Composition, Origin, and Accumulation Model of Coalbed Methane in the Panxie Coal Mining Area, Anhui Province, China.

To investigate the geochemical characteristic, genetic types, and accumulation model of coalbed methane (CBM), 16 samples from a burial depth of 621-1494 m were collected in the Panxie Coal Mining Area of Huainan Coalfield. The results indicate that the samples are dominated by methane, and the concentrations are distributed in the range of 73.11-95.

Effective Approach with Extra Desorption Time to Estimate the Gas Content of Deep-Buried Coalbed Methane Reservoirs: A Case Study from the Panji Deep Area in Huainan Coalfield, China.

In this study, 11 core coal samples were collected from deep-buried coalbed methane (CBM) reservoirs with burial depth intervals of 900-1500 m for gas estimation content by a direct method. In desorption experiments, the cumulative gas desorption data were recorded within 2 h in the field on the basis of the China National Standard method. For accuracy, two improved methods were proposed.

Methodology for Lost Gas Determination from Exploratory Coal Cores and Comparative Evaluation of the Accuracy of the Direct Method.

In the coal exploration of China, the commonly used direct method within 120 min has potential errors in lost gas calculation of deep coal seam for its complex geological conditions. The exploration of deep coal resources by drilling holes in Huainan of Eastern China offered an opportunity to starting research into developing a new method. A developed method with error analysis was constructed to estimate the lost gas using the total desorption process obtained from exploratory coal cores.

Preliminary Assessment of the Resource and Exploitation Potential of Lower Permian Marine-Continent Transitional Facies Shale Gas in the Huainan Basin, Eastern China, Based on a Comprehensive Understanding of Geological Conditions.

The Huainan Basin in eastern China contains abundant shale gas resources; the Lower Permian is an exploration horizon with a high potential for shale gas in marine-continent transitional facies. However, few detailed analyses have investigated shale gas in this area. In this paper, a comprehensive investigation of the geochemical characteristics, physical properties, and gas-bearing capacities of shale reservoirs was conducted, and the resource and exploitation potential were evaluated.

Ground surface settlement analysis of shield tunneling under spatial variability of multiple geotechnical parameters.

This paper presents an efficient method of shield tunneling reliability analysis using spatial random fields. We introduced two stochastic methods into numerical simulation. The first one computes the maximal ground surface settlement using classical statistics, in which the response surface method is utilized to calculate the failure probability by first-order second moment.