A very peculiar damage patterns have been reported during Northridge earthquake of 1994 and Nisqually earthquake of 2001 caused by basement focusing. Similarly, basement de-focusing may cause lesser damage than the expectations but such inferences have not been reported. Further, as far as we know, no theoretical study related to de-focusing effects of anticlinal basement topography (ABT) is available in the literature. In order to fulfill this gap, this article presents the combined effects of sediment rheology and ABT on the SH-and SV-waves characteristics. The simulated results revealed an increase of de-amplification factors with distance travelled in basin above the ABT. The computed snapshots also confirmed amplitude de-amplification, diffraction and mode conversion of SV-wave. Elastic response revealed that the de-amplification factors caused by ABT were not frequency dependent. The average spectral de-amplification factors were more or less same for both the waves even after strong mode conversion of SV-wave at the lower part of ABT. Based on simulated results, it was inferred that the incorporation of effects of ABT in seismic hazard assessment is equally important as that of synclinal asement topography (SBT) effects for cost effective earthquake engineering.Fokusiranje potresnih valova topografijom pripadnih strukturnih bazena uzrokova¬lo je neobičnu razdiobu šteta koja je opažena nakon potresa u Northridgeu 1994. i Nisqualliyu 2001. godine. U skladu s time moguće je očekivati i defokusiranje valova potresa antiklinalnom bazenskom topografijom (ABT), ali, koliko nam je poznato, do sada nije objavljena niti jedna studija koja bi se bavila tim problemom. Kako bismo ispunili tu prazninu, ovdje smo razmotrili kombinirani utjecaj reologije sedimenata i ABT na svojstva SH i SV-valova. Rezultati simulacije ukazuju na povećanje deamplifikacije s udaljenosti koju valovi prevale u bazenu iznad ABT. Sintetizirani seizmogrami također potvrđuju deamplifikaciju amplituda, difrakciju te konverziju modova u slučaju SV-valova. Deam¬plifikacija ne ovisi o frekvenciji. Prosječni spektralni faktori deamplifikacije su gotovo jednaki za obje vrste valova, čak i nakon jake konverzije SV-valova u donjim dijelovima ABT. Na temelju simulacija zaključeno je da su efekti ABT u procjeni potresne opas¬nosti za učinkovito porotupotresno projektiranje jednako važni kao i efekti sinklinalne topografije (SBT)
