Late Quaternary sea-level change and evolution of Belfast Lough, Northern Ireland: new offshore evidence and implications for sea-level reconstruction
Late Quaternary sea-level change and evolution of Belfast Lough, Northern Ireland: new offshore evidence and implications for sea-level reconstruction
复制标题
北爱尔兰贝尔法斯特湖晚第四纪海平面变化和演化：新的近海证据及其对海平面重建的影响
DOI：
10.1002/jqs.3100
复制
发表时间：
2019
影响因子：
2.3
通讯作者：
Plets R
中科院分区：
文献类型：
--
作者：
Plets R
海平面和地壳均衡因素的相互作用导致复杂的相对海平面（RSL）历史，特别是在副冰环境中。在这种情况下，RSL的过去记录对于理解冰盖历史，地球流变学和由此产生的冰川均衡调整非常重要。开发海平面重建的现场数据通常仅限于浅深度，并且建模的海平面曲线的准确性存在不确定性。我们使用地震地层学，39个振动岩心和26个放射性碳测年，以调查北方爱尔兰的贝尔法斯特湖的冰消历史，并重建过去的RSL。一个典型的序列冰碛，冰川和全新世沉积物被保存。两个海平面低位（均为最大值）-40 m）在c处记录。13.5和11.5k cal abp。每一次之后都是一次快速的海侵和随后的RSL稳定期。第一次海侵与融水脉冲1a的晚期相吻合，RSL稳定发生在c. 13.0和c. 12.2k cal abp（新仙女木）。第二个still/slowstand发生在c之间。10.3和c. 11.5k cal abp.我们的数据提供了限制的方向和时间的RSL变化在冰川消退。闭合深度概念的应用为基于地震地层重建的海平面重建增加了一个误差项。
The interplay of eustatic and isostatic factors causes complex relative sea‐level (RSL) histories, particularly in paraglacial settings. In this context the past record of RSL is important in understanding ice‐sheet history, earth rheology and resulting glacio‐isostatic adjustment. Field data to develop sea‐level reconstructions are often limited to shallow depths and uncertainty exists as to the veracity of modelled sea‐level curves. We use seismic stratigraphy, 39 vibrocores and 26 radiocarbon dates to investigate the deglacial history of Belfast Lough, Northern Ireland, and reconstruct past RSL. A typical sequence of till, glacimarine and Holocene sediments is preserved. Two sea‐level lowstands (both max. −40 m) are recorded at c. 13.5 and 11.5k cal abp. Each is followed by a rapid transgression and subsequent periods of RSL stability. The first transgression coincides temporally with a late stage of Meltwater Pulse 1a and the RSL stability occurred between c. 13.0 and c. 12.2k cal abp(Younger Dryas). The second still/slowstand occurred between c. 10.3 and c. 11.5k cal abp. Our data provide constraints on the direction and timing of RSL change during deglaciation. Application of the Depth of Closure concept adds an error term to sea‐level reconstructions based on seismic stratigraphic reconstructions.