|
kringle_mining 03:55:39 Wed Oct 13 2010 |
 It is the structural feature that forms the finger heading up the side of the Mountain at the mouth of Demar Creek. The black on the quartz veins is mostly lichen The red line in the map below is the finger that the vein forms. See how the vein which disappears under a beaver pond blocks any concentrates from escaping into the river. Demar is walled off with a shallow hump of qtz vein.  |
|
kringle_mining 04:56:34 Wed Oct 13 2010 |
 Visible in the back ground beneath the three close birches is a portion of the vein. |
|
kringle_mining 05:15:16 Wed Oct 13 2010 |
Below are two barriers. The horse shoe is a plunging anticlinal fold in the bedrock schist  The oxbow ponds are perpendicular to the current flow of Ottertail Creek. The shallow depth of gravels here suggest an barrier causing this topographic feature This barrier could be: 1. an up thrown fault 2. a basalt dike ( basalt bolders are found while dredging) 3. a prominent quartz vein (large boulder found while dredging) 4. Two more plunging anticlinal folds |
|
kringle_mining 20:08:37 Thu Oct 14 2010 |
|
|
outnaboutnak 03:39:00 Fri Oct 15 2010 |
|
|
Geo_Jim 05:49:53 Sun Apr 24 2011 |
Sorry it took so long for me to reply. Yes, I think you have interpreted the geology correctly. The quartz vein or rock ridge could be cutting across the valley floor acting as a dam/riffle. It sort of thing does happen. The former creek would be channeled by the outcrop and impact the gold distribution accordingly. Geo Jim:smile: |
|
kringle_mining 15:05:16 Wed Apr 27 2011 |
I will be dredging this portion of the creek in late May 2011 (circled area in map below). If you can find time in your schedule this Summer to come up to Ottertail and Demar for a visit, I will come down river and pick you up with the airboat. I am going up to UAF within the next couple of weeks to rock,chaulk talk with Rainer Newberry to discuss lithologies in this area, and to confirm his airboat ride. 
|