Basically speaking, the market has been controlled by Schlumberger, Halliburton Log Services Inc. and Baker Hughes Inc. Their logging markets have mainly centred in oilfields of North America.

• 国际测井市场基本被斯伦贝谢、贝克休斯、哈里伯顿三大服务公司垄断 ,且其市场主要集中在北美地区 ;