paleocurrent direction造句

• Based on the direction of sources and the ratios of sandstone to formation of sedimentary rocks , together with the sedimentary structures and textures , paleocurrent direction and the characteristics of paleontology , etc . , the planimetric maps of sedimentary facies of each stages in the studied area are compiled in order to recognized the extension of dominant facies and the evlotionary history of sedimentary environment , hi the stage of benxi and taiyuan , lagoon - tidal flat sediments are widespread in the area , and the deposits of estuary , lagoon and small delta in the northwest margin of ordos
  以物源方向和沉积岩砂地比值为基础，结合沉积结构构造、古水流方向及古生物特征等，编制了研究区各期次的沉积相平面图，以识别优势相展布和沉积环境演化。本溪期和太原期研究区泻湖?潮坪沉积分布广泛，西北缘发育河口湾、泻湖及小型三角洲沉积。
• Ascertaining the paleocurrent direction of the mesozoic basin and reconstructing the paleogeography ; ( 4 ) . deciding the material components and original structure sequences of the basin provenance , and coupling relationship between the sediments of the basin and geologic units of the provenance ; ( 6 ) . establishing the mesozoic tectonic evolution history of the dabie orogenic belt and discussing the collisional mechanism of the belt
  主要研究内容包括：厘定大别山北缘地区中生代地层的年代格架；划分岩相，确立沉积体系；确定中生代盆地古流向，恢复盆地的古地理；确定物源区物质组成、演绎物源区原始构造层序、建立盆地沉积物与物源区地质单元的耦合关系；根据沉积学以及区域地质研究，重塑大别山中生代构造演化历史，探讨大别山造山带的碰撞成因机制。