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Why is radiometric dating less useful to date sedimentary rocks than igneous rocks?
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Radiometric dating is least useful for dating what type of rocks?
Sedimentary Rocks
Could radioactive dating only be used for igneous rocks?
Radioactive dating is only useful in dating igneous and metamorphic rock. Organic material that has not fossilized and does not exceed 70,000 years of age can be dated by Carbon dating techniques. Sedimentary rock can only be dated by its association with igneous and metamorphic rock.
How can you tell the relative age of a sedimentary rock?
This an area of common misconception. Most sedimentary rock, and the fossils contained therein cannot be dated directly with radiometric techniques, but can be dated indirectly. Here's the facts:Because most sedimentary rock is composed of particles of pre-existing rock of various types, each particle can be a different age.Carbon-14 or carbon dating techniques can only be used to date organic material which is of a maximum age of 70,000 years; this leaves out the vast majority of fossils found in rock, and only covering roughly .000016 percent of geologic time.The dating of fossils was originally done by their placement in a geologic column of rock strata. Because of the Law of Superposition, the deeper the stratum, the older it is (in an undisturbed body of rock or sediment). Fossils which were evident in a particular stratum, but missing from other strata were noted as "index" fossils. The presence of these fossils indicated the age of the stratum relative to other layers. The layers of stratum were placed in a geologic column, subdivided, and assigned names based on the presence of different types of fossil organisms. The use of fossils in this manner is known as biostratigraphy and is the basis of "relative dating" of rock layers and fossils, a dating technique that was in effect until the advent of radiometric techniques in the twentieth century.Radiometric dating of rock involves the measurement of the amount of decay in radioactive elements which are present in the rock. Radioactive elements decay at unique rates, depending on the isotope. This rate of decay is known as half-lives, it is the time necessary for ½ of the atoms to decay in a particular element. The decay follows a geometric scale, in that in the first half-life of an element, ½ of the atoms decay, yet in the second half-life, ½ of those remaining decay and so forth. By measuring this decay, and knowing the half life of an element, scientists can date a sample. Radiometric dating is particularly useful in dating igneous and metamorphic rock.Because of geologic events such as plate tectonics and volcanism, suitable material for radiometric dating, such as volcanic tuff, solidified lava, and igneous intrusions have been found as layers on, in, and cut through layers of sedimentary rock. Intrusions are always younger than the rock body they penetrate, meaning that the sedimentary rock in which intrusions are found will be older than a radiometrically dated sample of the intrusion. Lava flows and volcanic ash which form layers in rock will be younger than the rock below and older than the rock above. The solidified intrusions and lava flows can be dated with radiometric techniques.The radiometric dating of suitable rocks (i.e. igneous or metamorphic) in proximity to their sedimentary counterparts, therefore allows the sedimentary rock to be dated as well.
What characteristics make igneous rocks useful?
Many igneous rocks are hard, dense, and durable. This makes them great for tools and building materials.
Sedimentary rocks are useful as records of past time because of?
Their layered structure :)
Radiometric dating is not useful to directly determine the age of?
sedimentary
Radiometric dating is least useful for dating what type of rocks?
Sedimentary Rocks
Radiometric dating is not useful to directly determine the age of rock.?
sedimentary
Can use radiometric dating on all minerals to tell their absolute age?
No, radiometric dating can only be used on certain minerals that contain radioactive isotopes. These minerals include zircon, potassium feldspar, and biotite, among others. Not all minerals contain radioactive isotopes, so radiometric dating cannot be applied to all minerals.
Could radioactive dating only be used for igneous rocks?
Radioactive dating is only useful in dating igneous and metamorphic rock. Organic material that has not fossilized and does not exceed 70,000 years of age can be dated by Carbon dating techniques. Sedimentary rock can only be dated by its association with igneous and metamorphic rock.
Can all radioactive isotopes be used in radiometric dating?
No, not all radioactive isotopes be used in radiometric dating. Some have very very short half lives and would entirely disappear before any useful period of time passed.
How do scientist determine the age of the solar system?
Relative Dating:The dating of fossils was originally done by their placement in a geologic column of rock strata. Because of the Law of Superposition, the deeper the stratum, the older it is (in an undisturbed body of rock or sediment). Fossils which were evident in a particular stratum, but missing from other strata were noted as "index" fossils. The presence of these fossils indicated the age of the stratum relative to other layers. The layers of stratum were placed in a geologic column, subdivided, and assigned names based on the presence of different types of fossil organisms. The use of fossils in this manner is known as biostratigraphy and is the basis of "relative dating" of rock layers and fossils, a dating technique that was in effect until the advent of radiometric techniques in the twentieth century.Absolute Dating:Radiometric dating of rock involves the measurement of the amount of decay in radioactive elements which are present in the rock. Radioactive elements decay at unique rates, depending on the isotope. This rate of decay is known as half-lives, it is the time necessary for ½ of the atoms to decay in a particular element. The decay follows a geometric scale, in that in the first half-life of an element, ½ of the atoms decay, yet in the second half-life, ½ of those remaining decay and so forth. By measuring this decay, and knowing the half life of an element, scientists can date a sample. Radiometric dating is particularly useful in dating igneous and metamorphic rock.Because of geologic events such as plate tectonics and volcanism, suitable material for radiometric dating, such as volcanic tuff, solidified lava, and igneous intrusions have been found as layers on, in, and cut through layers of sedimentary rock. Intrusions are always younger than the rock body they penetrate, meaning that the sedimentary rock in which intrusions are found will be older than a radiometrically dated sample of the intrusion. Lava flows and volcanic ash which form layers in rock will be younger than the rock below and older than the rock above. The solidified intrusions and lava flows can be dated with radiometric techniques.The radiometric dating of suitable rocks (i.e. igneous or metamorphic) in proximity to their sedimentary counterparts, therefore allows the sedimentary rock to be dated as well.
What makes protactinium useful?
Protactinium is not a useful element.The ratio Pa-231/Th-230 in natural sediments is used to radiometric dating up to 175 000 years ago.
Why are fossils useful adjuncts to radiometric dating techniques in determining the age of rock specimens?
Index fossils, which are geographically widespread, of a quickly evolving specie, and only present in sedimentary strata of a particular geologic age, are generally reliable in setting a general time range for the age of a rock specimen.
What isotopes is most useful for dating plant and animal remains?
CARBON DATING The most common fossil dating techniques are radiometric dating techniques. Radiometric dating uses knowledge of the decay rates of unstable ( radioactive ) nuclei to determine, by comparison with the proportion of stable nuclei in a fossil sample, the date of the introduction of the radioactive material into the live organism, especially if the isotope was ingested while the organism was alive.
How reliable is fossil evidence?
The answer depends on how the word 'reliable' is interpreted in the question:(1) Is the fossil evidence 'reliable' in interpreting the history of life on Earth?Fossil evidence IS our understanding of the history of life. Fossils on which this understanding is based include skeletons, roots, leaves, bark, chemical signatures, imprints, carbon residues, burrowing and trail marks, petrified wood, footprints, eggs, gastric stones, fecal matter, and many others, found preserved mainly in stone, but sometimes in ice. There are many ways that fossils can be formed. They include freezing, carbonization, petrification, mineral replacement, unaltered preservation,recrystallization, andauthigenicpreservation.The fossil record of life recorded in rock is full of periods of intense diversification, appearances of new lifeforms, and extinction events that affected large percentages of the biota on a worldwide scale.(2) Are the modern methods used to determine the age of the fossil 'reliable'?Radiometric dating of rock involves the measurement of the amount of decay in radioactive elements which are present in the rock. Radioactive elements decay at unique rates, depending on the isotope. This rate of decay is known as half-lives; it is the time necessary for ½ of the atoms to decay in a particular element. The decay follows a geometric scale, in that in the first half-life of an element, ½ of the atoms decay, yet in the second half-life, ½ of those remaining decay and so forth. By measuring this decay, and knowing the half life of an element, scientists can date a sample. Radiometric dating is particularly useful in dating igneous and metamorphic rock, but not so much for sedimentary rocks and fossils.Because of geologic events such as plate tectonics and volcanism, suitable material for radiometric dating, such as volcanic tuff, solidified lava, and igneous intrusions have been found as layers on, in, and cut through layers of sedimentary rock and fossils. Intrusions are always younger than the rock body they penetrate, meaning that the sedimentary rock in which intrusions are found will be older than a radiometrically dated sample of the intrusion. Lava flows and volcanic ash which form layers in rock will be younger than the rock below and older than the rock above. The solidified intrusions and lava flows can be dated with radiometric techniques.The radiometric dating of suitable rocks (i.e. igneous or metamorphic) in proximity to their sedimentary counterparts, therefore allows the sedimentary rock to be dated as well. Radiometric dating techniques are constantly being refined and improved with a resulting increase in accuracy and date range.Scientific inquiry and the scientific method have contributed greatly to our lives in the fields of electronics, physics, engineering, chemistry, manufacturing, and medicine. This same scientific method is being used in genetics and Earth sciences to broaden our knowledge and understanding of Earth's history, including the origin and evolution of life.
Why are sedimentary rocks useful to scientists'?
Mainly because the fossils of plants and animals preserved in the sediment layers allow dating of events that happened before humans existed.
