The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity at Lewotobi Laki-laki had significantly declined during the previous few weeks. Seismic data showed decreased activity; specifically, signals indicated fluid movement at depth and not magma migration towards the surface. There was also a lack of shallow volcanic earthquakes indicating no significant pressures higher in the conduit. The intensity of surficial activity decreased during 1-7 December, with fluctuating avalanche earthquake signals due to instability of material on the flanks. Deformation data showed a decreasing trend during October-December. On 8 December the Alert Level was lowered to 3 (the second highest level on a scale of 1-4) and the public was warned to stay 6 km away from the center of Laki-laki.

Geological Summary. The Lewotobi edifice in eastern Flores Island is composed of the two adjacent Lewotobi Laki-laki and Lewotobi Perempuan stratovolcanoes (the "husband and wife"). Their summits are less than 2 km apart along a NW-SE line. The conical Laki-laki to the NW has been frequently active during the 19th and 20th centuries, while the taller and broader Perempuan has had observed eruptions in 1921 and 1935. Small lava domes have grown during the 20th century in both of the summit craters, which are open to the north. A prominent cone, Iliwokar, occurs on the E flank of Perampuan.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)