Publications by authors named "Kyle M Samperton"
Article Synopsis
- Since 1952, the Sellafield nuclear complex has released 276 kg of liquid radioactive effluent, mainly containing plutonium, into the Irish Sea, concentrating transuranic activity in the Mudpatch sediments off the Cumbrian coast.
- Leaching experiments on contaminated sediments from the Esk Estuary revealed that plutonium (Pu) leaching is significantly higher under anoxic conditions, suggesting environmental factors greatly influence its mobility.
- Microbial communities in the sediments change with varying conditions, and results show that Pu leaching is greater in shallow sediments and does not correlate with total Pu, indicating a complex biogeochemical behavior.
Temporal correlation between some continental flood basalt eruptions and mass extinctions has been proposed to indicate causality, with eruptive volatile release driving environmental degradation and extinction. We tested this model for the Deccan Traps flood basalt province, which, along with the Chicxulub bolide impact, is implicated in the Cretaceous-Paleogene (K-Pg) extinction approximately 66 million years ago. We estimated Deccan eruption rates with uranium-lead (U-Pb) zircon geochronology and resolved four high-volume eruptive periods.
View Article and Find Full Text PDFThe continental crust is central to the biological and geological history of Earth. However, crustal heterogeneity has prevented a thorough geochemical comparison of its primary igneous building blocks-volcanic and plutonic rocks-and the processes by which they differentiate to felsic compositions. Our analysis of a comprehensive global data set of volcanic and plutonic whole-rock geochemistry shows that differentiation trends from primitive basaltic to felsic compositions for volcanic versus plutonic samples are generally indistinguishable in subduction-zone settings, but are divergent in continental rifts.
View Article and Find Full Text PDFThe Chicxulub asteroid impact (Mexico) and the eruption of the massive Deccan volcanic province (India) are two proposed causes of the end-Cretaceous mass extinction, which includes the demise of nonavian dinosaurs. Despite widespread acceptance of the impact hypothesis, the lack of a high-resolution eruption timeline for the Deccan basalts has prevented full assessment of their relationship to the mass extinction. Here we apply uranium-lead (U-Pb) zircon geochronology to Deccan rocks and show that the main phase of eruptions initiated ~250,000 years before the Cretaceous-Paleogene boundary and that >1.
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