Degradation and Transport of Recent Crinoid Ossicles at San Salvador, Bahamas: Part 2, the Winter Season

鸡冠状骨骼元素在现代海底沉积物中是一种罕见的成分，但古代鸡冠状听骨通常足够丰富，足以成为海相岩石的主要成分。因此，对独立听骨化石过程的研究对沉积学家和古生物学家都很重要。为了确定龙骨小骨就地降解的影响，这些元素将被粘在有机玻璃板上，并固定在海底的混凝土半球上。听骨还将被粘在垂直埋在海底沉积物中的有机玻璃棒上，以研究埋葬的效果。这些技术已经在夏季几个月(1991年3-9月)的生物退化研究中证明是有效的。目前正在利用留在海底5天至6个月的听骨来研究生物的寄生和结壳及其对海龙骨方解石立体结构的影响。拟议的研究将以冬季月份为重点，采用同样的方法。在夏季还没有直接观察到听小骨的运输，但预计将成为拟议研究的主要部分。染料将被释放到水中，颗粒将被污染和监测，设计的沉积物捕集器将被用来对牵引和悬浮物进行采样，直接和间接地测量听骨运输。此外，将从海岸到陆架边缘的横断面上采集沉积物样本，并检查是否有从其居住地运送来的听骨。

Crinoid skeletal elements are a rare component in modern seafloor sediment, but ancient crinoid ossicles are commonly abundant enough to be major constituents of marine rocks. Thus, the study of fossilization processes of separate ossicles is important for sedimentologists as well as for paleontologists. In order to determine the effects of in-place degradation of crinoid ossicles, the elements will be glued to plexiglass plates and fastened to concrete hemispheres on the seafloor. Ossicles will also be glued to plexiglass rods buried vertically in the seafloor sediment to study the effects of burial. These techniques have already proven effective in a study of biologic degradation over the summer months (March-September, 1991). Infesting and encrusting organisms and their effects on the crinoid's calcite stereom are currently being studied using ossicles left on the seafloor for periods from 5 days to 6 months. The proposed research will focus on the winter months, using the same approach. Transport of ossicles has not been observed directly in the summer, but is expected to be a major part of the proposed research. Dye will be released into the water, grains will be stained and monitored, and sediment traps designed to sample both traction and suspended load will be used to measure ossicle transport directly and indirectly. In addition, sediment samples will be taken along transect from shore to shelf edge, and examined for ossicles transported from their living sites.