Assessment of the Cenozoic Erosion Amount Using Monte Carlo Type-Petroleum Systems Modeling of the Hammerfest Basin, Western Barents Sea

Abstract

The Cenozoic uplift and erosion is often believed to be a major risk factor in hydrocarbon exploration in the Barents Sea causing petroleum redistribution and leakage from filled traps. Therefore, the estimation of erosion amount is an important but often underrepresented task in the basin modeling procedure. The assessment of erosion magnitudes and spatial distribution by geochemical and thermo chronological methods results in very different estimates and/or does not consider uncertainties of input data. In this study, this problem is approached by using Monte Carlo simulation techniques in secondary migration basin modeling. Thereby, amounts of early and late Cenozoic erosion episodes are described by probability distributions and the modeling results were evaluated considering their uncertainty ranges. In addition, overpressure and related leakage scenarios are considered in the petroleum basin models to study their effect on modeling results. It is shown that the early Cenozoic erosion event had a generally higher erosion magnitude than the late Cenozoic event (1.0-1.3 and 0.4-1.2 km respectively). Modeled erosion estimates are not very sensitive to overpressure modeling which is found to affect only the early Cenozoic erosion amount estimates at low degree.