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Compression and hardening over long periods of time, the processes by which coal is formed from plant materials.


the compression, over time, of plant matter into coal


(ˌkoʊ lə fɪˈkeɪ ʃən)

the conversion of plant material into coal by natural processes, as by diagenesis and, in some instances, metamorphism.
References in periodicals archive ?
The organic carbon content of coal increases gradually with increasing coalification degree.
The significance of a thin coal within the open water facies association depends on its origin: given its discontinuous nature and lack of underlying roots, it likely represents organic material (vitrain) resulting from coalification of a transported lycopsid log rather than an in-situ histosol (peat).
6 Pre Coalification Details For The Said Enquiry Is Enclosed.
Changes in the elements' affinity with either the organic or inorganic fraction may also occur during coalification (Christanis et al.
Ibarra JV, Munoz E, Moliner R (1996) FTIR study of the evolution of coal structure during coalification process.
During coalification, peat undergoes several changes as a result of bacterial decay, compaction, heat and time.
Coalbed Methane (CBM) or Natural Gas from Coal (NGC) is technically defined as gas produced naturally by coalification, and found within coal natural gas reservoirs consisting predominately of methane, with smaller amounts of higher hydrocarbons, water vapor, nitrogen, carbon dioxide, or other non-hydrocarbons.
Coal rank indicates the progressive alteration, or coalification, from lignite to anthracite.
Oil shale, also called oil-forming shale, is a kind of combustible organic rock with high ash and low metamorphic grade, which is derived from algae and unicellular lower eukaryote or remains as a result of the processes of putrefaction and coalification.