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羌塘盆地侏罗纪末至早白垩世地层包括扎窝茸组、雪山组、白龙冰河组和索瓦组上段,目前对它们的划分、对比和相互间关系的认识不一。笔者根据各组的含义和时代依据,指出各地层组为岩石地层单元,目前资料尚不足以作进一步年代学划分。通过全面统计各组的分布情况,分析各组的沉积特征,发现白龙冰河组为陆棚相,仅见于盆地北西部;索瓦组上段为海湾泻湖相,见于盆地中部;雪山组和扎窝茸组为河流—三角洲相,见于北东部。为此,认为各地层组是盆地内同期异相沉积,作为上下关系处理是不妥的,据此又提出了新的地层对比方案,认为盆内最高海相层位应该跨入了下白垩统,海水最终是向北西方向逐步退出盆地的。
The Late Jurassic to Early Cretaceous strata in the Qiangtang Basin, including the Zhanerong Formation, the Xueshan Formation, the Bai Long Bing He Formation and the Upper Surawa Formation, differ in understanding of their division, contrast and mutual relations. According to the meaning of each group and the basis of the times, the author points out that the strata are lithostratigraphic units, and the current data are not enough to make further geochronological division. By comprehensively analyzing the distribution of each group and analyzing the sedimentary characteristics of each group, it was found that the Bailongbahe Group is continental shelf facies, which is only found in the northwestern part of the basin; the upper part of the Suowa Group is the Gulf Lagoon facies, which is found in the middle of the basin; Velvet group for the river - delta phase, seen in the north east. Therefore, considering that the stratigraphic groups are heterogeneous sediments in the same period of the basin, it is not proper to deal with the up-and-down relationship. Therefore, a new stratigraphic correlation scheme is proposed, in which the highest marine strata in the basin should cross into the Lower Cretaceous , The sea water is eventually gradually withdrawn from the basin to the north west.