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基于一些业已报道的中国Kungurian期至Roadian期界线附近的菊石材料(26个属,48个种),对其进行壳的形态空间分析,发现空谷期菊石在形态空间上主要分为三个类型:1)旋环重叠程度D=0—0.1,旋环膨胀速率W=1.5—2.5,代表Saunders等(2004)的A类型;2)D=0—0.1,W=3,代表F类型;3)D=0.05—0.15,W=4—5,与F类型相比较,具有较大膨胀速率。相对应的罗德期菊石主要可以分为两个类型:1)D=0.1—0.25,W=1—2,代表A类型;2)D=0.4—0.6,W=1—2,代表C类型。从壳的形态发育史来看,空谷期到罗德期总体趋势是连续的,并没有受到外界大的干扰,同时也发生了明显的变化(罗德期形态空间明显占据了更广阔的位置,代表了菊石演化的新方向),壳不仅变得更加外卷,壳的膨胀速率也有所减小,比如,空谷期存在的膨胀速率较大的第三种类型在罗德期中并未发现。这一趋势在全球早—中二叠世菊石壳D-W等密度图中同样反映出来,说明尽管空谷期—罗德期这一时间段我国存在较多地方性属种(以其特殊的壳饰与缝合线为特征),在国际对比中难以应用,但是从壳的形态发育特征来说,与其它地区对比具有潜在的意义。
Based on the morphological and spatial analysis of some of the previously reported ammonoid materials (26 genera and 48 species) near the Kungurian-to-Roadian boundary in China, it was found that there are mainly three types of emphysema in the morphological space Type: 1) The degree of cyclical overlap D = 0-0.1, the swirl ring expansion rate W = 1.5-2.5, representing type A of Saunders et al. (2004); 2) D = 0-0.1 and W = 3) D = 0.05-0.15, W = 4-5, with a larger expansion rate than the F type. The corresponding Rhodochrosite mainly can be divided into two types: 1) D = 0.1-0.25, W = 1-2, representing A type; 2) D = 0.4-0.6, W = 1-2, representing C Types of. From the morphological development history of the shell, the overall trend from Holocene to Rhode Island is continuous without major interference from the outside world, and obvious changes have also taken place at the same time (the Rhodian morphological space obviously occupies a broader position, Representing a new direction for the evolution of amethyst), the shell not only becomes more overturned, but also the rate of expansion of the shell is also reduced. For example, the third type with a larger expansion rate in the valley period was not found in the Rohde. This trend is also reflected in the DW density maps of the global early-middle Permian ammonoid crust, indicating that although there are more endemic genera in our country during the Holocene-Rhode Island period And sutures) are difficult to apply in international comparisons, but are potentially relevant to other regions in terms of morphological characteristics of the shell.