Sinopec Oilfield Service Corp is a China-based company engaged in the provision of integrated oil and gas engineering and technical services. The Company operates five segments. The Geophysics segment engages in providing terrestrial and marine geophysical exploration, development and technical services. The Drilling Engineering segment engages in providing land and ocean drilling design, construction, technical services and drilling instrumentation. The Logging and Mud Logging segment engages in providing land and ocean project contracting and technical services for collection, monitoring, transmission, processing and interpretation and evaluation of wellbore oil and gas, geology and engineering information. The Special Downhole Operations segment engages in providing oil engineering technical and construction. The Engineering Construction segment provides feasibility studies, design, procurement, construction for projects of onshore and offshore oil and gas fields and others.