Sedimentary Rocks and Mining Mineral Exploration

Question: Describe about the Sedimentary Rocks and Mining for Mineral Exploration. Answer: Introduction Mineral exploration and mining is the process of exploration and extraction of valuable geological materials from underground and excavation sites. The mining task comprises of exploration to determine the site of mineral using research and other technical methods, followed by a feasibility study of the mining activity. Depending on the outcome of the feasibility study, the activity of mining is taken up.The task of mining comprises of excavation of layers of earth depending on the type of mining that is carried out. Surface and sub-surface (underground) are the two broad categories of mining. Surface mining is the name given to the mining task that includes the process of removing the surface or layers of earth to reach the mines. The process includes open-pit mining, quarrying, strip-mining, mountaintop removal and landfill mining. Sub-surface mining or underground mining is the process of extracting minerals from the deposits through tunnels and shafts without disrupting the surro unding areas. Slope mining, shaft mining and drift mining are a few examples of sub-surface mining (Brady and Brown 2013). Mining in any from requires excavation of earth and involves the profiling the geology of the mining area. An understanding of the nature of the site provides an insight into the technique that can be used for the excavation process. The rationale behind the difference in techniques is the properties and characteristics of the material the site is formed of. Thus, the property of rocks has an influential status in mining engineering. Rock mechanics is concerned with the study of the properties of rock and the response of rocks to mechanical activities. Rock mechanics is extensively used in the mining industry to understand and exploit the properties of rocks in the process of mining. Sedimentary rocks Sedimentary rocks are formed by the lithification of sediments deposited over time. The formation of sedimentary rocks begins with the process of weathering and erosion of existing rocks in the nearby regions. A number of natural factors that include air and water carry the broken and loosened up materials. These carriers carry the sediments from the source to the destination locations and deposit the sediments. Gradually the sediments are affected by surrounding moisture and the minerals in the sediments starts settling down and consolidate in a process known as cementation. The carriers deposit more sediment over the cemented sediments forming lithostatic pressure, which solidifies the former sediments in a process termed as compaction. Sedimentary rocks are broadly classified in to four groups: clastic, chemical, bio-chemical and others (Obert and Duvall 2013). The typical weathering of bigger rocks forms clastic rocks. The rocks are weathered over time into smaller rocks and the pressure of fresh sediments consolidates these weathered rocks. Depending on grain size, clastic rocks can be further classified into conglomerates, sandstone and mudstone. Chemical rocks are formed by the precipitation of minerals on the bottom of water bodies. Bio-chemical rocks are formed as a result of biological processes. Limestone and fossil fuel are the classic examples of bio-chemical rocks. Other types of sedimentary rocks are formed due unprecedented, irregular events such as floods or mining (Sivakugan et al. 2013). Gypsum mine tragedy A case study According to a report by BBC (BBC News 2016), a gypsum mine in Pingyi Countrys Linyi city in the Shandong province in China a gypsum mine collapsed in the late 2015. The incident led to the entrapment of around 17 miners in the tragedy. The basic reason for such collapses is the lack of analysis of the material the mine is composed of. The design of the support structure of the mine also plays a crucial role. Sedimentary rocks are ductile by nature and distorts under pressure. The underground mining of sedimentary rocks requires support structure to support the mine walls on the excavation of the minerals. The construction of the support structure demands the understanding of sedimentary rocks and the properties of the mineral being extracted (Spiezia et al. 2016). The gypsum mine in Shandong province was unable to construct an appropriate support structure and also failed to provide an escape route which a mine of sedimentary rock requires. Conclusion Mining involves considerable costs and efforts. Analysis of the properties of the minerals and the effect it exerts on its surrounding land structure is an essential requirement in the process of mining. Rock mechanics is the study of mechanical behavior of rocks and applying methods to exploit the analyzed properties. The subject is of considerable importance to the mining industry as it provides the foundation based on which the organization initiates the activity. Mining engineering is another subject that has considerable role to play in the mining industry. Knowledgeable decisions and trained manpower is the key to overcome the issues. References BBC News. (2016). Chinese mine owner kills himself as 17 miners remain trapped - BBC News. [online] Available at: https://www.bbc.com/news/world-asia-china-35185133 [Accessed 22 Nov. 2016]. Brady, B.H. and Brown, E.T., 2013.Rock mechanics: for underground mining. Springer Science Business Media. Feng, R.M. and Chugh, Y.P., 2014. Development of backfill design parameters for control of surface and subsurface mining related movements.Legislation, Technology and Practice of Mine Land Reclamation,1, p.297. Obert, L. and Duvall, W.I., 2013. Rock Mechanics and the Design of Structures in Rock. Sivakugan, N., Shukla, S.K. and Das, B.M., 2013.Rock Mechanics: an introduction. Crc Press. Spiezia, N., Salomoni, V.A. and Majorana, C.E., 2016. Plasticity and strain localization around a horizontal wellbore drilled through a porous rock formation.International Journal of Plasticity,78, pp.114-144.