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对北大西洋东北爱尔兰西南陆架和斜坡PorcupineSeabight海区综合大洋钻探307航次1317E井灰泥杂基样品的生物硅和碳酸钙含量、1318B井全岩样品的生物硅含量进行了测量,在减除珊瑚文石质骨屑、同生白云石、岩屑高镁方解石基础上估算了第四纪原始生产力.结果显示,原始生产力与世界其他地区同期相比均较高(一般10～30gcm-2ky-1),存在明显的旋回性变化,与δ13C值变化呈镜像负相关.进一步研究表明,较高的原始生产力可能与温暖的北大西洋东北中心流(ENAW)和陆棚边界流(SEC)有关,其与δ13C值镜像相关则可能受控于北大西洋深部冷水团和/或地中海暖水团侵入,而生产力快速增加-减少旋回周期可能与米兰科维奇的斜率轨道应力有联系.分析还发现,冷水碳酸盐泥丘的发育与表层海水原始生产力具有正相关性,暗示高的原始生产力会促进冷水碳酸盐泥丘的生长,但不一定是碳酸盐泥丘形成的必要条件.进而提出,研究区碳酸盐泥丘中的远洋灰泥杂基记录了北大西洋东北表层海水生产力变化信息.
The biogenic silicon and calcium carbonate contents of the stucco samples of well No. 1317E and the whole rock sample of the 1318B well were measured for the North Atlantic Ocean in the North China Shelf and the slope of the Porcupine Seabight Sea Area, The original productivity of Quaternary was estimated on the basis of calcareous, dolomitic dolomite, dolomitic dolomite and cuttings high-Mg calcite. The results showed that the original productivity was higher than that of the rest of the world (10 ~ 30gcm-2ky-1 in general) There is a clear cyclical change with a negative correlation with the change of δ13C value.Further studies show that the higher initial productivity may be related to the warm northeastern North Atlantic flow (ENAW) and the continental shelf boundary flow (SEC), and δ13C The value-mirror correlation may be controlled by the intrusion of deep cold water mass and / or warm Mediterranean mass in the North Atlantic, and the rapid increase of productivity - the reduction of the cyclotron may be related to the slope orbit stress of Milankovitch. The development of salt mounds is positively correlated with the initial productivity of surface seawater, suggesting that high initial productivity will promote the growth of cold-water carbonate mounds, but not necessarily carbon Necessary conditions of salt mound formed. Further proposed carbonate mound ocean research area stucco heteroaryl group has registered the change in Northeast Atlantic surface waters productivity information.