Geoscience Australia Marine Survey GA0332 (SS05/2011): Natural hydrocarbon seepage survey of the offshore northern Perth Basin - Chlorophyll a, b and c and phaeophytin a of seabed sediments.

In September and October of 2011 Geoscience Australia surveyed part of the offshore northern Perth Basin in order to map potential sites of natural hydrocarbon seepage. The primary objectives of the survey were to map the spatial distribution of seepage sites and characterise the nature of the seepage at these sites (gas vs oil, macroseepage vs microseepage; palaeo vs modern day seepage) on the basis of: acoustic signatures in the water column, shallow subsurface and on the seabed; geochemical signatures in rock and sediment samples and the water column; and biological signatures on the seabed. Areas of potential natural hydrocarbon seepage that were surveyed included proven (drilled) oil and gas accumulations, a breached structure, undrilled hydrocarbon prospects, and areas with potential signatures of fluid seepage identified in seismic, satellite remote sensing and multibeam bathymetry data. Within each of these areas the survey acquired: water column measurements with the CTD; acoustic data with single- and multi-beam echosounders, sidescan sonar and sub-bottom profiler (sidescan not acquired in Area F as it was too deep in places); and sediment and biological samples with the Smith-McIntyre Grab. In addition, data were collected with a remotely operated vehicle (ROV), integrated hydrocarbon sensor array, and CO2 sensor in selected areas. Sampling with the gravity corer had limited success in many of the more shallow areas (A-E) due to the coarse sandy nature of the seabed sediments. This dataset comprises chlorophyll a,b, and c and phaeophyton a measurements from the surface 0.5 cm of seabed sediments

2011年9月至10月，澳大利亚地质调查局（Geoscience Australia）对珀斯盆地北部近海部分区域开展勘测，旨在绘制天然烃类渗漏的潜在点位分布图。
本次勘测的核心目标为：基于水体、浅层地下及海底的声学特征，岩石、沉积物样品与水体中的地球化学特征，以及海底的生物特征三类依据，绘制渗漏点位的空间分布，并表征各点位的渗漏性质（天然气与石油、宏观渗漏与微观渗漏、古渗漏与现代渗漏）。
本次勘测覆盖的天然烃类渗漏潜在区域包括：已探明（经钻探）的油气聚集区、一处破损构造、未钻探的油气远景区块，以及经地震、卫星遥感与多波束测深数据识别出的流体渗漏潜在特征区域。
在上述各区域内，本次勘测采集了以下数据：使用温盐深仪（CTD）开展水体测量；利用单波束、多波束回声测深仪、侧扫声呐与浅地层剖面仪采集声学数据（注：F区域因局部水深过深，未获取侧扫声呐数据）；使用Smith-McIntyre采泥器采集沉积物与生物样品。此外，在选定区域内，还通过遥控水下机器人（ROV）、集成烃类传感器阵列与CO₂传感器完成了数据采集。
由于海底沉积物以粗砂质为主，使用重力取芯器开展的采样在A至E等多数浅水区效果有限。
本数据集包含海底表层0.5厘米沉积物中的叶绿素a、b、c以及褐藻素a的测定数据。