0
Because lava can melt iron (demagnetizing it) and when it solidifies, it will pick up whatever magnet field it is currently subject to, thus locking in a record of the magnet field at the time in history.
Wiki User
∙ 13y ago
Add your answer:
Earn +20 pts
What is the study of the magnetic record preserved in Earth's rocks called?
paleomagnetism
Why are there magnetic strips on the ocean floor what do they mean?
The earth maintains a magnetic field due to the metals that make up its core. Thus, all rocks are influenced by this magnetic field and "face" the direction the field is "facing". Every few hundred million years the poles switch, and with it the magnetic field. Similarly, all rocks "face" the new direction. Magnetic strips are indicators of when the magnetic field of the Earth changed.
What is paleomagnetism used to identify?
The Earth's Magnetic field and magnatizum in the rocks.
Which aspect of magnetic reversal provides evidence of continental drift?
Periodically, the magnetic field of the earth reverses polarity. The direction of the magnetic field is recorded in the magnetic properties of rocks when they are erupted. Rocks are being continuously added at sea floor spreading regions, and thus the magnetic reversals are recorded as pairs of parallel 'stripes' alongside the mid ocean spreading ridge.
Why an electromagnetic wave is able to produce both an electric field and a magnetic field because?
The question founders on the rocks of a chicken/egg conundrum. The presence of both an electric field and a magnetic field is required in order to produce an electromagnetic wave.
What can the orientation of a rocks magnetic field can tell you?
The orientation of a rocks magnetic field can tell you it's relative age.
Why is it believed that the Earth's magnetic field has reversed its polarity in the past?
By observing magnetic rocks in geological deposits.By observing magnetic rocks in geological deposits.By observing magnetic rocks in geological deposits.By observing magnetic rocks in geological deposits.
How can the magnetic field of the Earth be sued to estimate the age of rocks found in the Earth?
By knowing the precise orientation of the rocks magnetic field, you can compare its magnetic field direction to the known direction of the magnetic field over time since the "north pole" wanders over time. The rock locked in its magnetic field when it cooled from magma.
What are rocks that exhibit magnetism that is opposite to the current magnetic field?
magnetic fields
Identify how magnetic symmetry can be used as evidence of sea floor spreading?
As the sea floor spreads the magnetic orientation in the rocks as they cooled is preserved. As the earth's magnetic field changes then a distinct pattern is imprinted in the rocks. If sea floor spreading is true then this unique pattern should be the same on both sides from the spreading point. Measurements of sea bottom rocks verify this symmetry is true. :)
What is the study of the magnetic record preserved in Earth's rocks called?
paleomagnetism
The orientation of a rock’s magnetic field can tell you its?
The orientation of a rocks magnetic field can tell you it's relative age.
The alignment of iron minerals in rocks when they are formed reflects the fact that Earth's has reversed itself several times in the past?
magnetic field.
What techique is used to study ancient magnetic fields?
Paleomagnetism refers to the study of the record of the Earth's magnetic field preserved in various rocks and minerals through time.The study of paleomagnetism is possible because iron-bearing minerals such as magnetite may record past directions of the Earth's magnetic field when the rocks containing them were formed or last heated up.Paleomagnetic signatures in rocks can be recorded by three different mechanisms:-First, iron-titanium oxide minerals in basalt and other igneous rocks may preserve the direction of the Earth's magnetic field when the rocks cool through the "Curie temperature" for those minerals. (The Curie temperature of magnetite, is about 580°C).In a completely different process, magnetic grains in sediments may align with the magnetic field during or soon after deposition.In a third process, magnetic grains may be deposited from a circulating solution, or be formed during chemical reactions, and may record the direction of the magnetic field at the time of the mineral's formation.
Why are there magnetic strips on the ocean floor what do they mean?
The earth maintains a magnetic field due to the metals that make up its core. Thus, all rocks are influenced by this magnetic field and "face" the direction the field is "facing". Every few hundred million years the poles switch, and with it the magnetic field. Similarly, all rocks "face" the new direction. Magnetic strips are indicators of when the magnetic field of the Earth changed.
Does the formation of metamorphic rocks depend on the magnetic field?
no it has nothing to do with it
How is the polarity of Earth's magnetic field recorded in the sea floor?
The polarity of the Earth's magnetic field is recorded in igneous rocks, and reversals.
