鄂尔多斯盆地东缘长7、长8油层组波痕特征及意义

Characteristics and Geological Significances for Ripple Marks from the Yanchang Formation in the East Margin of Ordos Basin

通过野外地质调查，在盆地东缘延河剖面长81油层和长72油层中发现了近南北向的波痕。其中，长81油层的波痕波脊走向335～350°，迁移方向与单向优势明显，陡坡倾向朝西，为流水波痕，反映了自东向西的流向，可能指示来自湖盆东部的物源；长72油层的波痕为峰尖谷圆，对称的浪成波痕，根据其参数计算。该点的湖盆水深在8～8．99m之间。

Based on the detailed field investigation,ripples,whose ridges were oriented NS,was found within Chang 81 and Chang 72 Reservoirs in Yanhe Section which was located on the east margin of Ordos Basin,of which the ripples in Chang 81 Reservoir was at 335~350°,it had obvious advantage of one-way migration,the trend of steep slope was toward the west,it was the ripple of water flowing,it indicated that the flow direction was from the east to the west.It possibly presented that the provenance is from the east of lake basin,the ripples in the Chang 7Reservoir was characterized by sharp crest and smooth vellay with symmetrical wave ripples.Based on the parameter calculation,it indicates that the water depth of the observed point is between 8~8.99 m.