Nonlinear AVA Inversion Based on a Novel Quadratic Approximation for Fluid Discrimination

<div>Inversion results of synthetic data with different SNR. The black line indicates the initial model, the blue line indicates the inversion result, and the red line indicates the true data. (a) Noise-free, (b) <span class="nowrap"><svg height="8.98583pt" id="M109" style="vertical-align:-0.2324905pt" version="1.1" viewbox="-0.0498162 -8.75334 45.1134 8.98583" width="45.1134pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M409 504C401 567 396 607 392 642C354 654 312 665 266 665C137 665 60 583 60 487C60 374 161 325 225 290C300 250 355 215 355 141C355 68 311 21 235 21C131 21 86 122 71 183L41 176C48 128 61 42 68 21C78 16 93 8 118 0C142 -7 175 -15 216 -15C349 -15 438 69 438 174C438 287 344 333 265 374C186 414 138 449 138 522C138 576 172 631 249 631C336 631 363 562 380 499L409 504Z"></path></g><g transform="matrix(.013,0,0,-0.013,6.005,0)"><path d="M719 650H483V622C553 619 576 606 581 560C585 532 588 487 588 394V148H585L167 650H20V622C67 618 88 610 109 585C127 562 129 557 129 484V264C129 173 126 124 123 93C118 44 92 31 35 28V0H272V28C204 32 181 44 176 95C173 124 170 172 170 264V515H172L598 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Geofluids

fig5

Figure 5

Figure 5: Nonlinear AVA Inversion Based on a Novel Quadratic Approximation for Fluid Discrimination 