The Mid-Miocene "Monterey Event": A global productivity increase?

我们研究了中新世中期的“蒙特利事件”(文森特和伯杰，1985)，这是一次持续时间为4.5My的正碳同位素漂移，以帮助更好地理解控制陆地、大气和海洋储集层中碳分布的过程。在极端温暖的时期，δ13C的漂移归因于北太平洋边缘对有机碳的强化封存(同上)。我们的目标是澄清远洋沉积物是否也反映了生产力的提高，这可能是导致δ13C漂移的原因。如果是这样的话，我们的进一步目标是找出造成4.5英里长的营养物质的来源。全球生产率提高的时期。最后，我们的目标是通过D.Groecke对我们样品中大量海洋有机质的δ13C分析(δ13Ccarb和δ13Corg之间的分馏)，调查生产力变化是否与pCO2 atm变化有关(如Pagani等人(1999年)所提出的)。

We investigate the Mid-Miocene “Monterey Event” (Vincent and Berger, 1985), a positive carbon isotope excursion of 4.5 my duration, in order to contribute to a better understanding of the processes that control the distribution of carbon in the terrestrial, atmospheric and marine reservoirs. This δ13C excursion during a period of extreme warmth has been attributed to the enhanced sequestration of organic carbon in the margins of the northern Pacific ocean (op.cit.). We aim to clarify whether pelagic sediments also reflect increased productivity that might have contributed to the δ13C shift. If this is the case, we further aim to identify the sources of nutrients responsible for a 4.5 m.y. period of globally increased productivity. Finally, we aim to investigate if productivity variations can be related to pCO2atm variations (as proposed by Pagani et al.(1999)), by means of δ13C analyses of bulk marine organic matter in our samples by D. Groecke (fractionation between δ13Ccarb and δ13Corg).