Modern engineered systems are increasingly integrated into society, decentralized, and interconnected. However, scale and complexity create unique challenges in system design, such as emergent behavior and unintended consequences. This work investigates the structural characteristics of robustness in complex engineered systems by identifying patterns of under-recognized vulnerabilities at various levels of...
Bridge Creek is a small stream which runs through the central Oregon high desert region. Ranching, the area's primary industry, was degrading conditions in the stream. A group of ranchers and environmentalists, working as part of the Oregon Watershed Improvement Coalition, forged an agreement on what was needed for a...
Bridge Creek is a small stream which runs through the central Oregon high desert region. Ranching, the area's primary industry, was degrading conditions in the stream. A group of ranchers and environmentalists, working as part of the Oregon Watershed Improvement Coalition, forged an agreement on what was needed for a...
Variability in the terrigenous (land-derived) fraction of marine sediments,
including pollen and rock fragments, reflects the effects of regional climate change on
continentally derived runoff, ice extent, vegetation and ocean circulation. The transport of
this continental material to the seafloor must be understood in order to interpret the
terrigenous sediment...
The Cretaceous was a period of extreme climatic conditions accompanied
by major perturbations in ocean-atmosphere biogeochemical cycles. One of the
most intriguing features is the sporadic interruption of normal marine pelagic
sediment deposition by organic rich sediments deposited during oxygen-deficient
conditions (ocean anoxic events OAEs). A current model for the...
Marine sediments exceptionally rich in organic carbon, known as black shales, occur globally but intermittently in well correlated Cretaceous successions. The presence of black shales indicates that sporadic, ocean-wide interruption of normal respiration of marine organic matter during oxygen-deficient conditions has occurred. Submarine volcanism on a massive scale, related to...
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Robert A. Duncan
Marine sediments exceptionally rich in organic carbon, known as
This research focuses on the development of new techniques to explore terrestrial-ocean climate linkages along the Pacific Northwest-northeast Pacific Ocean margin. This is done by investigating river response to climate change and by unraveling this history preserved in continental margin sediments. A significant component of this work centers on developing...