Please answer in full detail for each question: 1. why was the discovery of pale
ID: 803725 • Letter: P
Question
Please answer in full detail for each question:
1. why was the discovery of paleomagnetic bands on the atlantic ocean floor such as important turning point in the acceptance of the theory of plate tectonics? suppose you could rewrite history so that the satellite measurements of continental drift came first. would the discovery of seafloor spreading still have been important??
2. what are some of the important questions about plate tectonics that remain unanswered today?
3. why do geologists call plate tectonics a unifying theory?
5. what is the tectonic environment of the place where you live or attended school? (Westchester NY). Do you live near a plate margin? if so, what type is it? or do you live in ht middle of a plate? if so, which one?
Explanation / Answer
1.Alfred Wegener gave the theory of continental drift in 1912.The main issues with the theory was that he did not propose how the different land masses could break away from each other and how continents used to fit together.
The answers to these questions were answered by the paleomagnetism - an area of historical geology dealing with studying the direction and intensity of magnetic field in the past by studing the residual magnetic properties of rocks.
When oceanographers surveyed the floor of atlantic ocen with magnetometer ,it came as a surprise to them asthe sea floor consist of magnetized rocks with alternating bands of normal and reversed polarities.The bands were 100 km long and were symmetrical on the either side.The process of sea floor spreading was also confirmed.
Hence the discovery of paleomagnetic bands in the atlantic ocan floor remioved the shortcomings of the plate tectonic theory.
2.Some of the unanswered questions about plate tectonic theory are what drives the tectonic plate motion ?The heat released from the interior of the earth can contribute to this but this is a very complesx process .Hence the details of earth's mantke - crust interaction ,plate motion,convection of mantle are still unanswered.
3.Although Plate tectonic doesnot answer some of the questions ,yet its able to coherently provide so many geologoc features of the earth system .Hence its called the unifying theory.Some of the features are:-
- structural geology - faults, folds, unconformities, thrust faults, etc
- earthquakes,volacnoes
-existence of ocean basins and continents
-mountain formation process
-velocity of p and s seismic waves