Abstract: 3D Structural and Stratigraphic Frameworks using Acoustic Impedance, Amplitude and EDGE-Enhanced Seismic Volumes
KELSCH, K. D., T. L. HEIDRICK, A. RAUF, and HAZAIRIN, PT Caltex Pacific, Indonesia
Chevron's Edge Detection of Geologic Elements (EDGE) tool produces enhanced geologic images that increase interpretation confidence, accuracy, and reduce interpretation cycle time. EDGE processing calculates differences between amplitudes to enhance both structural and stratigraphic discontinuities. Streamlined 3D volume interpretation processes result in constrained structural and stratigraphic frameworks for reservoir characterization studies and trap development.
Former structural and stratigraphic frameworks were developed using exaggerated 2D time inlines and crosslines and a single 3D volume attribute. This methodology leads to incorrectly picked surfaces, faults and channels, extends reservoir sands laterally beyond their actual limit, and produces inadequate structural models of deep complex trap geometries. Hardware/software advances permit simultaneous use of 3D acoustic impedance, amplitude and EDGE volumes.
Caltex's work process for building structural and stratigraphic frameworks
employ 3D seismic attribute data within a volume interpretational system.
Elements are interpreted using two 3D attribute volumes. Fault picking
is conducted at a 1:1 scale along inline/crossline views from an amplitude
volume and high resolution EDGE timeslices. Faults are catalogued by attribute
and converted to triangulated mesh surfaces prior to sequential voxel-picking
of horizons, channels, clinoforms and fluid contacts. Stratigraphic interpretation
is completed using an amplitude volume interpolated and trimmed to a specific
area or structural compartment. Unlike the EDGE volume, acoustic impedance
volumes enhance lateral discontinuities within pay intervals and guides
the interpreter during 3D picking of stratigraphic eventsO This work process
is repeated for each structural compartment until a 3D earth model is built
for reservoir characterization.
AAPG Search and Discovery Article #90935©1998 AAPG Pacific Section Meeting, Ventura, California