Metal abundances are derived for 60 newly discovered RR Lyraes in three Lick Astrographic Survey fields at three Galactic altitudes (l,b): (86 deg, +35 deg), (52 deg, +35 deg), and (18 deg, +25 deg). In addition, Delta S values were obtained for five nearby field RR Lyraes which have no previous records, and improved Delta S values were obtained for 24 nearby RR Lyraes. These values, in conjunction with data from previous Lick surveys and those obtained by Saha and Oke (1985), were used to study the nature of the Galactic halo in the galactocentric distance range 4-30 kpc, based on 171 Lyraes. It was found that the Galactic halo undergoes a change in the behavior of the Fe/H ratio at the position of the solar circle.
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Suntzeff et al. (1991) studied this question.