SGER: The Clathrate Study System

包合物是由水和水的混合物组成的冰状结晶固体。 低分子量气体分子。 因为独特的 压力场和温度场，在其中它们是稳定的， 在大陆坡和海隆，笼形物往往是丰富的 深海中的沉积物 由此产生的固体沉淀 在海洋沉积物中的包合物是可检测的， 底部平行反射体的出现， 地震反射记录通常与海洋平行 底部，并切断其他沉积物反射。 底部 平行反射器显然代表了 笼形稳定场 在该反射器下方， 分解成淡水和溶解气体。 很少有来自深海的笼形化合物原始样本 已经被充分分析，因为包合物倾向于分解 当它被带到海面上时，最近，海洋 钻井计划已经开发了一种压力取心筒， 能够提取一米长的海洋沉积物样本 并将材料返回钻井船， 压力 在最近对该系统的工程测试中， 在南海海沟中采集了原状样品。 的 本奖项将支持初步发展的 必要的分析技术来检查这个意想不到的样本 在充分记录化学反应和条件方面非常重要 以及在评估包合物气体释放到 海平面变化时的大气。

Clathrates are ice-like, crystalline solids composed of water and low molecular weight gas molecules. Because of the unique pressure and temperature fields in which they are stable, clathrates tend to be abundant in continental slope and rise sediments in the deep sea. The resulting precipitation of solid clathrates within marine sediments is detectable from the occurrence of bottom-parallel reflectors which are visible in seismic reflection records, are generally parallel to the ocean bottom, and cut across other sediment reflections. The bottom parallel reflector apparently represents the base of the clathrate stability field. Below this reflector the clathrate decomposes into fresh water and dissolved gas. Few pristine samples of clathrates from the deep-sea have ever been fully analyzed, since the clathrates tends to decompose rapidly when brought to the sea surface. Recently the Ocean Drilling Program has developed a pressure core barrel which is capable of retrieving a one meter long sample of marine sediment and returning the material to the drillship under in situ pressure. During a recent engineering test of this system, an undisturbed sample was recovered from the Nankai Trench. the present award will support preliminary development of the necessary analytical techniques to examine this unexpected sample important in fully documenting chemical reactions and conditions and in evaluating the release of clathrates gasses to the atmosphere during sea-level changes.