© Charles Chandler

 

I agree that this is contentious, and I'm debating whether or not I can rely on the common interpretation of the so-called magnetic striping. Fischer doesn't think that the data are reliable enough to discount shock dynamics. The implication for my work is that without polarity inversions, I don't have to explain differential rotation, much less torsional oscillation (where the layers take turns being the fastest, thereby generating the dominant field). Nothing else in my theory relies on polarity inversions. So I could take this piece out, and not lose anything else. Right now, I'm thinking about just glossing over the issue. Until/if/when I've had a chance to actually study the striping issue in greater detail, I don't want to take a position. If I had to guess, I'd just take Fischer's word for it. I'm just not sure that he started with the striping data, or came back later and explained it away, after he was already confident that shock dynamics had so much going for it that only incontrovertible evidence need be considered, and the striping data are not. My personal opinion is that he's fundamentally right about shock dynamics, but I think that the whole process took more than a day — the impact created an initial acceleration, but that isn't what got the continents where they are now. It's possible that the mountain building happened in a day. But I think that the continents might have only moved a couple hundred miles due to the impact, and since then, have been creeping along for other reasons, such as my "tectonic ratcheting" hypothesis. That would explain rift valleys inside mountain ranges that have no place in shock dynamics, but would definitely result from the tensile strain of "tectonic ratcheting". I also don't see the transform faults along the mid-ocean ridges as characteristic of an instantaneous continental separation. Since the "striping" is consistent, despite being offset by transform faults, it's reasonable to think that the stripes formed first (somehow), and then they were offset by transform faults. That wouldn't have happened in a day — everything would have been molten, and then it would have solidified as one monolithic, homogenous block. So I think that there are two things going on here: shock dynamics first, and then tectonic ratcheting thereafter. Still, Fischer's dismissal of the striping data might be legitimate, even if he had an ulterior motive. ;)