Diagenesis - Diagenesis

Japanese: 続成作用 - ぞくせいさよう（英語表記）diagenesis

It is the accumulation of processes that affected sediments after they were accumulated. However, some geologists use the term to refer exclusively to processes that occurred before lithification. Gümbel included changes due to metamorphism in the term [Gümbel: 1868], while Walther limited it to processes that occurred before metamorphism, and this is the term that is commonly used [Walther: 1894, Larsen & Chilingar: 1967]. It may also be used to refer to the recrystallization of rocks that occurs under conditions close to those on the Earth's surface [Mason: 1978]. In general, it is used to refer to the phenomenon in which sediments change into solidified sedimentary rocks through chemical and physical changes during and after deposition, including processes such as the reduction of interparticle voids due to compaction caused by superimposed loads, cementation that bonds particles together by depositing substances into interparticle voids, and metasomatism in which the chemical composition changes due to circulating water. Diagenesis is a phenomenon that occurs near the earth's surface and is broadly considered to be part of metamorphism; the two are essentially continuous, but diagenesis, which occurs at conditions close to room temperature, and metamorphism, which occurs under high temperature and pressure, are usually treated separately [Katayama et al.: 1970]. On the other hand, weathering is a process in which rocks slowly break down and change, so weathering is not usually included in diagenesis. The Greek words dia and genesis mean origin.

Source: Asakura Publishing Dictionary of Petrology Information

Japanese:

堆積物が溜まった後に影響を与えた作用を集積したもの．しかし地質学者によってはこの過程は石化作用が起こる以前のものに限定して用いている．ギュンベルはこの語に変成作用による変化を含めたが［Gümbel : 1868］，ウォルターは変成作用の起こる以前の過程に限定し，これが一般に使われている［Walther : 1894, Larsen & Chilingar : 1967］．地表に近い条件で起こる岩石の再結晶作用に用いる場合がある［Mason : 1978］．一般には堆積物が堆積中および堆積後に，化学的,物理的変化によって固結した堆積岩に変わる現象に用い，積載荷重で生じた圧密による粒子間隙の減少，粒子間隙への物質の沈着など粒子相互を結合する膠結作用，循環水によって化学組成が変化する交代作用などの諸作用が含まれる．続成作用は地表近くで起こる現象で，広い意味では変成作用の一部に含まれ，両者は本質的には連続しているが,通常は常温に近い条件で起こる続成作用と，高温高圧の下で起こる変成作用は区別して扱われる［片山ほか : 1970］．一方，風化作用は岩石がゆるく分解し変化する過程なので，普通は続成作用に風化作用は含まれない．ギリシャ語のdiaは通して，genesisは起源の意味．

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