Publication Date:
2006-04-06
Description:
A model for the radiative cooling of thermally well mixed lava flows is presented and the relationship between effusion rate and length and area is analyzed. If radiative cooling is the prime mode of heat loss for a lava flow, one should expect to see a stronger correlation between the effusion rate and the plan area of the flow, than between effusion rate and just flow length. Different flows on a single volcano with differing initial temperatures, volatile content, and gross compositions should yield different areas for a given effusion rate. Likewise, a range of slopes for the relationship between effusion rate and flow area should result from comparisons between different volcanoes. As a test of these ideas, available data on the effusion rates, lengths, and areas of Hawaiian and Etnean flow is studied. It was found that: (1) the effusion rate/area correlation was statistically more significant than the correlation between effusion rate and length for four out of the five eruption episodes which met the necessary criteria of more than three individual flows with area, length, and effusion rate independently measured; (2) that there exists a minimum length and area for a given effusion rate, reflecting competition between overall characteristic proportionality between effusion rate and flow length, width, and area.
Keywords:
GEOPHYSICS
Type:
NASA. Washington Rept. of Planetary Geol. Program, 1983; p 141-143
Format:
text
