Sinopec Oilfield Service Corporation provides petroleum engineering and technology services. It operates through six segments: Geophysics, Drilling Engineering, Logging and Mud Logging, Special Down-Hole Operations, Engineering Construction, and Others. The Geophysics segment offers terrestrial and marine geophysical exploration, development, and technical services. The Drilling Engineering segment provides land and ocean drilling design, construction, and technical services, as well as drilling instrumentation. The Logging and Mud Logging segment offers land and ocean project contracting and technical services for collection, monitoring, transmission, and processing and interpretation, as well as engages in the evaluation of wellbore oil and gas, geology, and engineering information. The Special Down-Hole Operations segment provides oil engineering technical and construction services, including oil testing, well repair, and lateral drilling, as well as fracturing, acidizing, and oil assignments. The Engineering Construction segment engages in the provision of various services, such as feasibility studies; design, procurement, and construction services for onshore and offshore oil and gas fields, long-distance pipeline projects, oil and gas transporting process projects, storage and transportation projects, petrochemical supporting projects, LNG projects, building construction, water resources and hydropower, ports and waterways, electricity transmission, and distribution projects; manufacturing of pressure vessels; and coal chemical engineering, geothermal utilization, energy saving, and municipal roads and bridges. The company was formerly known as Sinopec Yizheng Chemical Fibre Company Limited and changed its name to Sinopec Oilfield Service Corporation in March 2015. The company is headquartered in Beijing, the People's Republic of China. Sinopec Oilfield Service Corporation is a subsidiary of China Petrochemical Corporation.