New evidence of regressing and transgressing Jurassic siliciclastic coastlines within the Dhruma Formation in Northern Central Arabia, Saudi Arabia

The Middle Jurassic Dhruma carbonates have long been identified as a major hydrocarbon reservoir with massive proven reserves in Saudi Arabia and other Arabian Gulf countries. Regional studies indicate that these hydrocarbon-rich carbonates are replaced laterally by siliciclastic deposits in northern and southern central Arabia. However, none of those studies have clarified how these siliciclastic deposits were formed or how they can be correlated with their carbonate counterparts.