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In this work we combine spectroscopic information from the \textit{SkyMappersurvey for Extremely Metal-Poor stars} and astrometry from Gaia DR2 toinvestigate the kinematics of a sample of 475 stars with a metallicity range of$ -6.5 \leq \rm [Fe/H] \leq -2.05$ dex. Exploiting the action map, we identify16 and 40 stars dynamically consistent with the \textit{Gaia Sausage} and\textit{Gaia Sequoia} accretion events, respectively. The most metal-poor ofthese candidates have metallicities of $\rm [Fe/H]=-3.31$ and $\rm[Fe/H]=-3.74$, respectively, helping to define the low-metallicity tail of theprogenitors involved in the accretion events. We also find, consistent withother studies, that $\sim$21\% of the sample have orbits that remain confinedto within 3~kpc of the Galactic plane, i.e., |Z$_{max}$| $\leq$ 3~kpc. Ofparticular interest is a sub-sample ($\sim$11\% of the total) of low|Z$_{max}$| stars with low eccentricities and prograde motions. The lowestmetallicity of these stars has [Fe/H] = --4.30 and the sub-sample is bestinterpreted as the very low-metallicity tail of the metal-weak thick diskpopulation. The low |Z$_{max}$|, low eccentricity stars with retrograde orbitsare likely accreted, while the low |Z$_{max}$|, high eccentricity pro- andretrograde stars are plausibly associated with the \textit{Gaia Sausage}system. We find that a small fraction of our sample ($\sim$4\% of the total) islikely escaping from the Galaxy, and postulate that these stars have gainedenergy from gravitational interactions that occur when infalling dwarf galaxiesare tidally disrupted.

Exploring the Galaxy's halo and very metal-weak thick disk with SkyMapper and Gaia DR2