As more evidence about the large eruption at Lengai volcano on 4-5 Sep is pieced together, it appears that the eruption was probably a mainly explosive event while evidence of significant lava flows on the flanks becomes less. The observed "lava flows" could have been bush fires ignited by hot ejecta. In any case, there is little doubt that the observed ash cloud was the result of a significant explosive eruption and not just landslides on the steep flank.

In the meanwhile, the mountain has calmed down and only weak thermal anomalies are being detected on the summit. It would be imprudent to say that the eruption is over. If this is indeed the start of a major explosive cycle, more eruptions could follow in the next weeks and months. Field investigations are under way.