The deepest relief along the bar is on the shoreward side where it is backed up by a lagoonal channel . 砂洲上最陡峻的地形位于泻湖水道积滞处的向滨一侧。
2.
In the jurassic and cretaceous , generally it was also the shelf sea ( shallow sea ) , but there were lacustrine and lagoonal environments in different parts of the basin 侏罗纪白垩纪在总的浅海陆棚环境下，盆地不同地区也形成了湖泊和?湖环境。
3.
( 2 ) based on the two important sections of yanshiping and yicangma , a study is conducted on the sedimentary features and facies of middle - upper jurassic series , it is suggested that quemo formation is river - delta facies deposit , buqu formation is chiefly carbonate ramp facies deposit , xiali formation is delta - tidal flat facies deposit , ? suowa formation is mixed shelf - lagoonal facies deposits and xueshan formation is river - delta facies deposit ( 2 )以雁石坪和依仓玛两条重点剖面为基础，开展了中?上侏罗统沉积特征、沉积相等方面研究，认为研究区雀莫错组为河流?三角洲相沉积，布曲组以碳酸盐缓坡相沉积为主，夏里组为三角洲?潮坪相沉积，索瓦组为混积陆棚?泻湖相沉积，雪山组为河流?三角洲相沉积。
