In the light of analysis of the internal relations among the source strata for magmatism, thegranitic magmas and the endogenic metallizations, the basic regularity of petrogenesis and metallo-genesis of Nanling crust-...In the light of analysis of the internal relations among the source strata for magmatism, thegranitic magmas and the endogenic metallizations, the basic regularity of petrogenesis and metallo-genesis of Nanling crust-derived type granitoids can be generalized as follows: (1) Two suites ofsource strata for Magmatism-the Pre-Sinian and the Lower Sinianl here the unity of the old foldbasement, the source strata for magmatism and the source strata for metallization are particularlyhighlighted. (2) Multi-stage melting of source strata for magmatism resulting in the formation ofmajor ore-related granites of three different stages (the Late Jinningean stage, the Late Caledonianstage, and the Late Indosinian-Late Yanshanian stage) under the control of tw0 tectonic units(geosyncline and diwa). (3) Three endogenic meta1logenic epoches accompanying the three stagesof ore-related granitic magmatism. (4) One major metallogenic epoch characterized by concentrat-ed commercial metallizations in large scale related to the Yanshanian crust-derived type granites.Tectonically,this major metallogenic epoch is exactly consistent with the stage of violent diwa ac-tivity. This is by no means fortuitous, but is the unavoidable result of the development and evolu-tion of the objective geologic history.展开更多
The stability of inclined shaft lining structure (ISLS) in complex water-rich strata is affected by many factors, suchas water pressure, joint, soft rock, lining corrosion and so on. The instability of the ISLS will a...The stability of inclined shaft lining structure (ISLS) in complex water-rich strata is affected by many factors, suchas water pressure, joint, soft rock, lining corrosion and so on. The instability of the ISLS will affect the safe andefficient coal mine production. Bathe sed on the geological conditions of the Xiaobaodang coal mine, this papertested the evolution characteristics of concrete composition in long-term water seepage areas and revealed theinfluence mechanism of corrosion weakening of shaft lining (SL) in water-rich strata. Meanwhile, transientelectromagnetic, ground penetrating radar, and infrared monitoring are used to detect the water-rich zones, anddamage zones of surrounding rock and lining water seepage zones, and a three-level safety evaluation model forthe instability risk of ISLS is constructed. Water abundance of the surrounding rock, surrounding rock deterioration, and shaft lining seepage were the specific indicators in the model. The main inclined shaft (MIS) in thestudied coal mine is divided into three levels: non instability risk zone, potential instability risk zone, and highinstability risk zone. According to the evaluation results, comprehensive prevention and control measures of“hydrophobic hole drainage” and “back-lining grouting” are adopted for the water inrush source and the surrounding rock micro-crack water channel. The precise prevention and control of ISLS is realized. The researchresults also provide a reference for the stability evaluation of ISLS and the accurate prevention and control undersimilar conditions.展开更多
文摘In the light of analysis of the internal relations among the source strata for magmatism, thegranitic magmas and the endogenic metallizations, the basic regularity of petrogenesis and metallo-genesis of Nanling crust-derived type granitoids can be generalized as follows: (1) Two suites ofsource strata for Magmatism-the Pre-Sinian and the Lower Sinianl here the unity of the old foldbasement, the source strata for magmatism and the source strata for metallization are particularlyhighlighted. (2) Multi-stage melting of source strata for magmatism resulting in the formation ofmajor ore-related granites of three different stages (the Late Jinningean stage, the Late Caledonianstage, and the Late Indosinian-Late Yanshanian stage) under the control of tw0 tectonic units(geosyncline and diwa). (3) Three endogenic meta1logenic epoches accompanying the three stagesof ore-related granitic magmatism. (4) One major metallogenic epoch characterized by concentrat-ed commercial metallizations in large scale related to the Yanshanian crust-derived type granites.Tectonically,this major metallogenic epoch is exactly consistent with the stage of violent diwa ac-tivity. This is by no means fortuitous, but is the unavoidable result of the development and evolu-tion of the objective geologic history.
基金Financial support for this work was provided by the National Natural Science Foundation of China(52104155)Natural Science Foundation of Beijing(8212032)+2 种基金the Postdoctoral Research Foundation of China(2023M733778)an Open Research Grant of Joint National-Local Engineering Research Centre for Safe and Precise Coal Mining(EC2022012)the Fundamental Research Funds for the Central Universities(2023ZKPYNY03).
文摘The stability of inclined shaft lining structure (ISLS) in complex water-rich strata is affected by many factors, suchas water pressure, joint, soft rock, lining corrosion and so on. The instability of the ISLS will affect the safe andefficient coal mine production. Bathe sed on the geological conditions of the Xiaobaodang coal mine, this papertested the evolution characteristics of concrete composition in long-term water seepage areas and revealed theinfluence mechanism of corrosion weakening of shaft lining (SL) in water-rich strata. Meanwhile, transientelectromagnetic, ground penetrating radar, and infrared monitoring are used to detect the water-rich zones, anddamage zones of surrounding rock and lining water seepage zones, and a three-level safety evaluation model forthe instability risk of ISLS is constructed. Water abundance of the surrounding rock, surrounding rock deterioration, and shaft lining seepage were the specific indicators in the model. The main inclined shaft (MIS) in thestudied coal mine is divided into three levels: non instability risk zone, potential instability risk zone, and highinstability risk zone. According to the evaluation results, comprehensive prevention and control measures of“hydrophobic hole drainage” and “back-lining grouting” are adopted for the water inrush source and the surrounding rock micro-crack water channel. The precise prevention and control of ISLS is realized. The researchresults also provide a reference for the stability evaluation of ISLS and the accurate prevention and control undersimilar conditions.