en Seismic Geotechnique Seismic Geotechnique Research Paper Research Paper This paper presents time domain fundamental solutions for the extended Biot's dynamic formulations of two-dimensional (2D) unsaturated poroelasticity. Unsaturated porous media is considered as a porous media in which the voids are saturated with two immiscible fluids, i.e. liquid and gas. At first, the corresponding explicit Laplace transform domain fundamental solution is obtained in terms of skeleton displacements, as well as liquid and gas pressures. Subsequently, the closed-form time domain fundamental solutions are derived by analytical inversion of the Laplace transform domain solutions. Finally, a set of numerical results are presented which verifies the accuracy of the analytically inversed transient fundamental solution and demonstrates some salient features of the elastic waves in unsaturated media.. Unsaturated poroelastodynamics, Wave propagation, Fundamental solution, Boundary element method, Twodimensional problem 110 133 http://ijce.iust.ac.ir/browse.php?a_code=A-10-930-1&slc_lang=en&sid=1 I. Ashayeri i.ashayeri@razi.ac.ir 180031947532846009379 180031947532846009379 Yes Assistant Professor, Civil Engineering Department, School of Engineering, Razi University, Taghebostan, Daneshgah Blvd., Kermanshah, Iran M. Kamalian kamalian@iiees.ac.ir 180031947532846009380 180031947532846009380 No Associate Professor, Geotechnical Research Center, International Institute of Earthquake Engineering & Seismology (IIEES), No. 26 Arghavan St., North Dibaji St. Tehran, Iran M. K Jafari jafari@iiees.ac.ir 180031947532846009381 180031947532846009381 No Professor, Geotechnical Research Center, IIEES, No. 26 Arghavan St., North Dibaji St. Tehran, Iran M. Biglari m.biglari@razi.ac.ir 180031947532846009382 180031947532846009382 No Assistant Professor, Civil Engineering Department, School of Engineering, Razi University, Taghebostan, Daneshgah Blvd., Kermanshah, Iran Ma. Mirmohammad Sadeghi msadeghi84@yahoo.com 180031947532846009383 180031947532846009383 No Assistant Professor, Isfahan Higher Education And Research Institute (IHEARI), Isfahan, Iran