Tertiary sediment cores and microfossils from the Pacific Ocean floor
Tertiary sediment cores and microfossils from the Pacific Ocean floor
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太平洋海底的第三纪沉积物岩心和微化石
DOI：
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发表时间：
1964
期刊：
影响因子：
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通讯作者：
B. Funnell
中科院分区：
文献类型：
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作者：
W. Riedel;B. Funnell
从1950年至1961年初斯克里普斯海洋学研究所收集的大约900个太平洋深海岩心中，选择了含有第三纪沉积物或大量经过改造的第三纪微化石的5个岩心进行描述。85个核所覆盖的区域从北纬45°到南纬45°，从东经151°到西经73°，尽管大多数是在热带地区收集的。对每个岩心进行了简短的岩性和微古生物学描述；尽可能提供岩心的照片和邻近地形的剖面图。研究了放射虫、浮游有孔虫和钙质纳米浮游生物。地层解释是基于这三个类群，并以放射虫和有孔虫的物种表为依据。年龄范围从始新世到上新世，其中一个地方有白垩纪的改造。对第三纪太平洋中上层沉积物和水团的分布提出了初步的解释。中新世和上新世的沉积物在大多数地方与附近的第四纪沉积物相似，并得出近地表水流和水团与今天的大致相似的结论。唯一明显的例外是赤道流系统的北边界在139°w向北移动了约5°，亚北极流的南边界在173°w可能向南移动了5°。渐新世期间，赤道流系统的北边界明显比现在的位置（137°w）偏北7°。在西经130-50°，该洋流系统的南部边界和西风流的北部边缘似乎位于它们目前的位置附近。始新世产状与第四纪沉积物类型有较大的偏离。赤道流系统的北边界似乎位于其目前位置的北9°，在西经135-65°。这个时代在赤道以南发生的少数事件，不能轻易地用类似于今天的水团模式来解释。岩心的证据表明，在第三纪期间，碳酸钙补偿深度没有明显降低，但在东北太平洋低纬度地区，在渐新世期间，碳酸钙补偿深度可能下降到5100m。到目前为止，尚未发现地形与第三系露出或浅埋沉积物的位置之间的系统关系。
Tighty-five cores containing either Tertiary sediment or abundant reworked Tertiary micro-fossils have been selected for description from approximately 900 Pacific deep-sea cores collected by the Scripps Institution of Oceanography between 1950 and early 1961. The area covered by the 85 cores extends from about 45°n to 45°s, and from 151°e to 73°w, although most were collected within the tropics. A brief lithological and micropalaeontological description is given for each core; wherever possible, a photograph of the core and a profile of the adjacent topography are provided. The Radiolaria, planktonic Foraminifera, and calcareous nannoplankton were investigated. Stratigraphical interpretations are based on all three groups and supported by lists of species of Radiolaria and Foraminifera. The ages range from Eocene to Pliocene, with reworked Cretaceous at one locality. Tentative interpretations are put forward regarding the distribution of pelagic sediments and water masses in the Pacific during the Tertiary. Miocene and Pliocene sediments are similar at most localities to near-by Quaternary deposits, and it is concluded that near-surface currents and water masses were generally similar to those of the present day. The only apparent exceptions are a displacement of the northern boundary of the Equatorial Current System to a location about 5° north of its present position at 139°w, and possibly a 5° southward displacement of the southern boundary of the Subarctic Current at 173°w. During the Oligocene, the northern boundary of the Equatorial Current System was apparently 7° north of its present position at 137°w. At 130–50°w, the southern boundary of that current system and the northern edge of the West Wind Drift appear to have been situated near their present positions. Eocene occurrences show greater departures from the pattern of Quaternary sediment types. The northern boundary of the Equatorial Current System appears to have been situated about 9° north of its present position, at 135–65°w. The few occurrences of this age south of the Equator cannot readily be interpreted in terms of a pattern of water masses similar to that of the present day. The evidence from the cores does not indicate any substantial lowering of the calcium carbonate compensation depth during the Tertiary, with the exception that in low latitudes in the north-east Pacific it may have been depressed to 5100m during the Oligocene. No systematic relationship between topography and the localities of Tertiary sediments cropping out or shallowly buried has so far been worked out.