Investigating Palaeoclimate Using Spherules in the Geological Column

地质记录记录了地球上过去的气候条件。岩石中的证据为测试极端气候行为模型提供了唯一可靠的基准。如果没有这一证据，有限的模型就不能可靠地外推到现代数据集之外。在地质记录中，气候指标有多种形式，但大多数是间接测量，需要复杂的模型和外推来为气候模型提供可靠的约束。该项目提出了一种新的、新颖的古环境指示器，它可能会彻底改变我们研究古代过去的方式。隐藏在岩石中的是直径几十到数百微米的微小球体，以前几乎没有人研究过这些球体。其中一些粒子是外星尘埃，在进入大气层的闪光加热过程中与大气保持平衡，并提供了大气气体的直接样本。其中一些是雷击颗粒，记录了极端气候事件的流行情况。另一些是森林大火的产物，由植物中的矿物包裹体和空气中的粉尘融合而成，记录了与气候直接相关的全球自然火灾的发生。一些是起源于火山的火山，记录了火山的全球活动，在前工业时代，火山是气候系统的主要力量。它们与近端的火山沉积不同，分布广泛。最后，少量颗粒也可能是较大的地外物体与地球碰撞的结果，产生影响全球气候的极短周期事件。到目前为止，还没有关于沉积岩中小球体的化学、矿物学和同位素性质的系统研究。然而，我们的团队之前的研究表明，它们是丰富的和可回收的。这项研究的目的是提出这些材料与来源相关的主要标准，为这一新的研究领域提供主要参考。

The geological record holds a record of the past climate conditions on Earth. The evidence in the rocksprovides the only reliable baseline by which models of extreme climate behaviour can be tested. Without thisevidenceclimate models cannot be extrapolated far beyond modern datasets with confidence. There are many forms that climatic indicators take in the geological record, but mostare indirect measures, requiring complex models and extrapolations to provide reliable constraints for climate models. This project proposes a new and novel form of palaeoenvironment indicator that could revolutionise the way we examine the ancient past. Hidden within rocks are tiny spherules, tens to hundreds of microns in diameter, that have been the subject of little study before now. Some of these particles are extraterrestrial dust, which equilibrated with the atmosphere during flash heating during atmospheric entry, and provide a direct samples of atmospheric gas. Some are lightning strike particulates, and record the prevalence of extreme climate events. Others are the products of forest fires, produced by the fusion of mineral inclusions and air-borne dust trapped within plant material and record the global occurrence of natural fires, directly linked to climate.Some are volcanic in originandrecord the global activity of volcanoes, which in pre-industrial epochs were major forcesof the climate system.Unlike proximal volcanic deposits they are widely distributed.Finally, a small number of particles may also be the result of the impact of larger extraterrestrial object with the Earth, generating extreme short-period events effecting global climate. To date there have been no systematic studies of the chemical, mineralogical and isotopic properties of small spherules within sedimentary rocks. Our groups previous research has, however, shown they are abundant and recoverable. The objective of this researchis to produce the primary criteria by which these materials can be related to source, generating the primary reference for this new field of study.