...) The closer the perforation was to the lithological interface, the easier it was for hydraulic fractures to propagate through the interface. (2) Direct fracturing of thick coal seams and indirect connection of thin coal seams is advantageous for multi-gas co-production. Shortening the perforation length...

... and empirical models for the prediction and calculation of ground deformation indices for either flat or gently dipping seams under variable topography. However, a few studies are available with respect to the prediction of ground movements under dipping seam conditions. Dipping seam conditions have been...

... ABSTRACT: Sandia National Laboratories and RESPEC personnel designed an experiment to establish a plausible lower bound of the shear strengths of clay seams at the Waste Isolation Pilot Plant (WIPP). Artificial clay seams were prepared from brine mixed with bentonite and applied between salt...

... Abstract: This paper outlines the analysis methods and results used in a geotechnical evaluation performed on the stability of two declines at the Skyline Mine. The Lower O'Connor-A (LOA) seam has been displaced by a fault within the study area at the mine. The declines have been driven...

... Abstract: The physical, structural, and depositional features of the immediate above seam strata which characterize San Juan Mine are localized in extent; regional scale features having little direct influence. Four primary drivers of ground control difficulties associated with the immediate...

... advances, the immediate roof overlying the coal seam, consisting of weak beds, readily cave behind the supports. The main roof lying above the immediate roof consists of strong rock beds and is selfsupporting within a certain roof span. This remains intact and exerts pressure on the barrier pillars...

... strength capacity being exceeded by corresponding state of stress. Several rockburst prevention methods have been developed based on stress control theory, and were applied to Chinese coal mines. Regional stress control methods, such as optimized mine layout, sacrificial protective mining in selected seam...

.... Reservoir Characterization seam subsidence coal cement fly ash grout Upstream Oil & Gas borehole Thickness stabilization project excavation grout hole void shaft mixer truck Tomago Seam investigative grout hole grout pillar Borehole Seam mining geology Australia ARMA 13-597 Some...

... Indian geomining conditions, invariably comprising of multiple seams, some in close proximity, and multiple-pass extractions in thick seams. The method has been recently introduced in India in December 2010 with the operation of ADDCAR Continuous Highwall Mining Machine at Ramagundem Opencast Project-II...

... Abstract: A steeply dipping seam is one with its dip angle in the range of 35° and 55°. Mining of such coal seams is recognized to be difficult in the mining industry. Based on the results of physical simulation experiments and numerical simulation of steeply dipping seam mining...

... Abstract: Bord and pillar is the most common and traditional method of coal extraction in India. This method accounts for over 95% of coal production from underground mines. Multiple seam coal production from in India, accounts for approximately 10% of the underground coal mines. In India...

... recommended at 20% of the explosive charge can reduce the induced seismic force while increasing fragmentation and higher productivity. Upstream Oil & Gas seam productivity limit line enclosure Reservoir Characterization fragmented material size Claystone reduction power plant ground...

... model has the capability to connect the surface subsidence with the seam level strata movements, and to predict the movements and deformations for the strata between them accurately. This paper will apply the subsidence theory in solving two important ground control problems in coal mines: support...

.... metals & mining coal bump seam Reservoir Characterization tailgate area bump operation reservoir geomechanics coal mining method violent failure longwall face data mining mechanism tailgate entry tailgate headgate operator bump incident pillar destress barrier pillar ARMA 11...

... & mining DInSAR topography seam subsidence subsidence trough ARMA 10-417 Case study: measuring subsidence above coal mines using differential interferometric synthetic aperture radar Donovan, J. Department of Mining Engineering, University of Utah, Salt Lake City, UT, USA Ismaya, F. Department...

... ABSTRACT: Compared with gentle dip long-wall fully-mechanized top-coal caving, workface length of top-coal caving for extra-steep-thick seam is short, so increasing section height of sub-level is one of the effective methods that can increase production. Meanwhile there are some challenges...

... for eight US coal seams using in-situ measurements in seven mining districts across the US. These measurements have quantified the higher load carrying capacity of some Utah coal enhanced by high confining stress provided by mostly competent roof and floor rocks and presence of a moderate horizontal stress...

... ability to combine with carbon capture and sequestration (CCS), in which CO2 is separated from the produced syngas and injected into adjacent coal seams for enhanced coalbed methane recovery and CO2 sequestration. This paper presents the primary investigation to the feasibility of the UCG-CCS process...

... Abstract This paper describes the results of numerical analysis on the effect of seam dip on face orientation of Longwall Top Coal Caving method for extraction of inclined thick coal seams. The study was aimed at investigating the differences in caving echanism of the top coal and the above...

..., to develop updated seam-specific strength formulae for South African collieries, using an updated collapsed and uncollapsed pillar data base. In this study attention is focused on bord and pillar primary workings, since this is the only configuration where the pillar load can be simply computed without...