseline Subset‐InSAR, to resolve postseismic deformation and invert for afterslip on the East Anatolian and Çardak faults. Within a rate‐and‐state framework, we estimate the friction parameter in postseismically stable regions ( R 2 > 0.9), showing that afterslip dominantly occurs in high velocity‐strengthening regions, whereas coseismic rupture and aftershocks cluster near low zones or adjacent unstable patches. Depth‐dependent slip partitioning indicates a brittle–ductile transition modulated by frictional heterogeneity, and eastward migration of deep afterslip and segmentation of slip behavior highlight postseismic deformation complexity. Elevated values on the Pütürge segment indicate rupture propagation was limited by velocity‐strengthening regions. These results suggest that frictional heterogeneity likely governs slip partitioning and provide quantitative constraints for seismic hazard assessment in continental fault systems.

The North China Plain is one of the largest plains in China, where domestic water supply, agricultural irrigation, and industrial production rely on groundwater resources. Groundwater quality is increasingly affected by the combined effects of intense human activity and geological conditions. To ensure sustainable groundwater utilization, it is crucial to investigate the hydrogeochemical processes linked to hydrogeological conditions. In this study, 85 samples were collected from cold wells and 56 samples from geothermal wells in North China. By integrating self-organizing mapping (SOM), hydrochemical and isotopic analysis, nitrate distribution, water quality index (WQI), and human health risk assessment (HHRA) methodologies, we systematically evaluated the spatial variability of groundwater quality and the associated health risks in the region. Hydrochemical analysis indicates that groundwater recharge is primarily driven by atmospheric precipitation. Shallow cold groundwater in Cluster 1 exhibited a mixed phase, whereas geothermal water in Clusters 2 and 3 and cold groundwater in Cluster 4 predominantly displayed a Na-Cl type. Cation exchange processes are the primary factors controlling ion composition. Water quality assessment studies indicate that 75.15% of the groundwater is suitable for drinking. The average water quality index of the geothermal water was higher than that of the cold water. Shallow groundwater in plains is significantly affected by agricultural activities, typically manifested as elevated NO3− concentrations. Arsenic and boron are the primary non-carcinogenic risk pollutants in geothermal water, and children are more vulnerable than adults. The non-carcinogenic risk zones for cold wells were primarily distributed in Shijiazhuang, Baoding, and the coastal areas downstream of the Yellow River. Tianjin has high-risk geothermal water. Therefore, effective strategies must be implemented to protect this valuable water resource and achieve sustainable development in the region.