INTERSTELLAR ABUNDANCES IN THE MAGELLANIC CLOUDS .1. GHRS OBSERVATIONS OF THE SMALL-MAGELLANIC-CLOUD STAR SK-108

We present HST GHRS echelle-B and G160M spectra of the Wolf-Rayet bina ry Sk 108, located in the northeastern part of the main ''bar'' of the Small Magellanic Cloud. The spectra show interstellar absorption from C I, O I, Si II, Si II, S II, P II, Cr II, Mn II, Fe II, Ni II, and Zn II. We find at least 25 interstellar components, which may be group ed via similar kinematics and/or similar relative heavy element abunda nces into two sets arising in the Galactic disk and halo, plus three s ets located in the SMC. The SMC component groups may correspond to lar ge-scale SMC gas complexes identified in H I 21 cm emission surveys. T he relative gas phase abundances for Si II, Cr II, Mn II, Fe II, Ni II , and Zn II found for the SMC interstellar components are similar to t hose found for interstellar clouds in the Galactic halo. Since the rel ative total abundances for those elements found for F-G supergiants an d gaseous nebulae in the SMC are similar to those present in comparabl e Galactic objects, we conclude that the interstellar depletion patter ns are also similar in the SMC and in the Galactic halo clouds, despit e the significantly lower metallicity and dust-to-gas ratio in the SMC . We do not see the distinctive depletion patterns commonly found for cold and warm clouds in the Galactic disk for any of the SMC component s along the line of sight to Sk 108. We discuss some implications of t hese results for understanding the abundances found for QSO absorption -line systems and conclude that both nucleosynthetic and depletion eff ects contribute to the observed abundances-to different degrees for di fferent systems.