まとめ
炭酸炭丸には2種類の炭素が含まれ,炭素13と炭素12の比率によって異なります. これは,沼地の沈殿物と化石由来の炭酸材料の混合物を示唆しています.
科学分野:
- 地質化学 地質化学
- パレオボタニーは古植物学です.
- 堆積物学 堆積物学 堆積物学 堆積物学 堆積物学
背景:
- 炭丸は,鉱化によって保存された化石化した植物物質であり,通常はカルサイトまたはピライトです.
- 炭丸の炭酸塩の起源を理解することは,その形成環境の解釈に極めて重要です.
研究 の 目的:
- 炭酸塩の炭素同位体組成 (C(13):C(12) を異なる種類の炭丸で調べる.
- 炭丸がオウチゲンとオロゲン炭酸の混合物を含んでいるという仮説を検証するために.
主な方法:
- 炭素同位体比 (C(13):C(12)) を"普通""野生"および"混合"炭丸から得られた炭酸で分析.
- 異なる炭酸塩源を特定するために,同位体シグネチャの比較.
主要な成果:
- 研究された炭丸のC13:C12比は,炭酸塩の混合物と一致していた.
- 1つの成分は,Cの減少を示した ((13),これは,in-situの沈殿された炭酸塩の特徴である.
- 別の成分はC ((13) で濃縮されており,外来化石の断片と一致しています.
結論:
- 石灰炭丸は,異なる割合の沈殿炭酸と外部のデトリタル物質で構成されています.
- 同位体データは,早期のダイアゲネティック降水と,石炭沼環境内の化石断片の組み込みの両方を含むモデルをサポートします.
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