Determining main carbonate mineralogy, and the primary components of the non carbonate fraction, at three depths in core GC11, collected from the Capricorn Channel.

A gravity core (GC11) was collected from a depth of 502 mbsl within the Capricorn Channel, southern Great Barrier Reef (GBR). Analysis of other parameters revealed the Last Glacial Maximum (LGM) sitting at a depth of ~30cm into the core. Three samples were collected for XRD analysis; at the sediment surface (GC11-0) representing interglacial sediment, at 260cm (GC11-260) also representing interglacial sediment, and from 160cm (GC11-160) - representing glacial sediment. XRD analysis shows that the majority of the interglacial sample (GC11-260) carbonate is made up of calcite. The glacial sample (GC11-160) is only 50% CaCO3 with the rest of the sample made up of quartz and clays.

研究人员于大堡礁（Great Barrier Reef，GBR）南部摩羯水道的502米海平面下深度（meters below sea level，mbsl）处采集了一根重力岩心（GC11）。通过对其他相关参数的分析，确定末次冰盛期（Last Glacial Maximum，LGM）的沉积层位于岩心约30厘米深度位置。本次研究共采集3件样品用于X射线衍射（X-ray Diffraction，XRD）分析：分别为沉积物表层的GC11-0（代表间冰期沉积物）、260厘米深度处的GC11-260（同样对应间冰期沉积物），以及160厘米深度处的GC11-160（对应冰期沉积物）。XRD分析结果显示，间冰期样品GC11-260的碳酸盐组分以方解石为主；冰期样品GC11-160的碳酸钙（CaCO3）占比仅为50%，剩余组分主要为石英与黏土。