SST Crossword

12345678
Across
  1. 5. rich in black soil
  2. 6. undersea mountain
  3. 7. Volcanic mountain
  4. 8. Large stretches of flat land
Down
  1. 1. a low area of land between hills or mountains
  2. 2. High natural elevation
  3. 3. elevated flat land
  4. 4. Frozen rivers