| Current Update | Update Archive |

21 March 2002

Pu`u `O`o's crater and rootless shield at 2247 feet

West view of crater of Pu`u `O`o, showing new fill of lava erupted in past couple of weeks. The new lava is mostly crusted over. Small incandescent vents are visible near the east and southeast ends of the crater. The eastern vent is the spatter cone at the East Pond Vent (see image on March 8).

| med | large |

| med | large |	| med | large |	| med | large |
New shield at 2247-foot elevation. Left. Perched pond on the shield, actively spilling lava southeastward, toward top of Pulama pali (in distant background). Center. View looking up a channeled pahoehoe and slabby pahoehoe flow toward the 2247 rootless shield (top of photo). Note the typical braided and anastomosing character of the flow. Right. Another upslope view of the channeled pahoehoe, better showing the perched pond at 2247 feet and the slope of Pu`u `O`o in background.

Maps of lava-flow field, Kilauea Volcano

28 March 2002

Pu`u `O`o spatter cones, spitting hornito, and rootless shield

Aerial view looking west across floor of Pu`u `O`o's crater. Three spatter cones can be seen. East Pond Vent is in lower left, a remarkable, vertically walled chimney is in the center, and the Beehive cone is partly obscured by fume in background. Shiny crust at Beehive is actively moving lava. Each cone is 7-10 m high.

| med | large |

| med | large |	| med | large |
Views outside Pu`u `O`o. Left. Spatter bursting from spirelike hornito at the 2300-foot elevation. The bursts lasted a second, as large bubbles broke. Two or three bursts, in rapid succession, would follow a period of 5-10 seconds of inactivity.  Right. Lava flowing from perched pond (top) through breach in levee and then across an older shield.

29 March 2002

Spatter structures, and crustal overturning in Episode 55 crater

| med | large |	| med | large |
Two different structures built of spatter Left. Remarkable, 11.8-m-high spire at one of the hornitos at the 2300-foot elevation, between Pu`u `O`o and the rootless shields. Note person for scale. Right. Two flows spilling from January 02 vent, the middle of three spatter cones on the floor of Pu`u `O`o's crater. This cone is 9.3 m high. Shiny crust is fresh and hot.

Crustal overturning in Episode 55 crater

Lava began to fill the Episode 55 crater, just west of Pu`u `O`o, on March 27-28. A pond formed, with a floating crust. Gas bubbles rising from the lava in the pond are trapped by the crust. A density inversion results; lighter, bubbly lava underlies denser crust. Eventually a crack forms in the crust. The lighter lava gushes to the surface and overrides the crust. A slab of the crust breaks off, turns on end, and dives into the pond like a sinking ship. This process is called crustal overturning. An overturning event often sweeps across the surface of a pond in a few tens of seconds. These photos show one such event, moving toward the camera.

The overturning has just started. The red line is the advancing front. Lava behind the front is crusting over and clearly hotter than the older crust nearer the camera.

| med | large |

The overturning is advancing across the long dimension of the 85-90-m-long, 25-30-m-wide crater.

| med | large |

Note a bit more fume in the crater. The rapid release of trapped gas as the crust overturns contributes to the fume.

| med | large |

In this view, the crust nearest the camera has just overturned, and the fresh lava has not yet developed new crust.

| med | large |

The crust has now been completely renewed by the overturning event. The radiant heat from such overturning is great--witness the observer protecting his face.

| med | large |

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.