Answer:
The outer core is more dense
Lava flows are the least hazardous of all processes in volcanic eruptions. How far a lava flow travels depends on the flows temperature, silica content, extrusion rate, and slope of the land. A cold lava flow will not travel far and neither will one that has a high silica content. Such a flow would have a high viscosity<span> (a high resistance to flow). A basalt flow like those in Hawai'i have low silica contents and low viscosities so they can flow long distances. Such a flow can move as far away as 4 km from its source and have a thickness of 10 m (Bryant, 1991). These flows can move at rates of several kilometers per hour (Scott, 1989). </span><span>More silica-rich flows can move as far away as 1.3 km from their sources and have thicknesses of 100 m (Bryant, 1991). These flows can move at rates of a few to hundreds of meters per hour (Scott, 1989). If a lava flow is channelized or travels underground in a lava tube then the distance it travels is greatly extended.</span>
For much of the last quarter century, the leading theory of the driving force behind tectonic plate motions envisaged large scale convection currents in the upper mantle, which can be transmitted through the asthenosphere.
Answer:
Exposed
Explanation:
When the ice age ended, the glaciers slowly retreated until they reached their current extent limited to the polar regions and alpine mountain climates. The land covered by ice had also been depressed by the weight of the massive glaciers and consequently began to rebound in the centuries following the retreat of the ice sheets. These once frozen lands also turned into large boreal forests with rich ecosystems.
