论文部分内容阅读
本文是研究边缘海和活动边缘褶皱建造地区岛弧的深部构造与表面构造的地质问题。由于岩浆运移,故这里最为充分地呈现了可视为具有部分熔融区域的软流圈。预计在构造活动地区软流圈较厚。在岛弧之间盆地内以现代的拉斑玄武岩为特征。异常地幔直接伸至地壳。深水盆地地区的软流圈埋深由30km(Пapece-Beлa盆地)到60-80km。拉斑玄武岩的年龄为由中新世到第三纪,以至到晚白垩纪,在构造活动地区,以及岛弧,边缘海、年青的山脉—褶皱建造地带热流值高,而在太平洋深水盆地和大陆地盾地区则热流值低,故表明其内力作用的机制是不相同的。含软流圈在内的上地幔过程取决于过渡带中的内力作用。过渡带中软流圈的形成是以低密度物质为先决条件的,同时导致体积的增大,过剩体积的出现促使岩石圈上升和拉伸,形成边缘海和岛弧区的深水盆地。拉斑玄武岩沿断裂溢出,软流圈隆起的过程伴随着强烈的矿化作用。山间岛弧之间的盆地和岛弧背部的构造过程与通过大洋中脊的过程相似,在大洋中脊处发现具有锌、铜和铁的硫化物沉积层的热液现象。例如在北纬13°和21°附近的东太平洋轴部地区的胡安德福卡中脊。所以,在过渡带地区古老的古裂谷构造可能是有用矿产的远景地区。
This article is a study of the geology of the deep tectonics and surface texture of island arcs in the marginal seas and active fold structures. Due to magmatic migration, the asthenosphere, which can be considered as having partially melted regions, is most fully presented here. It is estimated that the asthenosphere is thick in the tectonic activity area. Within the arc between the basins are modern tholeiitic basalts. Abnormal mantle extends directly to the crust. The asthenosphere in the deep-water basin is buried at a depth of 30km (from the basin of Пapece-Beлa) to 60-80km. The age of tholeigenic basalt is from Miocene to Tertiary, from the Late Cretaceous, in tectonic activity area, and the heat flow of the island arc, marginal sea, young mountain-fold zone is high, while in the Pacific deep-water basin and The mainland shield area is low heat flow, it shows that the mechanism of its internal force is not the same. The process of upper mantle including asthenosphere depends on the internal force in the transition zone. The formation of asthenosphere in the transitional zone is prerequisite for the formation of low-density materials and leads to the increase of volume. The emergence of excess volume causes the lithosphere to rise and stretch to form a deep-water basin with marginal sea and island arc. The tholeiite basalt along the fault spill, asthenospheric uplift process accompanied by a strong mineralization. The tectonic processes of basins and arc backs between mountain island arcs are similar to the processes of mid-ocean ridges, and the hydrothermal phenomena of sulphide deposits with zinc, copper and iron are found at mid-ocean ridges. Such as the Juan de Fuca Ridge in the eastern Pacific Axis region at latitudes 13 ° and 21 ° N. Latitude. Therefore, the ancient Paleogene structures in the transition zone may be a long-term prospect of useful minerals.