%ABerryman, J.G.
%ABerge, P.A.
%D1997%K58 GEOSCIENCES; ISOTROPY; MONTE CARLO METHOD; PARAMETRIC ANALYSIS; SEISMIC WAVES; LAYERS; REFLECTION
%MOSTI ID: 303869; Legacy ID: DE98050929
%PMedium: ED; Size: 7 p.; Other: FDE: PDF; PL:
%TAnalysis of thomsen parameters for finely layered VTI media
%Uhttp://www.osti.gov/scitech//servlets/purl/303869-dLCcuo/webviewable/
%XThe range of Thomsen`s anisotropy parameters {epsilon} and {delta} for vertical transversely isotropic (VTI) media when the anisotropy is due to fine layering of isotropic elas-tic materials is considered. We show that {epsilon} lies in the range -3/8 {<=} {epsilon} {<=} {1/2}[-1], for finely lay-ered media having constant density; smaller positive and all negative values of {epsilon} occur for media with large fluctuations in the Lam{acute e} parameter {lambda} We show that sign({delta}) = sign ( - ) for constant density media, so {delta} can be either positive or negative. Among all theoretically possible random media, posi-tive and negative {delta} are equally likely in finely layered media limited to two types of constituent layers. Lay-ered media having large fluctuations in Lam{acute e} {lambda} are the ones most likely to have positive {delta}. Since Gassmann`s results for fluid-saturated porous media show that the effects of fluids influence only the {lambda} Lam{acute e} constant, not the shear modulus {mu}, these results suggest that positive {delta} occurring together with positive but small {epsilon} may be indicative of changing fluid content in layered earth.
%0Conference
%@UCRL-JC--127249; CONF-971111--; Other: ON: DE98050929; TRN: 99:002045
United StatesOther: ON: DE98050929; TRN: 99:002045Mon Feb 04 20:15:59 EST 2008INIS; OSTI as DE98050929LLNL; SCA: 580000; PA: LLNL-97:M98050929; EDB-99:017494; SN: 97001875345English