Bivalve Paleoecology: Key to the Environmental Stratigraphyof a Pliocene Sedimentary Sequence

在以往的研究过程中， 西方的地理学、灭绝和系统进化 大西洋双壳类在晚第三纪的时间，我已经取得了 大量上新世早期贝壳动物群 位于佛罗里达萨拉索塔的矿井。 这种动物群的壮观之处在于 丰富度（超过1000种软体动物，约180 其中，双壳类动物的数量最多，保存也最好。 在我的工作过程中，我得出结论， 坑中的相序列记录了 屏障-岛屿-泻湖复合体，体现了瓦尔特定律。 这种类型的海侵层序在 由于海平面相对快速上升， 通常破坏障壁岛和泻湖相， 他们跳到内陆。 我正在开发一个模型来解释为什么 萨拉索塔的海侵序列得以保存 我认为这一模式具有普遍意义。 这项建议 是为了资助更详细的研究， 萨拉索塔矿坑的地层单位， 收集其动物群，并充分发展其 地层模式 最后，我还将制作一个 关于双壳类动物的分类学-地理学专著， 它代表了很少被研究的 北部著名的动物群（北方佛罗里达到弗吉尼亚： 杰克逊海崖、杜普林和约克镇动物群）。 至关重要 萨拉索塔的实地工作现在就可以进行，因为 坑很快就会被淹没。

In the course of previous research on patterns of biogeography, extinction, and phyletic evolution for Western Atlantic Bivalvia during late Neogene time, I have made extensive collections of the early Pliocene fauna of a shell pit at Sarasota, Florida. This fauna is spectacular for its richness (more than a thousand species of mollusks, about 180 of them bivalves) and for its excellent state of preservation. In the course of my work, I have concluded that the vertical sequence of facies in the pit records the transgression of a barrier-island-lagoon complex, exemplifying Walther's Law. Transgressive sequences of this type are rare in the stratigraphic record because rapid relative rises of sea level usually destroy barrier island and lagoonal facies or cause them to jump inland. I am developing a model to explain why the transgressive sequence has been preserved at Sarasota - a model that I believe has general significance . This proposal is for funding to support more detailed study of the stratigraphic units in the Sarasota pit, more thorough collection of their faunas, and full development of the stratigraphic model. Ultimately, I will also produce a taxonomic-biogeographic monograph on the total bivalve fauna, which represents the little-studied temporal equivalent of well-known faunas to the north (northern Florida to Virginia: the Jackson Bluff, Duplin and Yorktown faunas). It is crucial that the field work in Sarasota be conducted now because the pit will soon be flooded.