A very large storm was coming. It had been predicted for days. I saw it was only going to last half a day, and I love storms at the cottage, so I went up anyway. The pre-storm had SW gales up to 50 klicks, and I was enjoying it on the deck. We have a high view, so I can see everything. The waves were 2 feet on our end of the lake, but the south half has the whole reach in the SW direction, and it always builds up a good wave, much higher.
So, it was with great surprise, that I saw an entire day-care centre paddling broadside to the waves right under my nose. I was the only one in the bay, and practically the only one on the lake. The had 2 adult paddlers towing another canoe with 3 5-year-olds. The other canoe had 2 ten-year-olds and a grandma at the back. It was amazing they came this far in the full reach. They should have taken the north shore which was in the lee of the wind. Even if they had done this, they wouldn't have survived the main reach.
They were paddling in circles, well flagged, and being driven against the cliff. I still couldn't believe what I was seeing, but I got the big boat ready. I knew it was a nasty storm because my cell signal had completely vanished, and I couldn't get a radar picture for the thunderstorms. I kept looking at the sky.
By the time I got there, the mom was out of the canoe trying to hold it away from the cliff. I said to them that I could tow them, or we could wait out the storm. They were in a hurry, and there was nothing happening in the sky. If something had been bearing down on us, they wouldn't have had a choice. The adults, brother and sister, decided they would paddle, and I towed the rest. Halfway there, it was too dangerous, so I put everybody in the boat. The tiny kids were terrified of Roxie the rescue dog, but we threw them in anyway. Roxie was very polite.
I towed the empty canoes to the marina, and was surprised to see the OPP boat. There was nobody on the lake for them to harass. I said hi, and told them what we were doing, and they just wanted to know if we were okay. I suppose they were responding to something.
Dumping them at the marina, I went back for the two paddlers. They had just got into the full reach, and I was watching them paddle as hard as they could and not getting anywhere. I had been in that situation many times. So I came in close, dinged the damn prop, and got them loaded up. They were so nice, they wanted to cross the nasty strait, but I said their family was waiting for them
Reminded me when I was in a camp and we were in the same situation. I think I was 12. A cottager rescued the whole group. We pay these things forward.
Safety Note – Canoeing is like driving the 401 in winter. You have to allow for a bad day, and just stay put. Do not be crazy. There is no way these guys would have made it, and I've seen the lake much worse. They were lulled by the lake being glass smooth the last time they went. Today it is glass smooth again.
Wednesday, July 8, 2015
Thursday, July 2, 2015
Effective Stress - Part 4
Ok, enough of the basics, it'll just zoom over the heads of all those 'non-math' scientists who seem to control our lives through oral skills.
Let's get down to injection. If I insert my hose into a bed of clay, nothing much happens. The water stops, since the clay is impermeable, that is, a very low permeability. I can pump up the water, which produces a very high pressure gradient in the clay, but no work is done (work is energy, or force times distance).
I can then put my hose into a bed of gravel. I can turn up the pumps, and get a huge flow. However, there is virtually no pressure gradient, because the gravel is extremely permeable. The gravel doesn't move.
Weird things only happen when I get a pressurized channel, which happens when I inject into shale. In that case, I get the best of both worlds, the channel is permeable (but blocked at the end), and the shale is not. There is a high pressure gradient, and available energy. The shale parts on a bedding plane, and my pumps are howling with the flow. Tremendous work is being done, as I crack apart the rock.
So, seismologists are lost when you have a real situation, such as a fault. To pry the fault apart, and allow slip, you need a pressure gradient, normal to the fault (right angles to). If the rock is as permeable as the fault, then you can't get a pressure gradient no matter what you do. The losers at my old company unnecessarily anchored lots of dams because they measured water pressure under the dam. But the concrete was as permeable as the rock, so no pressure gradient. They thought the water pressure would lift the dam, and send it down the river. Just one more thing that contributed to my breakdown. :)
In the Precambrian rock under Oklahoma, you either have open-channel flow, or the rock is tight. You can't form any gradients in open channels. That is why they are able to inject huge amounts of water. No pressure gradient, no effect on faults. The granite will never act like shale being fractured and pried apart.
There you have it. The USGS and 'consensus science' has it all wrong. That is why you have earthquakes where there aren't any high-flow injection wells. There is another reason, and I've gone over it enough -- stress corrosion.
End of lecture
Let's get down to injection. If I insert my hose into a bed of clay, nothing much happens. The water stops, since the clay is impermeable, that is, a very low permeability. I can pump up the water, which produces a very high pressure gradient in the clay, but no work is done (work is energy, or force times distance).
I can then put my hose into a bed of gravel. I can turn up the pumps, and get a huge flow. However, there is virtually no pressure gradient, because the gravel is extremely permeable. The gravel doesn't move.
Weird things only happen when I get a pressurized channel, which happens when I inject into shale. In that case, I get the best of both worlds, the channel is permeable (but blocked at the end), and the shale is not. There is a high pressure gradient, and available energy. The shale parts on a bedding plane, and my pumps are howling with the flow. Tremendous work is being done, as I crack apart the rock.
So, seismologists are lost when you have a real situation, such as a fault. To pry the fault apart, and allow slip, you need a pressure gradient, normal to the fault (right angles to). If the rock is as permeable as the fault, then you can't get a pressure gradient no matter what you do. The losers at my old company unnecessarily anchored lots of dams because they measured water pressure under the dam. But the concrete was as permeable as the rock, so no pressure gradient. They thought the water pressure would lift the dam, and send it down the river. Just one more thing that contributed to my breakdown. :)
In the Precambrian rock under Oklahoma, you either have open-channel flow, or the rock is tight. You can't form any gradients in open channels. That is why they are able to inject huge amounts of water. No pressure gradient, no effect on faults. The granite will never act like shale being fractured and pried apart.
There you have it. The USGS and 'consensus science' has it all wrong. That is why you have earthquakes where there aren't any high-flow injection wells. There is another reason, and I've gone over it enough -- stress corrosion.
End of lecture
Effective Stress - Part 3
All those points contacting the grain express the full vector surface forces including shear. Since the grain is at rest, the forces sum to zero. When the beaker is filled with water, there is a hydrostatic pressure gradient. Within the water itself, these forces balance to zero, and there is no flow, but the grain is exposed to a gradient.
The pressure is greater on the bottom than on the top. So if sum the forces, there is uplift, which is called buoyancy. The skeleton stresses on the grains are reduced, that is, the effective stress is reduced. Now, here's the thing that loses seismologists. If we filled the beaker with more water, or we attach a big pressure hose, there is no difference. The gradients remain the same.
If we attach a hose to the bottom, and start injecting water, we get an unbalanced pressure gradient in the water, and it begins to flow upward (if we allow it to). If we sum the forces on the grain, we find the balance goes to zero if the gradient keeps increasing, until it becomes zero, and the grain has no effective stress. That is quick sand. (Let's ignore viscous drag.)
If we reverse the pressure gradient downwards, then the effective stress increases, and the sand becomes as hard as rock.
The pressure is greater on the bottom than on the top. So if sum the forces, there is uplift, which is called buoyancy. The skeleton stresses on the grains are reduced, that is, the effective stress is reduced. Now, here's the thing that loses seismologists. If we filled the beaker with more water, or we attach a big pressure hose, there is no difference. The gradients remain the same.
If we attach a hose to the bottom, and start injecting water, we get an unbalanced pressure gradient in the water, and it begins to flow upward (if we allow it to). If we sum the forces on the grain, we find the balance goes to zero if the gradient keeps increasing, until it becomes zero, and the grain has no effective stress. That is quick sand. (Let's ignore viscous drag.)
If we reverse the pressure gradient downwards, then the effective stress increases, and the sand becomes as hard as rock.
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