Mantle Convection, Mid-Ocean Ridges or Rises (MORs) and Trenches

The idea of mantle convection dates back at least to the 1920's, e.g. see Holmes, 1929 (left) Note, however, that convection cells "know their place" and stay below the crust - even though they may push the crust up a bit where they rise and are "hot"

I did not know before I read Menard (1986) a few days ago (SHAME!) that in the same nearby town of Hershey, PA where we own an RCI time-share apartment, and where a recent controversy raged about the Milton Hershey Foundation threatening to sell its major share in Hershey Chocolat...well, that in that very same town an important meeting was held in 1950 which concluded that . . . (look it up yourself, please!)

---

BLO fecit 20021026 corr.20051029 - next page - contents
COMMENTS, PLEASE ?

...... or may drag down part of the crust where they have cooled and sink down, forming some bulge which Vening Meinesz named a "tectogene" (right)

In honor of the giant Vening Meinesz who went down in both Dutch and American submarines in the 1920's and 1930's, I not only selected the appropriate yellow background color, but also link once more to our old friend Richard Field