According to the relative amounts of DBTS and DDI vs DMI values of Tarim oils, the major source rocks in Tarim Basin are identified as the dark and black laminated micrite and marlite deposited in the Ordovician continental shelf zone.

• 根据DBTs的相对含量和DDI及DMI指标判识，表明塔里木盆地下古生界原油主要来自碳酸盐岩，奥陶系广海陆棚台地相喑色泥晶灰岩是主力油源岩。 这一认识将有助于确认主力油源区的分布，具有较大的勘探意义。