US
57 MIN READ TIME

EARTH’S STRUCTURE AND MINERAL COMPONENTS

When I was working on my Master’s Thesis in the 1950s, the idea that the continents had once been together was still an unproven theory. Granted this radical concept had been proposed by Alfred Wegener in 1912 but it had little acceptance, even ridiculed at the time. It was not until the world’s scientists banded together and established the geophysical Year in the 1950s that evidence began to confirm and eventually proved Wegener was right. Once started, the Geophysical program went on and on with scientists sharing information and coordinating their studies. They did research and experiments concentrated on learning what they could about the earth, its structure, continents, geologic history, and minerals.

In my opinion, the most amazing research was the mapping of the hidden ocean floor to learn its structure and composition. Remarkably, a north-south volcanic ridge was discovered jutting up from the mid-ocean floor running the length of the Atlantic seafloor emerging now and then at Iceland. More work revealed this was a huge fault in the earth’s crust continually oozing lava. More importantly, this continuous flow of lava slowly pushed earlier emitted lava from the center of the ocean floor like a conveyor toward the continents. This subtle force actually moved continents apart an inch at a time. This was proven when the volcanic rocks that oozed on the ocean floor were studied. Locked in the rock were iron particles all aligned north-south or south-north showing the earth’s magnetic field had reversed repeatedly and the floor was moving. The oldest Atlantic sea floor is closest to the continents and the younger rocks nearest what we now call the Mid-Atlantic Ridge. This is proof positive the continents are slowly drift ing apart. Matching rock formations on the separated continents later added proof of an earlier togetherness. We now know the continents have and are still moving. The term ‘continental drift ’ is used to describe this crustal movement. The later term Plate Tectonics now describes this action. We now accept the earth’s crust is broken into huge sections or plates separated by major active fault zones.

Read the complete article and many more in this issue of Rock&Gem Magazine
Purchase options below
If you own the issue, Login to read the full article now.
Single Digital Issue August 2019
 
$5.99 / issue
This issue and other back issues are not included in a new subscription. Subscriptions include the latest regular issue and new issues released during your subscription. Rock&Gem Magazine
Annual Digital Subscription $27.99 billed annually
Save
61%
$2.33 / issue
6 Month Digital Subscription $15.99 billed twice a year
Save
56%
$2.67 / issue
Monthly Digital Subscription $4.99 billed monthly
Save
17%
$4.99 / issue