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古地理分析方法火山岩岩层火山岩岩层可划分成两个古地理单位:(1)水下熔岩平原,(2)中央火山杂岩。上述两个单位是经过大片火山岩相的详细填图而确定的。本文拟讨论鉴别和了解其内部构造的几个实例。水下熔岩平原水下熔岩平原属拉斑玄武岩或科马提岩流的单一层序,其中无法认出重要的火山活动中心。因而,由近处至远处,从块状玄武岩到枕状玄武岩的过渡现象是杂乱无章的。流纹岩流和穹窿少见,而且也显示随意分布。岩组可追索达100公里以上。较小地层单位(岩流和岩流群)也可追索到相当远的距离。所以亚单位具平板状。阿比提比湖东南的金诺耶维斯群将作为实例来叙述。
Paleogeographic analysis Volcanic rock volcanic rock strata can be divided into two paleogeographic units: (1) underwater lava plains, (2) central volcanic complexes. The above two units were determined by detailed mapping of large volcanic facies. This article discusses several examples of identifying and understanding its internal structure. Underwater Lava Plains The underwater lava plains are a single sequence of tholeiitic basalt or komatiite rocks, where important volcanic activity centers can not be identified. Thus, from near to far, the transition from massive basalt to pillow-shaped basalt is disorganized. Rhyolite streams and domes are rare, but also show random distribution. Rock group can recover up to 100 kilometers. Smaller stratigraphic units (rock and rock mass) can also be retrieved to considerable distances. So sub-unit with flat. Jinnuowei Si southeastern Abidjan will be described as an example.