Interpretational value of multiattribute display - Marfurt and Daox

wireanticipatedSoftware and s/w Development

Dec 14, 2013 (3 years and 7 months ago)

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Interpretational value of multiattribute display


Kurt J. Marfurt and Toan Dao

The University of Oklahoma

Norman, OK, USA




Today, all 3D interpretation software supports at least 256 colors. 256 colors provide excellent
resolution of seismic amplitude or attribute data that have been properly converted to 8
-
bit
format.
Almost all interpretation software also provides high qua
lity opacity implementation,
allowing an interpreter to co
-
render two attributes, ideally one against a chromatic color bar, the
other against a simple gray scale which renders the first image lighter or darker.


The RGB color gamut is particularly easy
to implement, and is very effective in co
-
rendering
multiple attributes of the same type, with the most common use being the display of three
spectral components, or amplitudes of three angle stacks. Simple digital photography software
provide an economic,

but not very convenient means of generating 24
-
bit RGB color images.
More recently implemented interpretation software vendors, having little legacy data, have
simply adopted OpenGL tools to provide 24
-
bit (and with opacity, 32
-
bit) color directly. These
implementations provide a color depth that can be truly astonishing when imaging 3D
stratigraphic systems.


The HLS color model is most appropriate when one or two attributes modulates a primary
attribute, with lightness, L, being the natural one to map ag
ainst an attribute of spectral
magnitude, dip magnitude, magnitude of deformation,

intensity of anisotropy,

and confidence in
a given colored facies or class. Our preference is to have the weakest (or least confident) features
mapped against pastel colors
, with values corresponding to zero mapped to white. The strongest
values are mapped to a level of lightness, L=0.6. In this manner, we can co
-
render an additional
(3
rd

or 4
th
) attri
bute, such as an edge
-
sensitive attribute such as coherence
using opacity
as well
.


We will begin this webinar with a review of the history of using color display in seismic
interpretation. Then we will illustrate the value of multiattribute display (using only 4096 colors)
in the display of modern seismic attributes, using anim
ation if possible through a suite of data
volumes acquired in the USA and Mexico. We will conclude with a simple review of how to
modulate one attribute with another using simple arithmetic

and demonstrate Toan’s Ocean
implementation.