A total of 362 marine core samples from 200 meters below the sea-floor (mbsf) were examined through the International Ocean Drilling Program (IODP), Hole U1325B, Northern Cascadia Margin. The diversity parameters increased at ~200 mbsf during the Early Middle Pleistocene Transition (EMPT) period and gradually decreased towards ~165 mbsf. The diversity pattern is also notable, which projects the termination of EMPT due to increased orbital cyclicity (~41,000 to ~100,000 years). The δ¹⁸O (Uvigerina peregrina) at regular intervals ~150 mbsf, ~110 mbsf, ~50 mbsf and ~20 mbsf certainly agrees with the abundance of Cibicides wuellerstorfi, indicating the intrusion of California Cold Current in the region. The relative abundance rate of Cassidulina laevigata inversely proportional to the peaks of C. wuellerstorfi strongly indicating the circulation of Alaskan warm current in the Cascadia Margin. The paleoproductivity and oxygenation proxies strongly suggest the maximum primary productivity throughout ~85 mbsf towards the recent interval and the study region are showing oxic to suboxic environment further, the correlation matrix and the principal component phenomenon also strongly mirror the relationship and driving factors of the paleoceanographic condition. The present study aimed to understand the connections between each proxy liable to the paleoceanographic and paleoproductivity changes during the Early-Middle Pleistocene, Northern Cascadia Margin.

通过国际大洋钻探计划 (IODP)，U1325B 孔，北卡斯卡迪亚边缘，对来自海底以下 200 米 (mbsf) 的总共 362 个海洋岩心样本进行了检查。在早中更新世过渡（EMPT）期间，多样性参数在~200 mbsf 处增加，并逐渐降低至~165 mbsf。多样性模式也很显着，它预测 EMPT 由于轨道周期增加（~41,000 到 ~100,000 年）而终止。δ ¹⁸ O ( Uvigerina peregrina ) 以固定间隔~150 mbsf、~110 mbsf、~50 mbsf 和~20 mbsf 当然与Cibicides wuellerstorfi的丰度一致，表明加州寒流侵入该地区。相对丰度Cassidulina laevigata与C. wuellerstorfi的峰值成反比，强烈表明阿拉斯加暖流在卡斯卡迪亚边缘的环流。古生产力和氧化指标强烈表明，在最近的区间内~85 mbsf 的最大初级生产力，研究区域进一步显示出有氧到低氧环境，相关矩阵和主成分现象也强烈反映了古海洋学的关系和驱动因素状况。本研究旨在了解在早中更新世，北卡斯卡迪亚边缘，每个可能受古海洋学和古生产力变化影响的代理之间的联系。