Results 81 to 90 of about 6,606 (218)

Study on Roof‐Control Technology for Gob‐Side Entry Retaining Under Composite Roofs

Energy Science &Engineering, EarlyView.
This study develops a roof‐control technology system for gob‐side entry retaining under composite roofs. By integrating field measurements, theoretical analysis, and numerical simulation, it reveals the spatiotemporal evolution of the plastic zone and proposes a targeted support method, providing theoretical and practical guidance for safe and ...
Dong Li, Yujiang Zhang, Yunlou Du, Haodong Zheng, Baoji Yang   +4 more
wiley   +1 more source

VENDIAN-CAMBRIAN SEDIMENTARY PROVENANCE OF THE UPPER KALAR DEPRESSION (ALDAN SHIELD) ACCORDING TO GEOCHEMICAL DATA

Геодинамика и тектонофизика
There are presented the results of geochemical studies of the Vendian-Cambrian terrigenous rocks in the Upper Kalar depression– sandstones of the Silimkun formation, exposed in the floodplain of the Kilcheris River (left tributary of the China River), in
S. I. Merenkova, I. N. Gromyak, D. N. Dogadkin, E. V. Karpova, R. R. Gabdullin, V. Yu. Vodovozov, T. G. Kuzmina   +6 more
doaj   +1 more source

Optimization of Blasting‑Induced Roof Cutting Parameters in Key Stratum and Its Application in Gob‑Side Entry Retention Technology

Energy Science &Engineering, EarlyView.
This study addresses hard roof coal seam conditions by optimizing key stratum blasting‐cutting parameters through theoretical analysis, numerical simulation, and field tests. It proposes calculation methods for blast hole spacing and delay timing based on stress wave theory, controlling roadway deformation within 35 mm, thereby enhancing resource ...
Qiong Liu, Duanxiang Fu, Hongbin Li
wiley   +1 more source

Numerical Simulation Study on Optimization of Horizontal Sublevel Top‐Coal Caving Mining Technique for Steeply Inclined Extra‐Thick Coal Seam

Energy Science &Engineering, EarlyView.
As the sublevel height increases, the top‐coal recovery amount gradually increases, but both the top‐coal recovery rate and the thickened top‐coal recovery rate show a downward trend, and the decline in the top‐coal recovery rate is gradually increasing. The comparison indicates that the optimal sublevel height is 20 m.
Hongsheng Tu, Dingyi Hao, Wenhong Xiao, Fuhao Jiang, Shikun Xu   +4 more
wiley   +1 more source

Damage Characteristics and Stress Distribution Law of Overburden Rock in Multiple Mining of Close Coal Seams

Energy Science &Engineering, EarlyView.
This study on close coal seams shows that multi‐seam mining increases the height of the fractured zone from approximately 26 m (single upper‐seam mining) to about 49 m. When the lower seam is mined after the extraction of the upper seam, the heights of both the caved zone and the fractured zone increase by approximately two times.
Xiaoyu Wu, Lei Guo, Zedong Sun, Xiaowei Wu, Nan Zhang   +4 more
wiley   +1 more source

Study on Fluid Pressure in Tubing, Dynamic Stress in Reservoir, and Fracture Propagation Morphology During Variable‐Rate Hydraulic Fracturing

Energy Science &Engineering, EarlyView.
Variable‐rate hydraulic fracturing can induce unsteady flow in the tubing, thereby generating fluctuating fluid pressure near the bottom‐hole reservoir. Dynamic stress is generated in the reservoir under the action of fluctuating fluid pressure and propagates as stress waves.
Zhu Ge, Wang Chaojing, Li Weicheng
wiley   +1 more source

Fracture Development Mechanism of Water‐Isolating Soil Layers During Downward Mining of Shallow‐Buried Coal Seam Groups

Energy Science &Engineering, EarlyView.
This study systematically investigates the fracture development mechanisms of water‐isolating soil layers under the coupled effects of repeated mining and groundwater seepage during the downward mining of shallow‐buried coal seams. The findings provide a theoretical basis for evaluating stratum stability and preventing roof water inrush.
Tao Yang, Shuqi Zhang, Jie Zhang, Haifei Lin, Dong Liu, Hui Liu, Yiming Zhang, Jianping Sun   +7 more
wiley   +1 more source

Post‐Stimulation Hydraulic Response and Productivity Constraints of a Low‐Productivity Carbonate Geothermal Well in the Small Intramontane Basin, Beijing Piedmont, North China

Energy Science &Engineering, EarlyView.
Formed ~1.4 Ga, the carbonate reservoir of the Jixian System is a key geothermal reservoir in northern China. Differential basin–mountain evolution since the Cenozoic led to distinct reservoir‐forming histories; consequently, this same reservoir shows marked productivity contrasts between intramontane basins and the large rift Bohai Bay Basin ...
Chuanqing Zhu, Kefu Li, Wansen Yao, Wanqing Geng, Yonghui Huang, Shu Jiang, Nansheng Qiu   +6 more
wiley   +1 more source

RELATIONSHIP BETWEEN PETROGRAPHIC PORE TYPES AND CORE MEASUREMENTS IN SANDSTONES OF THE MONSERRATE FORMATION, UPPER MAGDALENA VALLEY, COLOMBIA

CT&F Ciencia, Tecnología & Futuro, 1997
Patterns of porosity in sandstones of the Monserrate Formation (Upper Magdalena Valley) exposed in polished blocks have been digitally recorded using an image processor coupled to a scanning electron microscope operated in backscatter electron mode ...
R EHRLICH, G COBALEDA, J BARCLAY FERM
doaj  

Notable Impact of Paleotectonic Stress on Gold Mineralisation in the West Qinling Orogen

Geological Journal, EarlyView.
By applying fuzzy clustering and multiple inverse methods, we systematically processed the data of vein and fault slip in this ore deposit to reveal the transition of orogenic geological environment and paleotectonic stress field. Our research results show two different stress states: the northwest–southeast extensional stress field and the northeast ...
Hongyan Wang, Aibing Chen, Jian Yang, Yuan Zhang   +3 more
wiley   +1 more source