A New Method for Research on Unsteady Pressure Dynamics and Productivity of Ultralow-Permeability Reservoirs

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109 -12 232 -12C263 -12 332 6 395 84L380 106ZM225 412C281 412 315 364 314 312C314 297 308 292 290 292C232 290 176 289 120 289C135 370 180 412 225 412Z"></path></g><g transform="matrix(.0065,0,0,-0.0065,59.076,-3.641)"><path d="M99 437H52L25 408L28 397H99V104C99 38 91 32 32 26V0H246V25C185 32 178 38 178 104V397H365V104C365 38 358 32 303 25V0H526V25C451 32 444 37 444 104V397H555C565 404 568 428 563 437H444V471C443 562 453 609 466 629C476 647 492 661 518 661C551 661 581 639 600 620C609 611 619 612 629 620C637 626 647 636 650 644C654 654 654 666 645 677C627 697 597 710 564 712C521 707 476 686 432 642C412 664 374 688 316 690C269 685 230 668 190 636C139 596 120 551 111 525C104 505 99 477 99 449V437ZM365 437H178V461C178 537 192 580 209 605C223 627 245 648 283 648C336 648 374 615 394 585C384 566 378 550 374 533C369 516 365 488 365 456V437Z"></path></g></svg><br/>Exponential form</td><td class="align_center"><svg height="29.6603pt" id="M2" style="vertical-align:-12.5166pt" version="1.1" 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371C124 371 121 357 117 341L55 97C32 5 46 -12 70 -12C108 -12 191 51 227 95Z"></path></g><g transform="matrix(.013,0,0,-0.013,114.809,0)"><path d="M275 270C275 450 212 609 64 710L45 686C145 604 203 442 203 270S147 -63 45 -147L64 -170C213 -68 275 89 275 270Z"></path></g></svg><br/>Stress-sensitive coefficient method</td></tr><tr class="table-tr"><td colspan="3"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

<div>Permeability characterization method.</div>

Geofluids

tab1

Table 1

Table 1: A New Method for Research on Unsteady Pressure Dynamics and Productivity of Ultralow-Permeability Reservoirs 