Stochastic simulations of karst networks with Lindenmayer systems.

in: 35th Gocad Meeting - 2015 RING Meeting, ASGA

Abstract

Some major hydrocarbon reservoirs are contained within paleokarsts and are influenced by the highly complex network geometries of the past karstic conduits. Those geometries are most of the time unknown and numerical simulations allow to better assess the uncertainty associated to those reservoirs. Several methods have been developed to simulate karstic systems but they mainly focus on branchwork karst networks. Anastomotic patterns are also observed in a significant proportion of karstic networks. Their singular connectivity implies a different response in the oil extraction process, and, thus, needs to be considered. This paper introduces a new object-based method to stochastically simulate karst networks with both branchwork and anastomotic patterns. Based on the Lindenmayer system (L-system), this method is composed of two steps. First, an intermediate karst network with only branchwork pattern is simulated. In a second time, some conduits are reconnected one by one on other conduits of the intermediate network. The very first results are two dimensional karst networks composed of some branching parts and anastomoses. This object-based method allows to generate several models reproducing the particular connectivity of complex karst networks mixing different patterns. Uncontrolled intersections between conduits sometimes appear. They could besides be limited by introducing a repulsion between the conduits. This work gives a basis for the simulation of 2.5D karst networks with possible integration of hard and soft data.

Download / Links

BibTeX Reference

@INPROCEEDINGS{AnquezGM2015,
    author = { Anquez, Pierre and Rongier, Guillaume and Collon, Pauline },
     title = { Stochastic simulations of karst networks with Lindenmayer systems. },
 booktitle = { 35th Gocad Meeting - 2015 RING Meeting },
      year = { 2015 },
 publisher = { ASGA },
  abstract = { Some major hydrocarbon reservoirs are contained within paleokarsts and are influenced by the highly complex network geometries of the past karstic conduits. Those geometries are most of the time unknown and numerical simulations allow to better assess the uncertainty associated to those reservoirs. Several methods have been developed to simulate karstic systems but they mainly focus on branchwork karst networks. Anastomotic patterns are also observed in a significant proportion of karstic networks. Their singular connectivity implies a different response in the oil extraction process, and, thus, needs to be considered. This paper introduces a new object-based method to stochastically simulate karst networks with both branchwork and anastomotic patterns. Based on the Lindenmayer system (L-system), this method is composed of two steps. First, an intermediate karst network with only branchwork pattern is simulated. In a second time, some conduits are reconnected one by one on other conduits of the intermediate network. The very first results are two dimensional karst networks composed of some branching parts and anastomoses. This object-based method allows to generate several models reproducing the particular connectivity of complex karst networks mixing different patterns. Uncontrolled intersections between conduits sometimes appear. They could besides be limited by introducing a repulsion between the conduits. This work gives a basis for the simulation of 2.5D karst networks with possible integration of hard and soft data. }
}