Sandstorm by James Rollins

The glass enclosure exploded outwards. Stabbing spears pierced his left side. But he barely felt the cuts as a wave of blast-furnace heat struck him, searing, burning away all the oxygen. The next explosion ripped Harry from his feet and threw his body clear across the gallery. But only flaming bones hit the security gate, melting themselves into the steel grating... Lady Kara Kensingtons family paid a high price in money and blood to found the gallery that now lies in ruins. And her search for answers is about to lead her into a world she never imagined existed: a lost city, buried beneath the Arabian desert, where something astonishing is waiting... A covert government operative hunting down a traitor is being drawn there as well. But at the end of a perilous journey lies an ageless power that can create a utopia - or tear down everything humankind has built over millennia of civilisation...