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和性质对于许多与社会和工业活动有关的地学学科至关重要，这些学科包括石油地质学、矿床地质学、水文地质学、地热能和地震灾害分析。地壳流体的流动通常受断层和裂隙网络的构造渗透率控制。尽管人们通过建模和二维野外研究对断层-裂缝性渗流网络进行了广泛的研究，但对古老的渗流网络进行三维野外研究的还很少。西澳大利亚州坎宁盆地的锌铅矿床为研究三维地壳流体流动提供了独特的天然实验室。当盆地压实和脱水时，含金属盆地卤水沿着断层-裂隙网络流动，当流体到达可渗透的、活性碳酸盐地层时，金属硫化物矿物沉积。该地区未受成矿后变形的影响。我们建议通过绘制沿断层和断裂沉积的硫化物矿物的分布，使用优质的二维地表暴露、三维地下暴露、500多公里的钻石钻芯以及广泛的地震反射、航磁和重力数据，来建立古流体网络的三维模型。横切矿脉关系和岩相学确定的硫化物共生体将被用来确定成矿事件的相对时间，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).