1. Introduction  
2. Data Samples  
2.1. Adopted GES Sample  
2.2. Adopted APOGEE Sample  
3. Metallicity-Abundance Distributions and Analysis Strategy  
4. GMM Decomposition of the GES and APOGEE Samples  
4.1. GES Data Sample  
4.2. Comparison with APOGEE-RC Data  
4.3. GMM Results for Different Stellar Luminosity Classes  
5. The Metal-Poor Thin Disk  
5.1. Vertical Distribution of Disk Stars  
5.2. Rotational Velocity of Disk Stars  
6. Discussion  
7. Conclusions