Galileo at Io: results from high-resolution imaging.
Galileo at Io: results from high-resolution imaging.
复制标题
伽利略在木卫一：高分辨率成像的结果。
作者：
A. McEwen;M. Belton;H. Breneman;S. Fagents;P. Geissler;R. Greeley;James W. Head;G. Hoppa;W. Jaeger;Torrence V. Johnson;L. Keszthelyi;K. Klaasen;R. Lopes;K. Magee;M. Milazzo;Jeffrey M. Moore;R. Pappalardo;Cynthia B. Phillips;J. Radebaugh;Gerald Schubert;P. Schuster;D. Simonelli;R. Sullivan;P. Thomas;E. Turtle;David A. Williams
1999 年末/2000 年初，伽利略号航天器上的固态成像实验返回了 100 多张火山活动木卫一的高分辨率（每像素 5 至 500 米）图像。我们观察到了活跃的熔岩湖、活跃的熔岩幕、活跃的熔岩流、破火山口、山脉、高原和平原。一些富含二氧化硫的羽流是从远端流喷发的，而不是从硅酸盐熔岩的源头（火山口或裂缝，通常有红色火山碎屑沉积物）喷发的。赤道地区的大部分活跃流正在绝缘地壳下缓慢就位，但在所有纬度也发现快速就位的渠道化流。没有证据表明存在高粘度熔岩，但一些明亮的熔岩流可能由硫而不是镁铁质硅酸盐组成。山脉、高原和破火山口受到构造和重力塌陷的强烈影响。侵蚀的河道和陡坡表明，上部约 1 公里的许多部分都富含挥发物。
During late 1999/early 2000, the solid state imaging experiment on the Galileo spacecraft returned more than 100 high-resolution (5 to 500 meters per pixel) images of volcanically active Io. We observed an active lava lake, an active curtain of lava, active lava flows, calderas, mountains, plateaus, and plains. Several of the sulfur dioxide-rich plumes are erupting from distal flows, rather than from the source of silicate lava (caldera or fissure, often with red pyroclastic deposits). Most of the active flows in equatorial regions are being emplaced slowly beneath insulated crust, but rapidly emplaced channelized flows are also found at all latitudes. There is no evidence for high-viscosity lava, but some bright flows may consist of sulfur rather than mafic silicates. The mountains, plateaus, and calderas are strongly influenced by tectonics and gravitational collapse. Sapping channels and scarps suggest that many portions of the upper approximately 1 kilometer are rich in volatiles.