The radial velocity dispersion of 67 RR Lyrae and BHB stars that are more than 4 kpc above the galactic plane at the North Galactic Pole is \approx 110 km s ^ { -1 } and shows no trend with Z ( the height above the galactic plane ) .
Nine stars with Z \leq 4 kpc show a smaller velocity dispersion ( 40 \pm 9 km s ^ { -1 } ) as is to be expected if they mostly belong to a population with a flatter distribution .
Both RR Lyrae stars and BHB stars show evidence of stream motion ; the most significant is in fields RR2 and RR3 where 24 stars in the range 4.0 \leq Z \leq 11.0 kpc have a mean radial velocity of - 59 \pm 16 km s ^ { -1 } .
Three halo stars in field RR 2 appear to be part of a moving group with a common radial velocity of - 90 km s ^ { -1 } .
The streaming phenomenon therefore occurs over a range of spatial scales .
The BHB and RR Lyrae stars in our sample both have a similar range of metallicity ( - 1.2 \leq [ Fe/H ] \leq - 2.2 ) .
Proper Motions of BHB stars in fields SA 57 ( NGP ) and the Anticenter field ( RR 7 ) ( both of which lie close to the meridional plane of the Galaxy ) show that the stars that have Z < 4 kpc as well as those with Z > 4 kpc have a Galactic V motion that is < - 200 km/s and which is characteristic of the halo .
Thus the stars that have a flatter distribution are really halo stars and not members of the metal-weak thick-disk .