The Internal Stratigraphy of K/T Boundary Sediments and Implications for their Provenance

本研究将研究 白垩纪/第三纪界线沉积物沉积在原始- 加勒比区域确定其来源的方式， 它们是如何被运输的，以及当地的条件如何影响 他们的沉积。 特别是，我们将确定 冲击熔体小球的分布，两者都是 地层高度和与其源的距离;确定 冲击熔融球玻璃的组成，无论它们是否变化 与地层高度或与其源的距离，以及 根据它们的成分推断它们的出处;确定 冲击矿物相（如石英，长石， 和尖晶石）与地层高度的关系，推断其物源; 使用此信息来确定可用于 评估边界沉积物的存款是否未受扰动，或 已被重新加工;并确定总厚度 未受扰动的边界沉积物 这些边界的观察 沉积物将与喷出物的理论计算相结合 运输 综合研究应确定近似的 源火山口的位置和目标的岩性 材料，这两者都应该决定是否希克苏鲁布 结构，我们已经提出了终端的位置 白垩纪撞击，是一个可行的候选者。 研究还应 广泛应用于大型（100 公里）的陨石坑，这是一个目前知之甚少的问题 时间

This study will examine the stratigraphy of Cretaceous/Tertiary boundary sediments deposited in the proto- Caribbean region to determine their provenance, the way in which they were transported, and how local conditions may have influenced their deposition. In particular, we will determine the size distribution of impact melt spherules, both as a function of stratigraphic height and with distance from their source; determine the compositions of impact melt spherule glasses, whether they vary with stratigraphic height or with distance from their source, and infer their provenance based on their compositions; determine the distribution of shocked mineral phases (such as quartz, feldspar, and spinel) with stratigraphic height and infer their provenance; use this information to determine criteria which can be used to assess whether a deposit of boundary sediments is undisturbed or has been reworked; and determine the overall thicknesses of undisturbed boundary sediments. These observations of boundary sediments will be coupled with theoretical calculations of ejecta transport. The combined studies should identify the approximate location of the source crater and the lithologies of the target material, both of which should determine whether the Chicxulub structure, which we have proposed to be the location of a terminal Cretaceous impact, is a viable candidate. The study should also have wide application to the deposition of ejecta from large (100 km) craters, a subject which is poorly understood at the present time.