China Oilfield Services Ltd is a China-based company primarily engaged in providing integrated oilfield services. The Company operates primarily through four business segments. The Drilling Services segment mainly provides oilfield drilling services. The Oilfield Technical Services segment provides oil and gas well testing and downhole services, including drilling fluids, directional drilling, cementing and completion, sales of oilfield chemicals and well repair, as well as seismic data processing services. The Marine Services segment is engaged in the transportation of materials, supplies and personnel to offshore facilities, and the movement and placement of drilling structures. The Geophysical Exploration and Engineering Survey Services segment is engaged in offshore seismic data acquisition and marine surveying services. The Company mainly operates its businesses in domestic and overseas markets.