The total costs of oilfield exploration can be divided, according to exploratory area, contract method, and the type of well, into simple groups in order to evaluate separately the influence of drilling footage and average unit cost on the total costs.

• 在研究勘探总成本的变动中，可以按区块、包方式和井别进行简单分组，分别研究钻井进尺和平均成本对勘探总成本的影响。