Joint U.S.-Croatian Cooperative Research Project: Greenhouse and Transitional Climates in 50 m.y. Carbonate Record of the Late Jurassic-Early Cretaceous Dinaric Platform Croatia

美国-克罗地亚联合合作研究项目：50 年温室效应和转型气候

• 批准号: 0639523
• 负责人: James Read
• 金额: $ 18.21万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-04-01 至 2012-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0639523&HistoricalAwards=false
• 关键词: Joint; U.S.; Croatian; Cooperative; Research

Geoscientists have tended to view the Mesozoic as a long ice-free time of global greenhouse warmth, but there is increasing awareness that the warm climate may have been interrupted by cooler periods and ice buildup. The ancient Dinaric Platform, Croatia is 7 km thick carbonate platform like the Bahamas. However because of uplift, its superb sedimentary record of global climate change is exposed at the surface and can be studied without deep drilling. The shallow water platform recorded many of the sea level fluctuations of the 50 million year Late Jurassic and Early Cretaceous (150 to 100 million years ago), and can be used to define greenhouse times when the earth lacked ice sheets and sea levels underwent many small sea level fluctuations, and times of transition when the earth had moderate sized ice sheets, and fewer, but larger sea level changes (waxing and waning of small ice sheets). The project will document the frequency and magnitude of sea level and climate change from the sedimentary succession. Fossils, and Sr isotopes will be used to date the succession and stable isotopes of carbon and oxygen will be used to document changes in biologic production, burial of organic carbon, and possible waxing and waning of small ice sheets. Estimates of sea level changes will be made using computer simulations of the stratigraphy, which will allow us to greatly refine the climate changes during this time period. The project should increase our understanding of global climate change during times of global greenhouse, and mode of transitions into cooler phases.

地球科学家倾向于将中生代视为全球温室效应的漫长无冰期，但越来越多的人意识到温暖的气候可能被较冷的时期和冰的积累所打断。克罗地亚的古迪纳拉克台地是一个7公里厚的碳酸盐台地，就像巴哈马一样。然而，由于隆起，其极好的全球气候变化沉积记录暴露在地表，无需深钻即可进行研究。浅水平台记录了5000万年晚侏罗世和早白垩世的许多海平面波动（1.5亿至1亿年前），并可用于定义温室时代，当时地球缺乏冰盖，海平面经历了许多小的海平面波动，以及过渡时期，当时地球有中等大小的冰盖，更少，但海平面变化更大（小冰盖的盈亏）。该项目将记录海平面的频率和幅度以及沉积序列引起的气候变化。化石和锶同位素将被用来确定演替的日期，碳和氧的稳定同位素将被用来记录生物生产、有机碳的埋藏以及小冰盖可能的盈亏变化。海平面变化的估计将使用计算机模拟地层学，这将使我们能够大大改善这一时期的气候变化。该项目将增加我们对全球温室效应时期全球气候变化的理解，以及向较冷阶段过渡的模式。