[First Hit]

International Conference & Exhibition

Datapages, Inc.Print this page

Previous HitPalynofaciesNext Hit Analogues and Applications to Hydrocarbon Exploration in New Zealand


Visual Previous HitkerogenNext Hit and Previous HitpalynofaciesNext Hit analyses are useful tools for determining the origin, composition and petroleum generative potential of organic-rich sedimentary rocks and the depositional conditions for a wide range of sediments and sedimentary rocks. Firstly, we provide examples of analogues to test existing Previous HitpalynofaciesNext Hit models through comparing quantitative Previous HitpalynofaciesNext Hit and environmental data from sediments deposited over the last 1500 yr. Secondly, we use the Previous HitpalynofaciesNext Hit model to interpret the conditions of deposition for a potential Paleocene source rocks in New Zealand's sedimentary basins, the coeval Tartan and Waipawa Formations. Results from the analogue study show that the distribution of particulate organic matter in environments ranging from near-shore to deep-sea is controlled by the distance from the shore and water depth. Phytoclasts and amorphous matter represent the major components of the total assemblage in coastal and shelfal settings; phytoclasts are rare to absent in the distal, deep-water sediments. In deep-water, palynomorphs consist of a selection of organic material, which could result from transport, sorting or grading. In the Great South Basin, Previous HitpalynofaciesNext Hit Previous HitanalysisNext Hit of the Tartan Formation (early Late Paleocene) (10% average TOC) indicates that it was deposited in a marginally marine environment with strong influx of terrestrial plants. Previous HitAnalysisNext Hit of the underlying and overlying units indicates that they were deposited in more distal conditions. The changes observed are best explained by as base-level fall and short-lived regression, including deposition of the Tartan Formation, followed by latest Paleocene–Eocene transgression. To the north, Previous HitanalysisNext Hit from the Tartan Formation in the Canterbury Basin and the Waipawa Formation in the East Coast Basin shows that they share Previous HitpalynofaciesTop and geochemical characteristics, indicating that a base-level fall also controlled the deposition of the these units in northern basins, although it occurred over a wider range of depositional settings. The extent of the area affected by the base-level fall indicates that it was probably caused by eustasy. Associated studies also show that deposition was accompanied by short-lived but pronounced climatic cooling at ~59 Ma. Implications for hydrocarbon potential are that these units may have a larger and possibly more continuous offshore distribution than previously thought.