Abstract
Salt deformation has been the topic of numerous studies through the 20th century and up until present because of
the close relation between commercial hydrocarbons and salt structure provinces of the world (Hudec & Jackson,
2007). The fault distribution in sediments above salt structures influences among other things the productivity
due to the segmentation of the reservoir (Stewart 2006). 3D seismic data above salt structures can map such fault
patterns in great detail and studies have shown that a variety of fault patterns exists. Yet, most patterns fall between
two end members: concentric and radiating fault patterns. Here we use a modified version of the numerical
spring-slider model introduced by Malthe-Sørenssen et al.(1998a) for simulating the emergence of small scale
faults and fractures above a rising salt structure. The three-dimensional spring-slider model enables us to control
the rheology of the deforming overburden, the mechanical coupling between the overburden and the underlying
salt, as well as the kinematics of the moving salt structure. In this presentation, we demonstrate how the horizontal
component on the salt motion influences the fracture patterns within the overburden.
The modeling shows that purely vertical movement of the salt introduces a mesh of concentric normal faults in
the overburden, and that the frequency of radiating faults increases with the amount of lateral movements across
the salt-overburden interface. The two end-member fault patterns (concentric vs. radiating) can thus be linked to
two different styles of salt movement: i) the vertical rising of a salt indenter and ii) the inflation of a ‘salt-balloon’
beneath the deformed strata.
The results are in accordance with published analogue and theoretical models, as well as natural systems, and the
model may - when used appropriately - provide new insight into how the internal dynamics of the salt in a structure
controls the generation of fault patterns above the structure. The model is thus an important contribution to the
understanding of small-scale faults, which may be unresolved by seismic data when the hydrocarbon production
from reservoirs located above salt structures is optimized.
the close relation between commercial hydrocarbons and salt structure provinces of the world (Hudec & Jackson,
2007). The fault distribution in sediments above salt structures influences among other things the productivity
due to the segmentation of the reservoir (Stewart 2006). 3D seismic data above salt structures can map such fault
patterns in great detail and studies have shown that a variety of fault patterns exists. Yet, most patterns fall between
two end members: concentric and radiating fault patterns. Here we use a modified version of the numerical
spring-slider model introduced by Malthe-Sørenssen et al.(1998a) for simulating the emergence of small scale
faults and fractures above a rising salt structure. The three-dimensional spring-slider model enables us to control
the rheology of the deforming overburden, the mechanical coupling between the overburden and the underlying
salt, as well as the kinematics of the moving salt structure. In this presentation, we demonstrate how the horizontal
component on the salt motion influences the fracture patterns within the overburden.
The modeling shows that purely vertical movement of the salt introduces a mesh of concentric normal faults in
the overburden, and that the frequency of radiating faults increases with the amount of lateral movements across
the salt-overburden interface. The two end-member fault patterns (concentric vs. radiating) can thus be linked to
two different styles of salt movement: i) the vertical rising of a salt indenter and ii) the inflation of a ‘salt-balloon’
beneath the deformed strata.
The results are in accordance with published analogue and theoretical models, as well as natural systems, and the
model may - when used appropriately - provide new insight into how the internal dynamics of the salt in a structure
controls the generation of fault patterns above the structure. The model is thus an important contribution to the
understanding of small-scale faults, which may be unresolved by seismic data when the hydrocarbon production
from reservoirs located above salt structures is optimized.
| Original language | English |
|---|---|
| Publication date | 2012 |
| Number of pages | 1 |
| Publication status | Published - 2012 |
| Event | European Geophysical Union (EGU) 2012 General Assembly - Vienna, Austria Duration: 22 Apr 2012 → 27 Apr 2012 |
Conference
| Conference | European Geophysical Union (EGU) 2012 General Assembly |
|---|---|
| Country/Territory | Austria |
| City | Vienna |
| Period | 22/04/2012 → 27/04/2012 |