Magnetosusceptability Stratigraphy (MSS): Key to "Floating" Orbitally Forced Timescales, Cyclostratigraphy, and Cyclochronology

磁敏感性地层学 (MSS)：“浮动”轨道受迫时间尺度、旋回地层学和旋回年代学的关键

• 批准号: 9628202
• 负责人: Rex Crick
• 金额: $ 3.5万
• 依托单位: University of Texas at Arlington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-15 至 1997-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9628202&HistoricalAwards=false
• 关键词: Magnetosusceptability; Stratigraphy; MSS; Key; Floating

9628202 Crick Are developing a new method for high-resolution cyclocorrelation and cyclochronology based on a combination of biostratigraphic control and quick, easily performed magnetic measurements. We are calling the method magnetosusceptibility stratigraphy (MSS). The high resolution of Mss is derived from high-frequency events under the control of orbital forcing cycles with current frequencies of the Milankovitch band (19-23, 41, 54, 100, 413 ka). The preliminary data used to document the proposal are from a number of Devonian marine sequences: Morocco, an area chosen because it contains outstanding outcrop exposures, excellent biostratigraphic control, and the Eifelian/Givetian GSSP; Europe, two internationally recognized Devonian sequences in the Montagne Noire, southern France (including the Frasnian/Famennian GSSP); and the Frasnian-Tournaisian of southern Oklahoma. The proposed work will allow use to demonstrate that (1) MSS works, (2) it can provide correlations at better than the best biozone resolution within basins, among basins, and between regions, (3) trends inherent to the MSS curves are evidence of transgressive/regressive or deepening/shallowing sequences, (4) with close sampling MSS proxies for orbital forcing cycles, and (5) once calibrated for the geologic time of interest, the duration of orbital forcing cycles identified from long and reasonably complete stratigraphic sections can be used to establish or construct "floating" orbital forcing timescales. While the recognition that orbital cycles can be traced by the record left in sediments is an important contribution, even more important is the duration of cycles important in the creation of "floating" orbital forcing timescales. These timescales, based on the recognition of the several orbital forcing cycles but not referenced to a curve anchored in the Holocene, will serve to further our understanding of the forces of evolution and sedimentation and to fix the duration of biostratigraphic zones within the l ess precise framework of radiometric time. Such cyclochronologies must eventually lead to a coherent geochronology with increased resolution of at least one order of magnitude over that presently in use.

小行星9628202 正在开发一种新的方法，用于高分辨率的循环相关和循环年代学的基础上结合生物地层控制和快速，易于执行的磁性测量。 我们称这种方法为磁化率地层学（MSS）。 Mss的高分辨率是由Milankovitch波段（19-23，41，54，100，413 ka）的当前频率的轨道强迫周期控制下的高频事件得到的。 用于记录该建议的初步数据来自若干泥盆纪海相层序：摩洛哥，选择该区域是因为它包含突出的露头暴露、极好的生物地层控制和Eifelian/Givetian GSSP;欧洲，法国南部Montagne Noire的两个国际公认的泥盆纪层序（包括Frasnian/Famennian GSSP）;以及俄克拉荷马州南部的Frasnian-Tournaisian。 拟议的工作将允许用于证明：（1）MSS工作，（2）它可以提供比盆地内、盆地间和区域间最佳生物带分辨率更好的相关性，（3）MSS曲线固有的趋势是海进/海退或加深/变浅序列的证据，（4）使用轨道强迫循环的密切采样MSS代理，以及（5）一旦针对感兴趣的地质时期进行了校准，则从长且合理完整的地层剖面中识别的轨道强迫循环的持续时间可用于建立或构造“浮动”轨道强迫时标。 虽然认识到可以通过沉积物中留下的记录来追踪轨道周期是一个重要的贡献，但更重要的是，周期的持续时间对于建立“浮动”轨道作用力时标至关重要。 这些时间尺度，基于几个轨道强迫循环的认识，但不参考固定在全新世的曲线，将有助于我们进一步了解的演变和沉积的力量，并固定在辐射时间的不太精确的框架内的生物地层带的持续时间。 这样的旋回年代学最终必然导致一个连贯的地质年代学，其分辨率至少比目前使用的要高一个数量级。