************************************** From: Shellie Rose <srr13@xxxxxxxx> ************************************** The eruption and emplacement of a long lava flow continues at Klyuchevskoy Volcano (~30 km southwest of the town of Klyuchi) on the Kamchatka Peninsula, Russia. This activity is being closely monitored by the Kamchatka Volcanic Eruption Response Team (KVERT), and more remotely by the University of Pittsburgh using the ASTER imaging instrument on the NASA Terra satellite. The color code of Klyuchevskoy was initially raised by KVERT from yellow to orange on 15 January 2007 due to increased ash explosions, gas/steam plumes, lava flow emplacement, and increasing volcanic tremor. Recently (16 May) the color code was raised to red with the detection of a stronger tremor and the potential for large (10 km ASL) ash plumes. To support the monitoring of this remote volcano, the ASTER urgent request protocol has been utilized several times since February. The most recent (12 May) data can be seen here: http://ivis.eps.pitt.edu/data/Kamchatka/12May2007_Klyuch.pdf http://ivis.eps.pitt.edu/data/Kamchatka/12May2007_Klyuch2.pdf Previously, ASTER data from 26 April revealed a substantial thermal anomaly along the northern flank of the volcano associated with two lava flows extending up to 4 km in length with associated 3 km long lahars. However, new day and night data acquired on 12 and 13 May, respectively show that this anomaly has continued to increase in thermal output since the first clear ASTER image of the summit (21 February). The ASTER data are 15m/pixel in the visible/near infrared (VNIR), 30 m/pixel in the shortwave infrared (SWIR), and 90m/pixel in the thermal infrared (TIR) regions. The VNIR data show a diffuse plume partially covering the summit and extending to the northeast off the image (greater than 60 km). A decorrelation stretch performed on both the day and night TIR data indicates that the plume is primarily composed of water and ice. Silicate-rich ash was also detected along the northern and southern perimeters of the plume, however this appears be at a lower elevation and likely originates from a new eruption of Bezymianny Volcano, approximately 9.5 km to the south of Klyuchevskoy. Mixing of the plumes is occurring distally to the northeast. A recent KVERT information release on 11 May indicates ash fall in the town of Klyuchi originating from both Klyuchevskoy and Bezymianny. A significant increase in thermal output has been occurring since the first ASTER acquisition in February, as the number of thermally elevated and saturated pixels has more than tripled. The ASTER SWIR data collected on 12 May reveal significant thermal output over the lava flows. The maximum non-saturated pixel temperatures of the lava flow range from 333 C around the perimeter to 446 C near the central, saturated pixels. Over 100 SWIR pixels within the flow were saturated despite the data being collected in the low gain (high temperature) mode. Temperatures well above these levels would commonly produce incandescence in the visible wavelengths. Incandescence was detected in the VNIR data on 26 April in two distinct open channels containing lava flowing down the steep slopes. However, in the most recent VNIR data, no incandescence was detected in the northwestern lava channel. It is still easily detectable in the main northern channel, suggesting primary lava effusion has concentrated there. ASTER TIR from 12 May show a thermal anomaly up to 120 m wide and 1.6 km in length where it becomes obscured by low-lying clouds. Numerous TIR pixels 10 degrees or more above the average background temperature of –7.2 C are seen. The size and thermal output of the open-channel lava flow is causing 31 TIR pixels (0.25 sq. km) to be at or above the saturation level (> 97 C). Reports by KVERT detail explosive strombolian activity and lava flow effusion along the northwestern flank initiating on 28 March and continuing to the present. The northwestern lava flow appears to have cooled to near background temperatures (-4 to -7 C) since 26 April, further supporting the conclusion derived from the SWIR data that the primary effusion has focused on the north channel. ASTER will continue to monitor the volcano to assess changes in the thermal and gas flux throughout this phase of activity. New ASTER day/night data acquisitions are scheduled for the 20/21 May and the 28/29 May. Shellie Rose srr13@xxxxxxxx Michael Ramsey mramsey@xxxxxxxx ============================================================== To unsubscribe from the volcano list, send the message: signoff volcano to: listserv@xxxxxxx, or write to: volcano-request@xxxxxxxx To contribute to the volcano list, send your message to: volcano@xxxxxxxx Please do not send attachments. ==============================================================
