...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Sedimentology: Journal of the International Association of Sedimentologists >Controls on accumulation of anomalously thick coals: Implications for sequence stratigraphic analysis
【24h】

Controls on accumulation of anomalously thick coals: Implications for sequence stratigraphic analysis

机译：对异常厚煤的积累的控制：序列地层分析的影响

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Coal seams preserve high-resolution records of ancient terrestrial water table (base level) fluctuations in ancient peat accumulations, but little is known about base level change in anomalously thick coal seams. Using the Early Cretaceous 91 m anomalously thick No. 6 coal (lignite) seam in the Erlian Basin (north-east China) as a case study, the origin and evolution of peat accumulation in a continental faulted basin is revealed by sedimentological, sequence stratigraphic and coal petrological analyses. The lignite is dominated by huminite, indicating oxygen-deficient and waterlogged conditions in the precursor mire. Four types of key sequence stratigraphic surfaces are recognized, including paludification, terrestrialization, accommodation-reversal and give-up transgressive surfaces. Vertically, the No. 6 coal seam consists of fourteen superimposed wetting-up and drying-up cycles separated by key sequence stratigraphic surfaces, with each of these cycles having a mean duration of about 156 to 173 kyr. In a high accommodation peat swamp system, the wetting-up cycles are generally characterized by an upward increase in mineral matter and inertodetrinite and an upward decrease in huminite with the paludification surface as their base and the give-up transgressive surface or accommodation-reversal surface as their top, representing a trend of upward-increasing accommodation. In contrast, the drying-up cycles are generally characterized by an upward decrease in mineral matter and inertodetrinite and an upward increase in huminite, with the terrestrialization surface as their base and the accommodation-reversal surface as their top, representing a trend of upward-decreasing accommodation. A multi-phase mire stacking model for accumulation of the coal seam is proposed based on high-frequency accommodation cycles and the stratigraphic relationships between coal and clastic sediments. High-frequency accommodation cycles in the coal are closely related to water table fluctuations in the precursor mires and are driven by high-frequency climate via changes in the intensity and seasonality of precipitation in a relatively stable subsidence regime. Recognition that the No. 6 coal seam is composed of multiple stacked mires has implications for studies addressing palaeoclimatic inferences and genesis of anomalously thick coals seams.
机译：煤层保持古代泥炭蓄积中古代水位的高分辨率记录（基础水平）波动，但对大致厚煤层的基础水平变化很少。使用早期的白垩纪91米异常厚的6号煤（褐煤）煤层（华东地区）作为案例研究，泥炭堆积在陆地故障盆地中的起源和演变是由沉积学，序列地层展开的和煤炭思科分析。褐煤以湿润为主，表明前体摩擦中的缺氧和涝脂条件。识别出四种类型的关键序列地层表面，包括繁荣，陆地化，住宿 - 逆转和放弃越野侵入表面。垂直地，6号煤层由14个叠加的湿润和干燥循环组成，由关键序列地层表面分开，每个循环中的每一个具有约156至173kyr的平均持续时间。在高容纳泥炭沼泽系统中，润湿循环通常具有矿物质和惰性四虫石的向上增加，湿润的向上减少与悬挂表面为它们的基础，并且放大海洋表面或容纳逆转表面作为他们的顶部，代表着越来越多的住宿趋势。相反，干燥循环通常具有矿物质和惰性四虫石的向上减少，幽默的向上增加，具有陆地化表面作为它们的基础和逆转表面作为其顶部，代表向上的趋势 - 降低住宿。基于高频容纳循环和煤和碎屑沉积物之间的地层关系，提出了一种用于煤层积累的多相摩擦堆叠模型。煤中的高频住宿循环与前体摩尔的水表波动密切相关，并且通过在相对稳定的沉降状态下通过降水的强度和季节性的变化来驱动高频气候。认识到第6号煤层由多个堆叠的泥土组成，对寻址古跨越煤煤层的古生物推论和成因的研究有影响。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号