21. .. . a large portion of the Woongarra land contained more or less loose rocks . 22. Problems were encountered with ventilation, loose rocks and wet rails, which caused trains to stall. 23. "It's so hard to fight because there are so many steep grades and loose rocks . 24. The loose rocks at the base of the wall form what are called scree slopes. 25. Kettle holes can also occur in ridge shaped deposits of loose rock fragments called till. 26. On Feb . 6, the party climbs to high camp through loose rocks , snow and ice. 27. "Some of the loose rock could have been cleaned out, " with more volunteers, Burdette said. 28. It consisted of bedrock ledges and loose rock . 29. Up to now, scientists have had close looks only at loose rocks on the Martian surface. 30. He stepped on a loose rock and slid.
