3-D and 4-D Definition of Structural Fluid Flow Networks in Devonian Carbonates Using Sulfide Tracers: Emanuel Range of the Lennard Shelf, Canning Basin, Western Australia

了解地球上地壳中流体流动的几何形状和性质对许多与社会和工业活动相关的地球科学学科至关重要，包括石油地质学、矿床地质学、水文地质学、地热能和地震危害分析。地壳流体流动通常受断层和断裂网络的构造渗透率控制。尽管通过建模和二维现场研究对断层-断裂流动网络进行了广泛的研究，但对古代流动网络进行的三维现场研究却很少。西澳大利亚坎宁盆地的铅锌矿床为研究地壳流体的三维流动提供了一个独特的天然实验室。当盆地压实脱水时，含金属的盆地卤水沿着断裂网络流动，当流体到达可渗透的活性碳酸盐地层时，沉积金属硫化物矿物。该地区未受矿化后变形的影响。我们建议通过绘制沿断层和裂缝沉积的硫化物矿物的分布，利用出色的二维地表暴露、三维地下暴露、500多公里的金刚石钻芯以及广泛的地震反射、航磁和重力数据，建立古流动网络的三维模型。横切脉关系和岩石学确定的硫化物共生将用于确定矿化事件的相对时间，从而将模型扩展到4-D（时间）。

EAR-0073763Hitzman & NelsonUnderstanding the geometry and nature of fluid flow in the earth's upper crust is critically important to a number of geoscience disciplines related to societal and industrial activities, including petroleum geology, ore deposit geology, hydrogeology, geothermal energy, and seismic hazard analysis. Crustal fluid flow is commonly controlled by structural permeability of fault and fracture networks. Although fault-fracture flow networks have been studied extensively through modeling and 2-D field studies, few 3-D field studies have been undertaken on ancient flow networks. Zn-Pb deposits in the Canning basin of Western Australia provide a unique natural laboratory to investigate crustal fluid flow in 3-D. Metalliferous basinal brines flowed along fault-fracture networks as the basin compacted and dewatered, and deposited metal sulfide minerals when the fluids reached permeable, reactive carbonate formations. The area was unaffected by deformation following mineralization. We propose to build a 3-D model of the paleo-flow network by mapping the distribution of sulfide minerals, deposited along faults and fractures, using superb 2-D surface exposure, 3-D underground exposures, 500+ kilometers of diamond drill core, and extensive seismic reflection, aeromagnetic, and gravity data. Cross-cutting vein relationships and petrographically determined sulfide parageneses will be used to determine the relative timing of mineralizing events, thus extending the model to 4-D (time).