question: What materials are underpinning the land surface of Houston ?
answer: unconsolidated clays , clay shales , and poorly cemented sands
turker_answer: Unconsolidated clays , clay shales , and poorly cemented sands are underpinning the land surface of Houston .
rule-based: Unconsolidated clays , clay shales , and poorly cemented sands are underpinning the land surface of Houston .