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Summary
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| Current Update | Update Archive | |
7 February 2002
Changes in hornitos at 2300 feet
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| Left. Sulfur encrustations have grown since January 31 on the hornitos at the 2300-foot elevation, and the middle hornito has collapsed, leaving a gap like a missing front tooth. A narrow spire tops the western (left) hornito. Right. Pu`u `O`o is visible through the gap. Note the stump of the collapsed hornito. | |
8 February 2002
Lava flows at a rootless shield
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Aerial view of a flow being erupted from one of the rootless shields active above the main lava tube downslope form Pu`u `O`o. Width of view is 75-100 m. The shiny crust indicates that it is very hot. A rootless shield is a pile of lava flows built over a lava tube rather than over a conduit feeding magma from within the earth. Rootless shields along the tube system commonly have a flat top containing a shallow lava pond. |
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| Two views on the ground of a crusted flow moving away from a rootless shield. This kind of moving flow is often called slabby pahoehoe, though the term pahoehoe should be reserved for the solidified flow only. | |
15 February 2002
Chain of rootless shields
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Looking northwestward along a chain of six rootless shields toward Pu`u `O`o, the source of fume in upper center. The shields are fed by lava flowing from Pu`u `O`o through a tube system that extends beneath the shields to the lower part of the photo. Shield in foreground is the lowest of six and is centered at about the 2050-foot elevation. Uppermost shield--indistinct in this view--is centered at about the 2240-foot elevation. Active or recently active lava can be recognized by its shiny silvery appearance. Four of the shields were active today. |
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21 February 2002
Breached perched pond on rootless shield
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| The perched pond atop the rootless shield at 2150 feet--the middle shield in February 15 photo--breached on February 18. Since then, lava has been spilling out of the pond through the breach, forming an `a`a flow now 2 km long. Left, aerial view showing the dark `a`a down slope from the broken side of the pond. Right, aerial view looking across the long axis of the pond through the breach. The active perched pond is mostly crusted, but faint incandescence and lineations in crust show that lava is flowing away from observer. | |
23 February 2002
River of lava leaving rootless shield at 2150 feet
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| Left: Lava flow leaves perched pond on top of rootless shield (left part of image) and flows southwestward (right) as a channeled river several meters wide. Right: River branches into two arms, the larger--the upper in the image--plunging down a cascade above which blue sulfurous fume hangs. Lava flows from right to left. The branch is also shown at the far right side of the left image. | |
Surge from front of `a`a flow below rootless shield at 2150-foot elevation
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Series of four images taken in early morning sun showing surging advance of front of an `a`a flow, a distributary of the branch of the cascading river shown in right image above. This image taken at 07:12:14. |
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07:12:40. Twenty-six seconds later, note how the large solid chunk of crust has tumbled downward, rotated, and broken into two large pieces. |
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07:12:50. Ten seconds later, flow is flattening out and grinding away the edges of the large piece of crust. Shadow of photographer gives scale. |
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07:13:12. Twenty-two seconds later and from a slightly different vantage point, the surge from the flow front is ending, and the new lobe is spreading out and slowing. |
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| Maps of lava-flow field, Kilauea Volcano |
Map of flows from Pu`u `O`o: 25 February 2002
Map shows lava flows erupted during the 1983-present activity of Pu`u `O`o and Kupaianaha (see large map). The flows in January and February 2002 are shown in dark red; they were fed by several rootless shields located directly above the lava tube at elevations between 2,200 and 2,050 feet. In addition, narrow streams of lava, mainly within tubes, have been descending Pulama pali along the west side of the Dec. 2000-Jan. 2002 flow field; this lava, which comes from a breakout just above the pali, is heading for the 1999 shatter ring. The most recent ocean entries at East Kupapa`u and Kamoamoa stopped in mid January and late January respectively.
Most of the recent flows between December 2000 and December 2002 were fed from breakout points at 2300-1700 feet, above the Pulama pali.
Eruption-viewing opportunities change constantly, so refer to this page often. Those readers planning a visit to Kilauea or Mauna Loa volcanoes can get much useful information from Hawai`i Volcanoes National Park; be sure to click on the IN-DEPTH button.
Contact: hvowebmaster@usgs.gov
Updated: 10 March 2002 (DAS)