The Earth?s surface crust is host to (1) our mineral, hydrocarbon and water resources, (2) a full-spectrum record of past climate change, (3) a natural laboratory of the magnitude and rates of change in ecosystems under the range of past conditions, (4) the archive of the evolutionary history of life, including biodiversity and evolutionary innovation throughout Earth?s history, particularly during times of rapidly changing environmental conditions, and (5) a record of the processes that lead to or respond to natural hazards such as earthquakes, flooding, volcanic eruptions. Scientific investigation into these and related issues is primarily the purview of sedimentary geologists and geochemists and paleontologists - increasingly working in collaboration. Recent scientific efforts in sedimentary geology and paleobiology (SGP) have led to notable advances in radiometric calibration of the geologic record and in our interpretive understanding of deep-time earth processes that cannot be inferred from any other archive than the Earth?s crustal carapace. Despite these advances the SGP community has not convened in the past decade or more to discuss and develop a SGP-wide and coherent vision for the future of research in our broader disciplinary field. Furthermore, funding levels to support SGP research are increasingly inadequate limiting the pursuit of exciting new scientific opportunities and directions as well as the development of intellectual, cultural and technical infrastructure needed to support research and mentoring activities. PIs propose a workshop for the exchange of ideas among representatives of the various sub-disciplines in SGP in order to identify key research questions and topics in sedimentary geology and geochemistry, deep-time paleoclimatology, and paleobiology that need to be addressed by the community through future research. The three primary objectives of the workshop are (1) to identify high-priority new and emerging research opportunities offered by the sedimentary, geochemical and paleontological records, (2) to develop and prioritize a set of guiding ?grand challenges? for the coming decade of research in the aforementioned sub-disciplines, and (3) delineate key instrumentation and facilities that will needed to support these new and emerging research opportunities.
A scientific community workshop was held July 26-27 at the UC-Davis Tahoe Environmental Research Center, Incline Village, Nevada in order to identify a series of grand challenges and research opportunities in the broader sedimentary geology and geochemistry and paleobiology community for the next decade. The workshop defined six grand research challenges that are poised for major advance and provide opportunities for marked progress toward refining our deep-time and long-term perspective of the nature and variability of the earth system. The common theme through all of these grand challenges is the need for multidisciplinary efforts that brings together observational and modeling studies, which focus on the mechanistic linkages between physical, chemical, and biological processes and that have shaped the Earth’s surface and the ecosystems it supports throughout its history. The Grand Challenges include: The Evolving Earth System 1. What processes have influenced ocean chemistry, circulation and oceanic thermal and chemical gradients, and, in turn, how have major changes in ocean chemistry impacted life & climate across geologic time scales? 2. How has atmospheric composition (greenhouse gases, O2, aerosols) and circulation changed through time and with what impact on Earth systems? 3. What were ecosystem dynamics on a pre-hominim earth? The Co-Evolution of Earth’s Surface and Ecosystems It Supports 4. How have changes in surface processes, landscapes, climate and ecosystems been mechanistically linked through time? The Earth System Response to Change 5. How have the hydrological & carbon cycles interacted under different climate and surface dynamics? 6. What defines major system thresholds in the reorganization of surface processes (e.g, climate, landscapes, life)? The sedimentary geology and geochemistry and paleobiology community is currently well poised to exploit the deep-time sedimentary archive at an unprecedented resolution and intellectual depth given recent advances in several directions of earth sciences. In order to make significant further advances in the six grand challenges, however, will require a scaled-up, fully inter- and cross-disciplinary approach to deep-time studies of the Earth’s crustal carapace. The community is proposing a cross-divisional initiative at NSF that will allow for the requisite synergetic collaborations and force community transformation. The core of this initiative is a deep-time continental drilling program and associated synthesis center that will provide the intellectual and physical support needed to sustain such a program and its associated research. This drilling program, through coordination with existing drilling programs, would provide the link between oceanic-epicontinental records thus permitting evaluation of how surface processes are recorded in these different yet mechanistically linked environments. Such insight is critical to unraveling how environmental, biologic and post-depositional processes are captured in the signatures of marine and paralic proxies. The community further stressed its need for continued efforts in improved geochronology, in particular the EARTHTime initiative. Also critical to bringing the grand challenge research to fruition is a scaled-up effort to develop spatially resolved proxy time-series of improved temporal resolution, precision, and accuracy. A focus on linked terrestrial-marine deep-time records for key intervals of dynamic environmental change is much needed to fully understand the interplay and feedbacks of the surface system dynamics. The optimum approach for sampling appropriate geographic transects, that include proxy records of continental processes and ecosystem dynamics with sufficient resolution and preservational quality to provide the necessary insights, will be through a coordinated continental drilling effort. Further resources for appropriate 3-D seismic studies associated with continental drilling are necessary. Also integral to such studies is the refinement of existing proxies and development of new proxies of surface processes in the atmosphere, ocean, soils, and floral, faunal and microbial communities, in particular where the level of precision and accuracy can be improved. Data-model comparisons are critical to hypotheses testing and for understanding the theory that underpins changes in the deep-time record. In conjunction with proxy efforts, process-based numerical models of Earth’s climate, biogeochemical cycles, ecological interactions, and diversification dynamics must be developed or further refined.
