论文部分内容阅读
由火山爆发产生的火山弹,在空间上虽然分布局限,然而却是研究火山机构和火山作用的重要依据。一般认为它是基性、中基性粘度较小的岩浆被喷至空中、旋转坠落凝固而成。多呈梨形、纺锤形和麻花状等旋扭形态。对于N_2O、SiO_2含量高、因而具有高粘度的流纹质熔浆能否形成火山弹,不少学者持怀疑甚至否定意见。文献中亦很少报导。我们在粤东某火山岩区发现,在流纹质火山岩中常常发育数量众多的火山球。外貌以球状和球状集合体为
Volcanic bombs emanated from volcanic eruptions, although spatially distributed, are an important basis for studying volcanic structures and volcanism. It is generally believed that it is basic, medium-based viscosity of the magma is sprayed into the air, rotating fall solidified. Mostly pear-shaped, spindles and twist twist shape. For N_2O, SiO_2 content is high, so with high viscosity of rhyolitic melts can form a volcanic bomb, many scholars suspect or even negative opinion. It is seldom reported in the literature. We found in a volcanic area of eastern Guangdong that a large number of volcanic spheres are often developed in rhyolitic volcanic rocks. Appearance with spherical and spherical aggregates for