Igneous Intrusions Within The Raton Basin Sierra Grande
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A period of volcanism resulted in igneous intrusions within the Raton Basin-Sierra Grande Uplift Province that was sourced from the upper mantle about 26. 6 billion years ago and is associated with parallel dikes and sills (Higley, 2007). Igneous rocks are common within the Raton Basin and include Tertiary dikes and sills that range in age from 6.7 to 29 5 million years ago (Flores and Bader, 1999). One of the main differences between dikes and sills is that dikes are longer lived magma conduits and sills are features that form when magma is in neutral buoyancy with the surrounding rock (Rooper et al., 2006). These volcanic events are associated with hydrothermal alteration of coal within the basin (Higley, 2007).…show more content… Intrusions within the coal-beds in the northern part of the Raton Basin have been destroyed in vast amounts (Johnson and Finn, 2001). Sills and tabular igneous bodies parallel to bedding are intruded in the middle part of the Raton Formation and are exposed in the Purgatoire River Valley (Watts, 2006). Sills within the basin intrude along a coal-bed instead of through the coal-bed, influencing a larger volume of the coal (Rooper et al., 2006). The sills in the basin are fine grained and distributed across the subsurface as well as intruded into the coals (Pillmore, 2003).
The igneous intrusions in the Raton Basin provide a high temperature and pressure environment promotes an increase in generation of gas (Jian and Cheng, 2014). No evidence suggests that the different intrusions within the coal were at different temperatures (Rooper et al., 2006). It has been suggested that the heat from the dikes enhance adsorption and porosity in coals and also increase the trap capacities of gas storage (Jian and Cheng, 2014). Igneous intrusions create safety problems in the mines underground and the gas created could result in the projection and rapid release of gases (Jian and Cheng, 2014).
Coal-Bed Methane and Natural Gas.
Coal-bed methane is naturally occurring methane with some amounts of hydrocarbon gas as well as non-hydrocarbon gas that is contained in coal seams resulting from chemical