Controls on the Deposition of Charcoal: Implications for Sedimentary Accumulations of Fusain
Controls on the Deposition of Charcoal: Implications for Sedimentary Accumulations of Fusain
复制标题
对木炭沉积的控制：对 Fusain 沉积物堆积的影响
DOI：
10.1306/d426804a-2b26-11d7-8648000102c1865d
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发表时间：
1995
影响因子：
2
通讯作者：
G. Nichols
中科院分区：
文献类型：
--
作者：
A. Vaughan;G. Nichols
摘要通过一系列实验研究了造波槽中的成波温度、颗粒大小、水矿化度以及悬浮粘土和基质的组成对活性炭在搅拌条件下沉降的影响。木炭的形成温度对木炭浸水的速度有很大影响。在不同温度下形成的炭的微观结构的检查表明，木材内的裂缝的形成影响渗透性，从而影响水渗透的速率。加热至300°C导致细胞壁融合，这抑制了水的渗透并显示出沉降速率。在较高的温度下，细胞壁逐渐破裂，增加渗透性，并且焦炭浸水并沉降。因此，沉积物中木炭的沉降速度和分布受生成木炭的火所达到的温度控制。这种与木炭形成温度有关的分类，对于从沉积存款中的丝炭量确定古野火的大小具有意义。盐度的变化和粘土基质的存在下，也被证明有一个小的影响木炭沉降速率。
ABSTRACT The effects of formation temperature, particle size, water salinity, and composition of suspended clay and substrate on the sedimentation of charcoal under agitated conditions in a wave tank were studied in a series of experiments. The temperature of formation of charcoal has a strong effect on the rate at which charcoal becomes waterlogged. Examination of the microstructure of the chars formed at different temperatures shows that the formation of fractures within the wood affects the permeability and hence the rate of water penetration. Heating up to 300°C results in fusion of the cell walls, which inhibits water penetration and shows the rate of settling. At higher temperatures the cell walls progressively fracture, increasing the permeability, and the chars waterlog and settle aster. The settling rates and hence the distribution of charcoal in sedimentary deposits are therefore controlled by the temperatures reached in the fire that generated the material. This sorting related to temperature of charcoal formation has implications for the determination of the size of a paleowildfire from the volume of fusain in a sedimentary deposit. Salinity variations and the presence of a clay substrate were also shown to have a small effect on charcoal sedimentation rates.