Saturday, June 19, 2010
geomorphology has come to an end. This year's field camp was
exceptionally good. Managed to get 24 students well up to speed on
intracanyon lava flows, immense and numerous landslides, and
catastrophic flood deposits in a matter of days. Most of the students
will agree that they got nearly a semester's worth of education in one
week. This year we mapped part of the Hole in the Ground along the Owyhee
River and camped at Birch Creek. A brilliant plan.
Thursday, June 10, 2010
Attabad spillway video: "Thanks to a number of people for drawing my attention to the Hunzaonline video on youtube that shows the spillway in action. The caption indicates that this was collected on the 8th June:
Three observations about this video:
- It shows that the major restriction on flow is still the large boulder at the saddle of the spillway;
- A second boulder has formed substantive constriction downstream as well, but this is not controlling the overall flow
- There is still considerable scour occurring, especially on the downstream side of the boulder, upstream of the boulder towards the neck of the channel, and elsewhere on the banks of the channel.
In case anyone was wondering, that expert is not me! Whilst I wouldn't completely rule out the possibility of a controlled blast, this would need to be undertaken with extreme care, and only after a full analysis of the consequences had been undertaken. I would in particular want to see an evaluation of the likely flood that the blast might trigger, and the potential for triggering further slides on the sides of the valley. However, this is not an excuse for inaction - NDMA really need to move quickly now to evaluate the range of options, and to communicate the pros and cons more widely.
As per my post yesterday, I will use the Hunza Monitoring Site to host updates on the situation at Attabad, and this site to provide a commentary. I will put a new set of data on the monitoring blog later this morning.
Wednesday, June 9, 2010
Tuesday, June 8, 2010
For various reasons, I have dropped the Clark County mega-mega map for a day to work on the very nearly complete Owyhee River area map. In real life, this map is 40 inches by 40 inches at 1:36,000. Although I have compiled the mapping in the river corridor down to about 1:4500 in most places. Heading out to teach field camp there in a couple of days. Learned some handy new tricks in ArcGIS that really have improved map data management and symbolization. Will share them when my cloning experiment is successful.