Landscapes of extinction and evolution: Earth surface processes in the late Palaeozoic

我们需要了解生命在行星表面长期形成过程中的作用，以确定地球在已知的岩石行星中是否是独一无二的，并预测生物圈的未来变化：沉积岩记录是一个有价值的档案，它揭示了地球表面的过程是如何随着生物的进化而进化的，晚古生代的动荡时期是研究这个问题的理想案例。沉积和地貌过程与地球上大多数生命发生在同一个舞台上，物理过程和形式的生物塑造在当今是重要的。不同的生物聚集或分解沉积物;侵蚀、混合、结合或稳定沉积物堆;并能引起湍流，集中或抑制运输沉积物的流体的运动。通过物理-生物反馈，这些过程塑造了我们今天所知的地球，决定了沉积物类型和地貌形态，如沙丘和河道。如果我们要充分理解这些过程的重要性，我们需要在它们首次发挥作用时对地质间隔进行重点调查。晚古生代是研究这些过程如何创造地球景观的完美时期。这一时间间隔晚于陆地景观工程的许多因素的演变（例如，树木，穴居生物），但受到地球系统的重大动荡的影响：赤道干旱化和石炭纪末的热带雨林崩溃，一个主要的冰河时代，以及地球历史上最大的大规模灭绝。古代景观的演变存档在沉积记录中，因为个人的继承主机相和岩性属性，确定过去的环境。这些环境的整体视图，从90 Ma的时间间隔在地球系统中的主要动荡，将展示反馈的景观和沉积，当不同群体的生物体受到压力或全球变化。该项目将重点关注晚石炭世（c。310 Ma）至三叠纪中期（c. 290 Ma）。这段时间见证了物种灭绝和栖息地破坏的主要事件（例如，Kasimovian雨林崩溃; P-T大灭绝）和气候变化（例如，LP冰河时代;欧亚大陆二叠纪沙漠化;卡尼期洪积事件）。该项目将评估景观和沉积如何响应并记录这些系统的转变学生将遵循一系列的工作包，这些工作包以前已被证明是成功地评估与生命进化有关的全球变化（即陆地植物进化对河流形态的影响，以及动物入侵土地的后果）。该项目将从英国和世界各地确定一套合适的案例研究，根据原始现场数据构建详细的沉积地质模型，以确定类似构造和气候环境中的景观，从重大事件前后的间隔。这将与一个主要数据库的建设相结合，该数据库将从晚古生代的划定间隔中确定非海相的长期特征。这种详细的沉积地质实地案例研究的结合方法，以及随时间推移不断变化的沉积特征的地图集，将坚定地解决地球景观如何应对地球前现代历史上最动荡的时期之一。

The role of life in the long-term shaping of the planetary surface needs to be understood to ascertain whether Earth is singular among known rocky planets, and to frame predictions of future changes to the biosphere: the sedimentary rock record is a valuable archive that reveals how Earth surface processes evolved in line with organisms, and the turbulent interval of the late Palaeozoic is an ideal case study to interrogate this question.Sedimentary and geomorphic processes occur in the same theatre as the majority of life on Earth, and biological shaping of physical processes and form is important at the present day. Different organisms aggregate or disaggregate sediment; erode, mix, bind, or stabilize sediment piles; and can induce turbulence in, concentrate, or dampen the movement of fluids that transport sediment. Through physical-biological feedback, these processes shape the Earth as we know it today, determinign sediment type and the morphology of landforms such as dunes and river channels. If we are to fully understand how significant these processes are, we need focussed investigation of geological intervals when they first came into play. The late Palaeozoic is a perfect interval to study how these processes have created the landscapes of planet Earth. The interval post-dates the evolution of many agents of terrestrial landscape engineering (e.g., trees, burrowing organisms), but was affected by major upheavals in the Earth system: equatorial aridification and the collapse of the rainforests at the end of the Carboniferous, a major ice age, and the biggest mass extinction in Earth history.Ancient landscape evolution is archived in the sedimentary record, as individual successions host facies and lithological attributes that identify past environments. A holistic view of these environments, from a 90 Ma interval of major turbulence in the Earth system, will demonstrate the feedback on landscapes and sedimentation that are imparted when different groups of organisms are stressed or advantaged by global changes. The project will focus on the interval of the late Carboniferous (c. 310 Ma) through to the mid Triassic (c. 290 Ma). This interval witnessed major episodes of extinction and habitat destruction (e.g., Kasimovian rainforest collapse; the P-T mass extinction), and climate change (e.g., LP ice age; Permian desertification in Euramerica; the Carnian pluvial episode). The project will evaluate how landscapes and sedimentation responded and recorded these system shiftsThe student will follow a series of work packages that have previously been shown to be successful in assessing global changes related to life evolution (namely, the impact of land plant evolution on fluvial form, and the consequences of the invasion of the land by animals). The project will identify a suite of suitable case studies, from the UK and worldwide, where detailed sedimentary geological models will be constructed from original field data, to ascertain landscapes in similar tectonic and climatic settings, from intervals before and after major events. This will be coupled with the construction of a major database, which will identify secular characteristics of non-marine facies from delineated intervals within the late Palaeozoic. This combined approach of detailed sedimentary geology fieldwork case studies, and an atlas of evolving seidment character through time, will firmly address how the Earth's landscapes responded to what was one of the most turbulent periods of the planet's pre-modern history.