1 Three - Dimensional Facies Analysis using 2 Object - Based Geobody Modeling : A Case Study for 3 the Farewell Formation , Maui Gas Field , Taranaki 4 Basin , New Zealand 5

The early-mid Paleocene Farewell Formation is stratigraphically distributed across the 10 southern Taranaki Basin (STB) which is also encountered within the Maui Gas Field. Using 11 available 3D seismic and well log data, a challenging task to delineate the spatial distribution and 12 geobody patterns of the potential reservoir sands of the formation was performed. Object based 13 modeling coupled with sequential indicator simulation were used to analyze the spatial 14 distribution of facies configuration and a conceptual model was developed based on the outputs 15 from the structurallymodeled grids. The facies modeling followed a hierarchical object-based 16 mechanism which was set to perform with constraints like channel geometry and heterogeneity 17 within the formation. The resultant 3D geobody model showed that the distributary channels, 18 mainly braided geobodies flowed from northeast cutting through several regional normal-fault 19 systems to the southwest. Overbank facies was adhered to the fringe of the channels whereas the 20 floodplain facies was at the periphery of the model. Meandering channel-sand facies were mostly 21 observed at the center of the model flowing in a more random manner, occupying major flow 22 directions of northwest to southwest and southeast to northwest within the model. 23