Variations in sediment runoff in the lower reaches and the delta of the Kuban River in the XX–XXI centuries

Data of network and expedition measurements and information about water management arrangements were used to study in detail the peculiarities of along-channel and long-term variations in the major characteristics of suspended sediment runoff in the lower reach and the delta of the Kuban River. For characteristics periods, the annual volumes of actual and estimated sediment runoff and the contribution of economic activity in its variations are evaluated and possible changes in sediment runoff characteristics in the XXI century are forecasted. The specific features, values, and causes of sediment runoff transformation in Kuban delta in the past and the present are analyzed; sediment balance in the delta is calculated.     

The 2010–2012 eruption of Kizimen Volcano: The greatest output (from the data of remote-sensing observations) for eruptions in Kamchatka in the early 21st century part I. The November 11, 2010 to December 11, 2011 phase

This paper presents the results from the detailed analysis of aerial photographs and space images for the Kizimen area, which characterize the geologic and geomorphologic effects of the ongoing eruption over the 2010–2011 period. It is shown that the total volume (>0.5 km³) and total mass (>10⁹ t) of the discharged (resurgent plus juvenile) material makes this eruption the most productive in Kamchatka for the first 12 years of the 21st century. The dominant component (>90%) is juvenile material with andesitic composition. The pyroclastics (tephra, deposits of the juvenile pyroclastic avalanches and incandescent debris avalanches) comprise >0.3 km³and >0.45× 10⁹ t, the lava (a very thick block lava flow 3.052 km long and 2.163 km² in area) occupies about 0.195 km³ and 0.45 × 10⁹ t. With the exception of the tephra, which fell over an area of about 100000 km², the rest of the material was accumulated on the Kizimen cone and at its base. The mean discharge rate of juvenile ejecta was about 15 m³/s (29 t/s) for 13 months (November 11, 2010 to December 11, 2011). Appreciable changes also occurred at the near-summit part of the volcano’s cone.