Gulfsands Petroleum PLC has plugged and abandoned the Wardieh-1 exploratory well 16 km southeast of Yousefieh field in Syria Block 26 after it encountered a zone of live asphaltic hydrocarbons overlying a porous reservoir, the combination of which threatened the safety of the drilling operation.
The well found the asphalt zone in a layer overlying and within the upper part of the exploration objective in the Cretaceous Shiranish and Massive formations. Gulfsands ran logs and deployed a high-density, oil-based drilling fluid in place of the water-based system to assist with the control of influxes of asphalt and maintain borehole stability.
Upon drilling ahead, the well encountered a highly porous and potentially cavernous zone resulting in the complete loss of the heavier drilling fluid, which resulted in the decision to halt operations for safety reasons. TD is 2,229 m, 271 m short of planned TD.
The Wardieh-1 well was designed as a test of a combined structural and stratigraphic trap in formations of Cretaceous age. It targeted a new stratigraphic exploration play.
The exploration objectives in the Wardieh area remain of interest due to the presence of live asphaltic hydrocarbons and underlying highly porous reservoir rocks, Gulfsands said. A similar occurrence of a hazardous asphaltic zone overlying a productive oil field of Cretaceous age is found at North Karatchok field 25 km northeast.
The company will conduct a comprehensive geological and operational review of the Wardieh-1 well result before deciding whether to drill again and will establish safe procedures.