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>
The answer is 4. You round up one number when the decimal point is equal to or more than .5
NOAA's Office for Coastal Management maintains a detailed online interactive mapping tool called Historical Hurricane Tracks at www.coast.noaa.gov/hurricanes. This tool offers users the ability to search and display global tropical cyclone data. The information can also be downloaded in widely-used GIS data formats.
Satellites, reconnaissance aircraft, Ships, buoys, radar, and other land-based platforms are important tools used in hurricane tracking and prediction. While a tropical cyclone is over the open ocean, remote measurements of the storm's intensity and track are made primarily via satellites.
In geology subduction is the process whereby one tectonic plate is forced underneath another tectonic plate along a convergent boundary. Places where this type of plate interaction occurs are called subduction zones. Subduction zones have a high rate of volcanism, earthquakes, and mountain building.
True if the map shows a scale.
