Uranium and uranium dating.pptx
•Download as PPTX, PDF•
0 likes•832 views
Uranium dating is a radioactive dating technique that relies on the decay of uranium isotopes to date archaeological and geological samples. There are three main types of uranium dating: uranium-uranium dating, uranium-thorium dating, and uranium-lead dating. Uranium-lead dating provides the most accurate dates and can be used to determine the age of samples from 1 million to over 4.5 billion years old. Uranium dating techniques are used in applications such as determining the age of dinosaur fossils and dating archaeological sites.
Report
Share
Report
Share
Recommended
Uranium lead method of rock dating
This document discusses radiometric dating techniques used by geologists to determine the age of rocks. It introduces radiometric dating, the concept of half-life, and commonly dated minerals like zircon and monazite. Methods like uranium-lead dating are explained in detail. Instruments used for dating like laser ablation-ICPMS and electron microprobe are also mentioned. The document concludes that radiometric dating, especially uranium-lead dating of zircon, is a reliable method for determining the age of rocks and major geological events.
Mass extinctions
The document discusses extinction and mass extinction events throughout Earth's history. It notes that extinction is a natural part of evolution, with 99.9% of all species that ever lived now extinct. Mass extinctions have occurred periodically, where the extinction rate far exceeds the normal background rate, such as the Permian-Triassic extinction over 250 million years ago where 90-95% of marine species went extinct. Some hypotheses for the causes of mass extinctions include large meteorite impacts, as well as volcanic activity and climate changes.
Dating fossils and rocks
This document discusses various methods for dating fossils and rocks, including carbon-14 dating and radioisotope dating. It explains how these methods work, such as by measuring the ratio of carbon-12 to carbon-14 in a sample. However, it notes that all of these dating methods rely on assumptions, like the starting conditions and decay rates having always remained constant, that are difficult to prove and have been shown to be inaccurate at times by experiments. Therefore, the ages provided by these dating methods are not completely reliable and should be interpreted with caution.
Mass extinction
The document discusses five major mass extinction events that have occurred throughout Earth's history. It provides details on the timing, affected organisms, and hypothesized causes for each extinction. The largest was the Permian-Triassic extinction 252 million years ago, in which over 96% of marine species and 70% of terrestrial vertebrates died off, possibly due to one or more factors including asteroid impact, volcanism, and climate change. Subsequent extinctions discussed are the Ordovician-Silurian, Late Devonian, Triassic-Jurassic, and Cretaceous-Tertiary events. Each had significant impacts on biodiversity and the dominant lifeforms on Earth.
Palaeontology
This document discusses different types of fossils and fission track dating. It describes various ways that organisms can be preserved as fossils, including their entire bodies, original hard parts, skeletons, altered hard parts, and traces. Examples are given for each type like insects preserved in amber. Fission track dating is also summarized as a technique used to date uranium-bearing minerals based on analyzing damage trails left by radioactive decay. Rocks suitable for this method include apatite, zircon, and granite. The document outlines the process of fission track dating and its applications in understanding mountain belts, sediment provenance, and basin thermal evolution.
Radiometric methods for age determination
This document discusses radiometric dating methods used to determine the age of materials such as rocks. It describes four common radiometric dating techniques: 1) Uranium-Lead dating which analyzes the decay of uranium isotopes into lead isotopes, 2) Potassium-Argon dating which analyzes the decay of potassium-40 into argon-40, 3) Rubidium-Strontium dating which analyzes the decay of rubidium-87 into strontium-87, and 4) Carbon-14 dating which is only applicable to once-living materials by analyzing the decay of carbon-14 into nitrogen-14. The document provides details on the radioactive isotopes, daughter products, and half-
Evolution of elephas in paleontology
My seminar
At Periyar University Salem
I'm Thomas chinnappan
Keeranur Pudukkottai tamilnadu India
@tcoftheworld
@tcorganization
SIGNIFICANCE OF CONODONTS IN MICROFOSSIL HISTORY
Conodonts are an extinct group of microscopic fossils that are significant in microfossil history. They are composed of calcium phosphate and resemble eel-like creatures. Conodonts first appeared in the Late Cambrian period and became extinct in the Late Triassic. They are useful for correlating strata and determining environmental factors like climate and water depth due to their abundance and wide geographic range during the Paleozoic era. Their tooth-like elements are prepared and studied using acid treatment and microscopy. Conodonts have been important for biostratigraphy and tracing evolutionary relationships.
Recommended
Uranium lead method of rock dating
This document discusses radiometric dating techniques used by geologists to determine the age of rocks. It introduces radiometric dating, the concept of half-life, and commonly dated minerals like zircon and monazite. Methods like uranium-lead dating are explained in detail. Instruments used for dating like laser ablation-ICPMS and electron microprobe are also mentioned. The document concludes that radiometric dating, especially uranium-lead dating of zircon, is a reliable method for determining the age of rocks and major geological events.
Mass extinctions
The document discusses extinction and mass extinction events throughout Earth's history. It notes that extinction is a natural part of evolution, with 99.9% of all species that ever lived now extinct. Mass extinctions have occurred periodically, where the extinction rate far exceeds the normal background rate, such as the Permian-Triassic extinction over 250 million years ago where 90-95% of marine species went extinct. Some hypotheses for the causes of mass extinctions include large meteorite impacts, as well as volcanic activity and climate changes.
Dating fossils and rocks
This document discusses various methods for dating fossils and rocks, including carbon-14 dating and radioisotope dating. It explains how these methods work, such as by measuring the ratio of carbon-12 to carbon-14 in a sample. However, it notes that all of these dating methods rely on assumptions, like the starting conditions and decay rates having always remained constant, that are difficult to prove and have been shown to be inaccurate at times by experiments. Therefore, the ages provided by these dating methods are not completely reliable and should be interpreted with caution.
Mass extinction
The document discusses five major mass extinction events that have occurred throughout Earth's history. It provides details on the timing, affected organisms, and hypothesized causes for each extinction. The largest was the Permian-Triassic extinction 252 million years ago, in which over 96% of marine species and 70% of terrestrial vertebrates died off, possibly due to one or more factors including asteroid impact, volcanism, and climate change. Subsequent extinctions discussed are the Ordovician-Silurian, Late Devonian, Triassic-Jurassic, and Cretaceous-Tertiary events. Each had significant impacts on biodiversity and the dominant lifeforms on Earth.
Palaeontology
This document discusses different types of fossils and fission track dating. It describes various ways that organisms can be preserved as fossils, including their entire bodies, original hard parts, skeletons, altered hard parts, and traces. Examples are given for each type like insects preserved in amber. Fission track dating is also summarized as a technique used to date uranium-bearing minerals based on analyzing damage trails left by radioactive decay. Rocks suitable for this method include apatite, zircon, and granite. The document outlines the process of fission track dating and its applications in understanding mountain belts, sediment provenance, and basin thermal evolution.
Radiometric methods for age determination
This document discusses radiometric dating methods used to determine the age of materials such as rocks. It describes four common radiometric dating techniques: 1) Uranium-Lead dating which analyzes the decay of uranium isotopes into lead isotopes, 2) Potassium-Argon dating which analyzes the decay of potassium-40 into argon-40, 3) Rubidium-Strontium dating which analyzes the decay of rubidium-87 into strontium-87, and 4) Carbon-14 dating which is only applicable to once-living materials by analyzing the decay of carbon-14 into nitrogen-14. The document provides details on the radioactive isotopes, daughter products, and half-
Evolution of elephas in paleontology
My seminar
At Periyar University Salem
I'm Thomas chinnappan
Keeranur Pudukkottai tamilnadu India
@tcoftheworld
@tcorganization
SIGNIFICANCE OF CONODONTS IN MICROFOSSIL HISTORY
Conodonts are an extinct group of microscopic fossils that are significant in microfossil history. They are composed of calcium phosphate and resemble eel-like creatures. Conodonts first appeared in the Late Cambrian period and became extinct in the Late Triassic. They are useful for correlating strata and determining environmental factors like climate and water depth due to their abundance and wide geographic range during the Paleozoic era. Their tooth-like elements are prepared and studied using acid treatment and microscopy. Conodonts have been important for biostratigraphy and tracing evolutionary relationships.
Radiocarbon dating
Radiocarbon dating is a method for determining the age of organic material by measuring the amount of radioactive carbon-14 remaining in the sample. Willard Libby developed the method in the 1940s, for which he won the Nobel Prize in 1960. It is based on the principle that living organisms absorb carbon-14 from the atmosphere, but after death, the amount of carbon-14 decreases as it radioactively decays. By measuring the amount of carbon-14 remaining and knowing its half-life of 5730 years, the age of the sample can be estimated. Radiocarbon dating has revolutionized understanding of chronologies in archaeology, geology, and other fields, but is limited to dating samples under 60,000 years
Paleontology, types & uses of fossils
Main Topic of Paleontology (Study of Fossils or remains of living organisms), Fossils and Types of Fossils & Significance of Fossils
Classification of micro fossil theory
Microscopic animal
Microscopic Algae
Bacteria
Microfossil of uncertain effinities
Microfossil elements of smaller animal
Microfossil fragments of larger organism
geochronolgy and age of earth
This document provides information about geochronology and dating the age of the Earth. It discusses how the Earth is estimated to be 4.6 billion years old based on dating of meteorites and the oldest Earth rocks. It describes the principles of relative dating methods like superposition and cross-cutting relationships. It also explains numerical dating techniques using radioactive isotopes like potassium-argon and uranium-lead dating to assign absolute ages to rocks in millions or billions of years. Finally, it briefly discusses isostatic adjustment and two hypotheses about isostasy proposed by J.H. Pratt and G.B. Airy.
Geological time scale
The document summarizes the geological time scale which divides Earth's history into different eras, periods, and epochs based on fossil and stratigraphic evidence. It describes the four eons of Earth's history starting with the Hadean and Archean eons of the earliest lifeforms like bacteria. It then outlines the major eras - Paleozoic, Mesozoic, and Cenozoic - describing some of the significant lifeforms, events, and environmental changes that occurred during each period within these eras. The largest unit of the geological time scale is the eon, while the smallest is the epoch.
Fossil ppt
This document discusses different types of fossils and fossilization. It describes fossils as remains or traces of once-living organisms found in rock. There are several modes of fossil preservation discussed, including entire body preservation, entire skeleton preservation, petrification and replacement, molds and casts, imprints, traces and trails, and burrows. The importance of fossils is also mentioned, such as for studying evolution, paleoecology, and paleogeography of ancient life.
U th-pb dating
U-Th-Pb dating involves the radioactive decay of uranium and thorium isotopes into lead isotopes. This method was first used in the early 20th century to determine the ages of rocks. It has since become the most precise dating technique. Uranium-238 decays to lead-206, uranium-235 decays to lead-207, and thorium-232 decays to lead-208. By measuring the ratios of these radioactive and stable lead isotopes to their uranium and thorium parents in a rock sample, its age can be calculated based on the known decay rates. The U-Pb dating method can be used to construct isochrons to obtain more accurate dates, though open system behavior can cause
Phylum mollusca
This document provides information about the phylum Mollusca. It focuses on one class within this phylum, the Bivalvia (Lamellibranchia). Key points:
- Bivalvia are aquatic molluscs enclosed within a calcareous bivalve shell. They lack a head and have gills (lamellae) for respiration.
- The shell consists of two valves joined by a hinge, which are covered internally by the mantle. The mantle forms an enclosed mantle cavity.
- Three main types of dentition exist in the hinge: taxodont, with many small teeth; heterodont, with different sized teeth; and desmodont, replacing teeth with
Classification of brachiopoda
1. The document discusses the classification of brachiopods, a phylum of marine invertebrates. It describes their two main classes, Articulata and Inarticulata, based on whether their shells have articulating features.
2. Within these classes are orders, superfamilies, and families classified by characteristics like shell structure, pedicle features, and internal structures. Over 12,000 fossil brachiopod species have been identified.
3. The classification system presented divides brachiopods into classes, orders, and superfamilies based on features like shell structure, pedicle morphology, and internal structures.
trilobites
The document discusses the phylum Arthropoda, specifically the class Trilobita. Trilobites had a three-lobed body plan divided into three sections - the cephalon (head), thorax (body), and pygidium (tail). Their dorsal surface was protected by a calcareous exoskeleton. Trilobites first appeared in the Lower Cambrian period and became extinct by the end of the Paleozoic era. They exhibited changes over time including a reduction in thoracic segments and variations in eye and glabella morphology.
MORPHOLOGY AND EVOLUTION TREND OF GASTROPOD
The document discusses the class Gastropoda, which includes snails, whelks, and limpets. It describes their morphology, anatomy, shell structures, forms, ornamentation, and evolutionary trends. Key points include: Gastropods have a coiled, spiral shell with an open anterior end called the aperture; their shells come in many forms depending on factors like spire angle and whorl size; and evolutionary trends have led to increased coiling, ornamentation loss, and aperture modification over time in both dextral and sinistral forms from the Triassic to present.
Mass extinction
This document outlines 5 major mass extinction events that have occurred throughout history, along with their estimated time periods, sizes, impacted species, and suspected causes. The largest was the Permian-Triassic extinction 251 million years ago, which led to 96% of species being eliminated. The most recent was the Cretaceous-Tertiary extinction 66 million years ago that wiped out the dinosaurs. Evidence points to large asteroid impacts as playing a role in the latter, while volcanic activity also likely contributed to several extinctions. The document concludes by noting we may be in the midst of a sixth mass extinction currently due to habitat loss and human impacts.
Stromatolites and its stratigraphic implications
This document summarizes the seminar content on stromatolites, including an introduction to stromatolites, their origin and evolution throughout geologic eras from Precambrian to Cenozoic. Key points covered include stromatolites being the oldest known fossil dating to over 3 billion years ago, their significance in changing Earth's early atmosphere, their dominance as the primary lifeform for over 2 billion years, and their increasing rarity today with some modern examples found in Shark Bay, Australia.
Radiometric dating
Radiometric dating uses the decay of radioactive isotopes like carbon-14 and potassium-40 to date rock layers. Radioactive isotopes break down at a steady rate, allowing scientists to measure the amount remaining in a rock to determine its age by comparing it to the original amount. Different isotopes have different half-lives, such as 1.3 billion years for potassium-40 and 5,730 years for carbon-14, enabling the dating of rocks from thousands to billions of years old.
Brachiopods
Brachiopods are marine invertebrates that live in oceans worldwide. They have two shells or valves and a coiled feeding organ called a lophophore. There are two major groups - articulate brachiopods which have teeth and sockets that join the valves, and inarticulate brachiopods which rely on muscles. Brachiopods have been around for over 500 million years and their fossils provide clues about ancient marine environments, though there are fewer living species today.
Evolution of elephant
Evolution is a developmental process from simple to complex form of life. Evolution of elephant started 60mya, from size of a pig. It spread all over world especially Africa and Asia. Today only two species Loxodonta and Elephas exist.
Morphology of ostracods
Ostracods are bivalved crustaceans that are commonly used in micropaleontology and paleoecology research. They have a complex morphology and are found in both marine and freshwater environments around the world. Key aspects of ostracod anatomy include their carapace, hinge patterns, and ornamentation, which are important for classifying and interpreting species. Ostracods first appeared in the late Cambrian and have adapted to occupy nearly all aquatic habitats, with over 2000 known living species today. Their fossil record allows them to be used for biostratigraphy and paleoenvironmental reconstruction.
The Geological Time Scale
The geologic time scale (GTS) is a system of chronological dating that relates geological strata (stratigraphy) to time. Geologists have divided Earth's history into a series of time intervals. These time intervals are not equal in length like the hours in a day. Instead the time intervals are variable in length. This is because geologic time is divided using significant events in the history of the Earth.
Foraminifera , micro fossil
Microfossils are very small remains of organisms 0.001 mm (1 micron) to 1 mm, that require magnification for study.
They are abundant, can be recovered from small samples.
Provide the main evidence for organic evolution through the time
They classified into two groups:
Organic-walled; Acritarchs, Dinoflagellate, Spores and Pollen grains … etc.
Foraminifera Each chamber interconnected by an opening (foramen) or several openings (foramina).
Known from Early Cambrian through to recent times, and has reached its acme during the Cenozoic.
Have a wide environmental range from terrestrial to deep sea and from polar to the tropical region.
Depending on the species, the shell may be made of organic compounds, sand grains and other particles cemented together, or from crystalline calcite.
Inorganic walled; Diatoms, Silicoflagellates, Ostracods, Conodonts, and Foraminifera
Paleomagnetism
Paleomagnetism is the study of ancient magnetic fields preserved in rocks. When rocks form, magnetic minerals within them align with the Earth's magnetic field at that time, recording its orientation. Studying the orientation of these magnetic minerals in rocks from different locations and time periods allows scientists to map changes in the Earth's magnetic field through time and reconstruct movements of tectonic plates. Paleomagnetism provides strong evidence for plate tectonic theory, showing that continents have moved over Earth's history by matching the magnetic signatures of separated landmasses and revealing symmetrical magnetic patterns on either side of mid-ocean ridges from sea floor spreading.
Uranium And Nuclear Elements
Uranium-235 is a fissile isotope of uranium that can undergo nuclear fission when struck by a neutron. When a U-235 atom absorbs a neutron, it becomes Uranium-236 which is unstable and spontaneously splits into two smaller atoms, releasing additional neutrons and a large amount of energy. This fission reaction forms the basis of nuclear power generation and nuclear weapons.
Uranium (Josh Dorman)
Uranium was discovered in 1789 in Germany by Martin Heinrich Klaproth, though Eugene Péligot isolated a pure sample in 1841. It is a naturally radioactive solid metal with various isotopes, but U-235 and U-238 are most common. Uranium has many uses including fuel for nuclear power plants, but depleted uranium used in armor and weapons can create dangerous radioactive dust upon impact.
More Related Content
What's hot
Radiocarbon dating
Radiocarbon dating is a method for determining the age of organic material by measuring the amount of radioactive carbon-14 remaining in the sample. Willard Libby developed the method in the 1940s, for which he won the Nobel Prize in 1960. It is based on the principle that living organisms absorb carbon-14 from the atmosphere, but after death, the amount of carbon-14 decreases as it radioactively decays. By measuring the amount of carbon-14 remaining and knowing its half-life of 5730 years, the age of the sample can be estimated. Radiocarbon dating has revolutionized understanding of chronologies in archaeology, geology, and other fields, but is limited to dating samples under 60,000 years
Paleontology, types & uses of fossils
Main Topic of Paleontology (Study of Fossils or remains of living organisms), Fossils and Types of Fossils & Significance of Fossils
Classification of micro fossil theory
Microscopic animal
Microscopic Algae
Bacteria
Microfossil of uncertain effinities
Microfossil elements of smaller animal
Microfossil fragments of larger organism
geochronolgy and age of earth
This document provides information about geochronology and dating the age of the Earth. It discusses how the Earth is estimated to be 4.6 billion years old based on dating of meteorites and the oldest Earth rocks. It describes the principles of relative dating methods like superposition and cross-cutting relationships. It also explains numerical dating techniques using radioactive isotopes like potassium-argon and uranium-lead dating to assign absolute ages to rocks in millions or billions of years. Finally, it briefly discusses isostatic adjustment and two hypotheses about isostasy proposed by J.H. Pratt and G.B. Airy.
Geological time scale
The document summarizes the geological time scale which divides Earth's history into different eras, periods, and epochs based on fossil and stratigraphic evidence. It describes the four eons of Earth's history starting with the Hadean and Archean eons of the earliest lifeforms like bacteria. It then outlines the major eras - Paleozoic, Mesozoic, and Cenozoic - describing some of the significant lifeforms, events, and environmental changes that occurred during each period within these eras. The largest unit of the geological time scale is the eon, while the smallest is the epoch.
Fossil ppt
This document discusses different types of fossils and fossilization. It describes fossils as remains or traces of once-living organisms found in rock. There are several modes of fossil preservation discussed, including entire body preservation, entire skeleton preservation, petrification and replacement, molds and casts, imprints, traces and trails, and burrows. The importance of fossils is also mentioned, such as for studying evolution, paleoecology, and paleogeography of ancient life.
U th-pb dating
U-Th-Pb dating involves the radioactive decay of uranium and thorium isotopes into lead isotopes. This method was first used in the early 20th century to determine the ages of rocks. It has since become the most precise dating technique. Uranium-238 decays to lead-206, uranium-235 decays to lead-207, and thorium-232 decays to lead-208. By measuring the ratios of these radioactive and stable lead isotopes to their uranium and thorium parents in a rock sample, its age can be calculated based on the known decay rates. The U-Pb dating method can be used to construct isochrons to obtain more accurate dates, though open system behavior can cause
Phylum mollusca
This document provides information about the phylum Mollusca. It focuses on one class within this phylum, the Bivalvia (Lamellibranchia). Key points:
- Bivalvia are aquatic molluscs enclosed within a calcareous bivalve shell. They lack a head and have gills (lamellae) for respiration.
- The shell consists of two valves joined by a hinge, which are covered internally by the mantle. The mantle forms an enclosed mantle cavity.
- Three main types of dentition exist in the hinge: taxodont, with many small teeth; heterodont, with different sized teeth; and desmodont, replacing teeth with
Classification of brachiopoda
1. The document discusses the classification of brachiopods, a phylum of marine invertebrates. It describes their two main classes, Articulata and Inarticulata, based on whether their shells have articulating features.
2. Within these classes are orders, superfamilies, and families classified by characteristics like shell structure, pedicle features, and internal structures. Over 12,000 fossil brachiopod species have been identified.
3. The classification system presented divides brachiopods into classes, orders, and superfamilies based on features like shell structure, pedicle morphology, and internal structures.
trilobites
The document discusses the phylum Arthropoda, specifically the class Trilobita. Trilobites had a three-lobed body plan divided into three sections - the cephalon (head), thorax (body), and pygidium (tail). Their dorsal surface was protected by a calcareous exoskeleton. Trilobites first appeared in the Lower Cambrian period and became extinct by the end of the Paleozoic era. They exhibited changes over time including a reduction in thoracic segments and variations in eye and glabella morphology.
MORPHOLOGY AND EVOLUTION TREND OF GASTROPOD
The document discusses the class Gastropoda, which includes snails, whelks, and limpets. It describes their morphology, anatomy, shell structures, forms, ornamentation, and evolutionary trends. Key points include: Gastropods have a coiled, spiral shell with an open anterior end called the aperture; their shells come in many forms depending on factors like spire angle and whorl size; and evolutionary trends have led to increased coiling, ornamentation loss, and aperture modification over time in both dextral and sinistral forms from the Triassic to present.
Mass extinction
This document outlines 5 major mass extinction events that have occurred throughout history, along with their estimated time periods, sizes, impacted species, and suspected causes. The largest was the Permian-Triassic extinction 251 million years ago, which led to 96% of species being eliminated. The most recent was the Cretaceous-Tertiary extinction 66 million years ago that wiped out the dinosaurs. Evidence points to large asteroid impacts as playing a role in the latter, while volcanic activity also likely contributed to several extinctions. The document concludes by noting we may be in the midst of a sixth mass extinction currently due to habitat loss and human impacts.
Stromatolites and its stratigraphic implications
This document summarizes the seminar content on stromatolites, including an introduction to stromatolites, their origin and evolution throughout geologic eras from Precambrian to Cenozoic. Key points covered include stromatolites being the oldest known fossil dating to over 3 billion years ago, their significance in changing Earth's early atmosphere, their dominance as the primary lifeform for over 2 billion years, and their increasing rarity today with some modern examples found in Shark Bay, Australia.
Radiometric dating
Radiometric dating uses the decay of radioactive isotopes like carbon-14 and potassium-40 to date rock layers. Radioactive isotopes break down at a steady rate, allowing scientists to measure the amount remaining in a rock to determine its age by comparing it to the original amount. Different isotopes have different half-lives, such as 1.3 billion years for potassium-40 and 5,730 years for carbon-14, enabling the dating of rocks from thousands to billions of years old.
Brachiopods
Brachiopods are marine invertebrates that live in oceans worldwide. They have two shells or valves and a coiled feeding organ called a lophophore. There are two major groups - articulate brachiopods which have teeth and sockets that join the valves, and inarticulate brachiopods which rely on muscles. Brachiopods have been around for over 500 million years and their fossils provide clues about ancient marine environments, though there are fewer living species today.
Evolution of elephant
Evolution is a developmental process from simple to complex form of life. Evolution of elephant started 60mya, from size of a pig. It spread all over world especially Africa and Asia. Today only two species Loxodonta and Elephas exist.
Morphology of ostracods
Ostracods are bivalved crustaceans that are commonly used in micropaleontology and paleoecology research. They have a complex morphology and are found in both marine and freshwater environments around the world. Key aspects of ostracod anatomy include their carapace, hinge patterns, and ornamentation, which are important for classifying and interpreting species. Ostracods first appeared in the late Cambrian and have adapted to occupy nearly all aquatic habitats, with over 2000 known living species today. Their fossil record allows them to be used for biostratigraphy and paleoenvironmental reconstruction.
The Geological Time Scale
The geologic time scale (GTS) is a system of chronological dating that relates geological strata (stratigraphy) to time. Geologists have divided Earth's history into a series of time intervals. These time intervals are not equal in length like the hours in a day. Instead the time intervals are variable in length. This is because geologic time is divided using significant events in the history of the Earth.
Foraminifera , micro fossil
Microfossils are very small remains of organisms 0.001 mm (1 micron) to 1 mm, that require magnification for study.
They are abundant, can be recovered from small samples.
Provide the main evidence for organic evolution through the time
They classified into two groups:
Organic-walled; Acritarchs, Dinoflagellate, Spores and Pollen grains … etc.
Foraminifera Each chamber interconnected by an opening (foramen) or several openings (foramina).
Known from Early Cambrian through to recent times, and has reached its acme during the Cenozoic.
Have a wide environmental range from terrestrial to deep sea and from polar to the tropical region.
Depending on the species, the shell may be made of organic compounds, sand grains and other particles cemented together, or from crystalline calcite.
Inorganic walled; Diatoms, Silicoflagellates, Ostracods, Conodonts, and Foraminifera
Paleomagnetism
Paleomagnetism is the study of ancient magnetic fields preserved in rocks. When rocks form, magnetic minerals within them align with the Earth's magnetic field at that time, recording its orientation. Studying the orientation of these magnetic minerals in rocks from different locations and time periods allows scientists to map changes in the Earth's magnetic field through time and reconstruct movements of tectonic plates. Paleomagnetism provides strong evidence for plate tectonic theory, showing that continents have moved over Earth's history by matching the magnetic signatures of separated landmasses and revealing symmetrical magnetic patterns on either side of mid-ocean ridges from sea floor spreading.
What's hot (20)
Similar to Uranium and uranium dating.pptx
Uranium And Nuclear Elements
Uranium-235 is a fissile isotope of uranium that can undergo nuclear fission when struck by a neutron. When a U-235 atom absorbs a neutron, it becomes Uranium-236 which is unstable and spontaneously splits into two smaller atoms, releasing additional neutrons and a large amount of energy. This fission reaction forms the basis of nuclear power generation and nuclear weapons.
Uranium (Josh Dorman)
Uranium was discovered in 1789 in Germany by Martin Heinrich Klaproth, though Eugene Péligot isolated a pure sample in 1841. It is a naturally radioactive solid metal with various isotopes, but U-235 and U-238 are most common. Uranium has many uses including fuel for nuclear power plants, but depleted uranium used in armor and weapons can create dangerous radioactive dust upon impact.
79035bb0 a6be-4cc1-8f52-b943b8d5af78 (1)
This document discusses various applications of radioactive isotopes. It begins by introducing radioisotope tracers and why they are ideal for tracking materials through complex processes. Only a small number of radioactive atoms are needed to be detectable. It then discusses specific applications such as medical uses of short-lived isotopes to image organs, using tracers to detect leaks, and radioactive dating methods like carbon-14 dating. The document concludes by mentioning radioisotope thermoelectric generators use radioactive decay to generate electricity and have been used to power spacecraft.
Surface Exposure Dating And its Application
Surface exposure dating is a collection of techniques used to estimate how long geological materials have been exposed at Earth's surface. It dates events like glacial advances, erosion history, lava flows, and meteorite impacts. There are two main methods: absolute dating provides accurate ages, while relative dating determines the sequence of events without specific dates. Examples of absolute techniques include radiocarbon dating, potassium-argon dating, and luminescence dating. Relative techniques include stratigraphy, seriation, and fluorine absorption dating. Surface exposure dating has applications for reconstructing glacial chronologies, shoreline changes, landscape development rates, and volcanic and archaeological timelines.
Uranium
Uranium is a radioactive element that is found in minerals in the Earth's crust. It has important industrial uses in nuclear power generation and was also used in the atomic bombs dropped on Hiroshima and Nagasaki. Uranium mining occurs around the world, with Kazakhstan being the largest producer. Prolonged exposure to uranium can increase cancer risks and cause kidney damage due to its radioactivity and toxicity.
Carbon dating
This document discusses carbon dating and its uses in determining the age of once-living materials. Carbon dating works by measuring the amount of carbon-14 remaining in organic material. It has a half-life of about 5,730 years and can date materials up to 60,000 years old. Examples given where carbon dating has been applied include dating the Dead Sea Scrolls to 250-130 BC, determining the Shroud of Turin originated in the 13th century, and estimating meteorite exposure times on Earth. Archaeology also relies heavily on radiocarbon dating.
Radimatric dating112121123121242342134125125.ppt
This document discusses radiometric dating techniques used to determine the absolute ages of rocks, minerals, and fossils. It explains that radioactive elements decay at consistent rates, allowing scientists to measure the proportions of parent and daughter isotopes to calculate age. Examples are given of potassium-argon dating, uranium-lead dating, and radiocarbon dating, along with their applicable time ranges. The production of carbon-14 in the atmosphere and its incorporation into living things is also summarized.
2 age of the earth
1) The oldest rocks on Earth are around 3.7-3.8 billion years old based on radiometric dating.
2) Even older zircon crystals around 4.0-4.2 billion years have been found embedded in younger rocks.
3) The best estimate for the age of the Earth itself comes from lead isotope dating of meteorites, yielding an age of 4.54 billion years.
Nit raipur
The document discusses different methods that were used to determine the age of the Earth prior to radiometric dating. These included estimating ages based on the history of organic evolution (1 billion years), the rate of sedimentation (500 million years), and the salinity of oceans (120 million years). It also describes how Lord Kelvin calculated the age to be between 20-40 million years based on the Earth's cooling rate. Modern radiometric dating methods, such as uranium-lead and potassium-argon dating, are now used and have determined the age of the Earth to be approximately 4600 million years.
Absolute Dating.pptx
This document discusses various absolute dating methods used in archaeology to determine the precise age of artifacts, fossils, and rocks in years. It describes radiocarbon dating, also known as carbon-14 dating, which determines the age of organic materials by measuring the radioactive decay of carbon-14. It also explains thermoluminescence dating to date pottery and other baked clay artifacts by measuring accumulated radiation, potassium-argon dating which dates volcanic rocks based on the decay of potassium-40 into argon gas, and dendrochronology which dates wood by comparing patterns of tree ring growth variations.
Nuclear Energy
The document discusses the history and properties of uranium and thorium as nuclear energy resources. It begins by stating that thorium has disadvantages compared to uranium for commercial use, as it is not as soluble and does not contain fissile material. It then discusses how uranium and thorium were formed in supernova explosions billions of years ago and have accumulated in the Earth's crust over time. The document also covers early natural nuclear reactors at Oklo, Gabon, properties of uranium that allow it to be concentrated, and the initial discoveries and concepts in the development of nuclear fission.
Determining Geologic Time Scale using Absolute and Relative Dating Earth Scie...
The document discusses methods for determining the geologic time scale and dating geological features. It describes the four eons the geologic time scale is divided into and explains both relative and absolute dating techniques. Relative dating looks at relationships between geological features, while absolute dating uses measurements of radioactive isotopes in rocks and minerals to calculate their precise ages. Examples provided include William Smith's work identifying distinctive fossil sequences to correlate rock layers and the potassium-argon dating method.
Earth Science 3.3 : Absolute Dating: A Measure of Time
Radiometric dating determines the age of objects by measuring the decay of radioactive isotopes into stable daughter isotopes. There are four main types of radiometric dating: 1) potassium-argon dating works on rocks over 100,000 years old, 2) uranium-lead dating dates rocks over 10 million years using uranium-238 decay, 3) rubidium-strontium dating also dates rocks over 10 million years, and 4) carbon-14 dating is used on objects under 50,000 years old by measuring carbon-14 decay. The rate of radioactive decay remains constant, allowing scientists to determine a sample's age based on the ratio of parent and daughter isotopes.
Each group should plot on graph paper the ½ life of the radioisotope.pdf
Each group should plot on graph paper the ½ life of the radioisotopes using the special graph
paper supplied by the teacher. The y-axis has a log scale and begins at 100% of the parent
radioisotope present; the next point is 100/ 2, or 50% parent radioisotope present; the next point
is 50/2, or 25%; and so on.). For example, if the ratio of C-14 to C-13 is 1:3 than the fossil is
how old? 5600 +5600. Correct? For each of the radioisotopes listed above, make a radiometric
graph going to 3 half-lives. Be sure to make one graph using uranium-lead and potassium-argon
dating to one half life. This will become useful later. Why?
Uranium-Lead dating method
Very careful measurements in laboratories, made on VERY LARGE numbers of U-235 atoms,
have shown that each of the atoms has a 50:50 chance of decaying during about 704,000,000
years. In other words, during 704 million years, half the U-235 atoms that existed at the
beginning of that time will decay to Pb-207. This is known as the half life of U- 235. Many
elements have some isotopes that are unstable, essentially because they have too many neutrons
to be balanced by the number of protons in the nucleus. Each of these unstable isotopes has its
own characteristic half life. Some half lives are several billion years long, and others are as short
as a ten-thousandth of a second.
The uranium-lead radiometric dating scheme has been refined to the point that the error margin
in dates of rocks can be as low as less than two million years in two-and-a-half billion years. An
error margin of 2–5% has been achieved on younger Mesozoic rocks.
One of its great advantages is that any sample provides two clocks, one based on uranium-235\'s
decay to lead-207 with a half-life of about 700 million years, and one based on uranium-238\'s
decay to lead-206 with a half-life of about 4.5 billion years, providing a built-in crosscheck that
allows accurate determination of the age of the sample even if some of the lead has been lost.
Potassium-argon dating method
This involves electron capture or positron decay of potassium-40 to argon-40. Potassium-40 has
a half-life of 1.3 billion years, and so this method is applicable to the oldest rocks. Radioactive
potassium-40 is common in micas, feldspars, and hornblendes, though the closure temperature is
fairly low in these materials, about 125°C (mica) to 450°C (hornblende).
#1-23 meters deep from top of hill (limestone)
#2-18 meters deep from top of hill (limestone/volcanic ash)
#3-34 meters deep from base of hill (sandstone)
#4-39 meters deep from top of hill (sandstone)
#5- 50 meters deep from bottom of hill (slate)
#6-26 meters deep (limestone)
#7-10 meters into hill (basalt)
#8-50 meters deep from base of hill (pegmatite)
#9- 3 meters deep into hill (erosion surface of limestone)
#10-52 meters deep from top of hill (pegmatite)
#11- on bank of stream (in shale)
#12- from base of hill 63 meters deep (in granite)
#13-47 meters deep from base of hill (pegmatite)
#14- 2 meters de.
Radioactive Isotopes
The document discusses the use of radioactive isotopes in geology and forensics. It describes the components of atoms, including protons, neutrons, and electrons. Isotopes are variants of the same element that differ in their number of neutrons. Unstable isotopes decay over time, while stable isotopes can be used for radiometric dating. Examples are given of carbon-14 dating of artifacts like the Dead Sea Scrolls and Stonehenge. Forensic cases show how carbon-14 has been used to date things like the Shroud of Turin and nuclear test fallout in teeth.
Earth History ppt
I believe that the more you know about the past, the better you are prepared for the future.
-Theodore roosevelt
Potassium Argon Dating ver 0.3
The document discusses radiometric dating techniques, specifically potassium-argon dating. It raises several assumptions and potential problems with potassium-argon dating, including uncertainties in determining initial ratios of parent-daughter isotopes, the possibility of leaching or contamination altering results, and examples of dates from rocks and lava of known ages producing dates that are too old. It suggests dating techniques may produce erroneous dates if key assumptions are violated and that dates are sometimes selectively interpreted or discarded if they don't match preconceived notions of age. Overall, the document casts doubt on the reliability of radiometric dating and its ability to accurately determine the ages of rocks.
Actinide series
The document discusses the actinide series of elements in the periodic table. It covers the properties and uses of actinium, thorium, protactinium, uranium, neptunium, plutonium, americium, and later actinides like curium. The actinide series includes radioactive elements with atomic numbers from 89 to 103. They have similar chemical properties and most exhibit oxidation states of +3 and +4. Many actinides are used as nuclear fuel or in specialized detection devices.
RADIOACTIVE DATING (U-Pb) 2.pptx
Geologists use radiometric dating techniques like uranium-lead dating to determine the age of rocks and fossils. Uranium-lead dating relies on the radioactive decay of uranium isotopes U-238 and U-235 into lead isotopes over millions to billions of years. The technique can date materials from 1 million to over 4.5 billion years old with high precision, but works best with minerals like zircon that fully retain the uranium and lead. While very accurate when applied properly, uranium-lead dating of zircon can sometimes produce confusing results requiring special treatment of the zircon samples.
Uranium final[1]
Uranium is a radioactive metal that was discovered in 1789. It has since been used to develop nuclear weapons and power, though it poses health risks if exposed. Key events include its discovery, uses in pottery and glass, Marie Curie's studies showing it is radioactive, the Manhattan Project developing the first nuclear bomb using uranium-235, and current uses in nuclear power and military applications. The document also outlines uranium's effects on human body systems and potential health issues from exposure.
Similar to Uranium and uranium dating.pptx (20)
Determining Geologic Time Scale using Absolute and Relative Dating Earth Scie...
Determining Geologic Time Scale using Absolute and Relative Dating Earth Scie...
Earth Science 3.3 : Absolute Dating: A Measure of Time
Earth Science 3.3 : Absolute Dating: A Measure of Time
Each group should plot on graph paper the ½ life of the radioisotope.pdf
Each group should plot on graph paper the ½ life of the radioisotope.pdf
More from Laraib Naeem
managment plan for ecosystem in KPk.pptx
Management plan for ecosystem in KPk
Ecosystem
component of ecosystem
The Biocenosis (Biotic)
The Biotope (Abiotic)
Examples/Types of Ecosystem
Functions of Ecosystem
Factors Affecting Ecosystem
How Ecosystem Changed?
Ecosystem Management
Why to Manage a Ecosystem?
Ecosystem Services?
Forest Management Practices
1.Timber Harvesting
2. Timber Thinning
Commercial timber thinning
Pre-commercial thinning
3. Prescribed Burning
uses and misuses of social media.pptx
Social media refers to virtual communities and networks where people interact and share information. Popular social media tools include Facebook, Twitter, Instagram, WhatsApp, and YouTube. The founders of these major sites include Mark Zuckerberg, Larry Page, Sergey Brin, and Elon Musk. While social media can cause addiction, reduced physical activity, and health issues, it also makes connecting with others easier, allows for quick sharing of information, and can benefit business strategies and education.
Social behavior and its types
Social behavior is defined as behavior among members of the same species where individuals affect one another through interaction. It benefits groups by providing protection from predators through safety in numbers and cooperative hunting. Well-developed social behavior is seen in insect societies like ants that live in large colonies with different individuals specialized in tasks like building, foraging, or protecting the colony. Types of social behavior include aggressive behavior used for defense, agonistic behavior where individuals threaten each other, parental behavior caring for offspring, and altruistic behavior where individuals sacrifice for the benefit of others like giving alarm calls to warn groups of crows.
DEAE-Dextran method.pptx
The DEAE-dextran method is a technique for transfection of nucleic acids into cultured mammalian cells. It involves mixing the nucleic acid with the cationic polymer DEAE-dextran to form complexes via electrostatic interactions. These complexes are added to cells and uptake is induced by osmotic shock, then the cells are washed and assayed for gene expression. The method is easy, low-cost, and can transfect a variety of cell types, but efficiency is lower than other techniques and high DEAE-dextran concentrations can be toxic.
Ayubia national park.pptx
Ayubia National Park is a protected area in Abbottabad, Pakistan declared a national park in 1984. It covers an area of 3,312 hectares and is surrounded by villages and towns. The park protects representative moist temperate forest and provides refuge for endangered species like the Asiatic leopard and black bear. Over 200 bird, 31 mammal, and other species inhabit the park. The park aims to conserve biodiversity and provides research and recreation opportunities. Tourism is an important part of the park with over 100,000 annual visitors enjoying hiking trails, picnic areas, and the chairlift.
Forest and its importance, Management and land uses.pdf
A Fantastic PPT about Forest and its types, importance of forests, management and its land uses. Explore it and get vast knowledge. Hope you like it!!
More from Laraib Naeem (6)
Forest and its importance, Management and land uses.pdf
Forest and its importance, Management and land uses.pdf
Recently uploaded
Methods of grain storage Structures in India.pdf
•Post-harvestlossesaccountforabout10%oftotalfoodgrainsduetounscientificstorage,insects,rodents,micro-organismsetc.,
•Totalfoodgrainproductioninindiais311milliontonnesandstorageis145mt.InIndia,annualstoragelosseshavebeenestimated14mtworthofRs.7,000croreinwhichinsectsaloneaccountfornearlyRs.1,300crores.
•InIndiaoutofthetotalproduction,about30%ismarketablesurplus
•Remaining70%isretainedandstoredbyfarmersforconsumption,seed,feed.Hence,growerneedstoragefacilitytoholdaportionofproducetosellwhenthemarketingpriceisfavourable
•TradersandCo-operativesatmarketcentresneedstoragestructurestoholdgrainswhenthetransportfacilityisinadequate
Compositions of iron-meteorite parent bodies constrainthe structure of the pr...
Magmatic iron-meteorite parent bodies are the earliest planetesimals in the Solar System,and they preserve information about conditions and planet-forming processes in thesolar nebula. In this study, we include comprehensive elemental compositions andfractional-crystallization modeling for iron meteorites from the cores of five differenti-ated asteroids from the inner Solar System. Together with previous results of metalliccores from the outer Solar System, we conclude that asteroidal cores from the outerSolar System have smaller sizes, elevated siderophile-element abundances, and simplercrystallization processes than those from the inner Solar System. These differences arerelated to the formation locations of the parent asteroids because the solar protoplane-tary disk varied in redox conditions, elemental distributions, and dynamics at differentheliocentric distances. Using highly siderophile-element data from iron meteorites, wereconstruct the distribution of calcium-aluminum-rich inclusions (CAIs) across theprotoplanetary disk within the first million years of Solar-System history. CAIs, the firstsolids to condense in the Solar System, formed close to the Sun. They were, however,concentrated within the outer disk and depleted within the inner disk. Future modelsof the structure and evolution of the protoplanetary disk should account for this dis-tribution pattern of CAIs.
11.1 Role of physical biological in deterioration of grains.pdf
Storagedeteriorationisanyformoflossinquantityandqualityofbio-materials.
Themajorcausesofdeteriorationinstorage
•Physical
•Biological
•Mechanical
•Chemical
Storageonlypreservesquality.Itneverimprovesquality.
Itisadvisabletostartstoragewithqualityfoodproduct.Productwithinitialpoorqualityquicklydepreciates
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...
Wereport the study of a huge optical intraday flare on 2021 November 12 at 2 a.m. UT in the blazar OJ287. In the binary black hole model, it is associated with an impact of the secondary black hole on the accretion disk of the primary. Our multifrequency observing campaign was set up to search for such a signature of the impact based on a prediction made 8 yr earlier. The first I-band results of the flare have already been reported by Kishore et al. (2024). Here we combine these data with our monitoring in the R-band. There is a big change in the R–I spectral index by 1.0 ±0.1 between the normal background and the flare, suggesting a new component of radiation. The polarization variation during the rise of the flare suggests the same. The limits on the source size place it most reasonably in the jet of the secondary BH. We then ask why we have not seen this phenomenon before. We show that OJ287 was never before observed with sufficient sensitivity on the night when the flare should have happened according to the binary model. We also study the probability that this flare is just an oversized example of intraday variability using the Krakow data set of intense monitoring between 2015 and 2023. We find that the occurrence of a flare of this size and rapidity is unlikely. In machine-readable Tables 1 and 2, we give the full orbit-linked historical light curve of OJ287 as well as the dense monitoring sample of Krakow.
The cost of acquiring information by natural selection
This is a short talk that I gave at the Banff International Research Station workshop on Modeling and Theory in Population Biology. The idea is to try to understand how the burden of natural selection relates to the amount of information that selection puts into the genome.
It's based on the first part of this research paper:
The cost of information acquisition by natural selection
Ryan Seamus McGee, Olivia Kosterlitz, Artem Kaznatcheev, Benjamin Kerr, Carl T. Bergstrom
bioRxiv 2022.07.02.498577; doi: https://doi.org/10.1101/2022.07.02.498577
Summary Of transcription and Translation.pdf
Hello Everyone Here We are Sharing You with The process of protien Synthesis in very short points you will be Able to understand It Very well
TOPIC OF DISCUSSION: CENTRIFUGATION SLIDESHARE.pptx
Centrifugation is a powerful technique used in laboratories to separate components of a heterogeneous mixture based on their density. This process utilizes centrifugal force to rapidly spin samples, causing denser particles to migrate outward more quickly than lighter ones. As a result, distinct layers form within the sample tube, allowing for easy isolation and purification of target substances.
Embracing Deep Variability For Reproducibility and Replicability
Embracing Deep Variability For Reproducibility and ReplicabilityUniversity of Rennes, INSA Rennes, Inria/IRISA, CNRS
Embracing Deep Variability For Reproducibility and Replicability
Abstract: Reproducibility (aka determinism in some cases) constitutes a fundamental aspect in various fields of computer science, such as floating-point computations in numerical analysis and simulation, concurrency models in parallelism, reproducible builds for third parties integration and packaging, and containerization for execution environments. These concepts, while pervasive across diverse concerns, often exhibit intricate inter-dependencies, making it challenging to achieve a comprehensive understanding. In this short and vision paper we delve into the application of software engineering techniques, specifically variability management, to systematically identify and explicit points of variability that may give rise to reproducibility issues (eg language, libraries, compiler, virtual machine, OS, environment variables, etc). The primary objectives are: i) gaining insights into the variability layers and their possible interactions, ii) capturing and documenting configurations for the sake of reproducibility, and iii) exploring diverse configurations to replicate, and hence validate and ensure the robustness of results. By adopting these methodologies, we aim to address the complexities associated with reproducibility and replicability in modern software systems and environments, facilitating a more comprehensive and nuanced perspective on these critical aspects.
https://hal.science/hal-04582287
JAMES WEBB STUDY THE MASSIVE BLACK HOLE SEEDS
The pathway(s) to seeding the massive black holes (MBHs) that exist at the heart of galaxies in the present and distant Universe remains an unsolved problem. Here we categorise, describe and quantitatively discuss the formation pathways of both light and heavy seeds. We emphasise that the most recent computational models suggest that rather than a bimodal-like mass spectrum between light and heavy seeds with light at one end and heavy at the other that instead a continuum exists. Light seeds being more ubiquitous and the heavier seeds becoming less and less abundant due the rarer environmental conditions required for their formation. We therefore examine the different mechanisms that give rise to different seed mass spectrums. We show how and why the mechanisms that produce the heaviest seeds are also among the rarest events in the Universe and are hence extremely unlikely to be the seeds for the vast majority of the MBH population. We quantify, within the limits of the current large uncertainties in the seeding processes, the expected number densities of the seed mass spectrum. We argue that light seeds must be at least 103 to 105 times more numerous than heavy seeds to explain the MBH population as a whole. Based on our current understanding of the seed population this makes heavy seeds (Mseed > 103 M⊙) a significantly more likely pathway given that heavy seeds have an abundance pattern than is close to and likely in excess of 10−4 compared to light seeds. Finally, we examine the current state-of-the-art in numerical calculations and recent observations and plot a path forward for near-future advances in both domains.
Male reproduction physiology by Suyash Garg .pptx
Physiology of Male reproduction.
Video mentioned at page no. 23 as summary for better understanding
Anti-Universe And Emergent Gravity and the Dark Universe
Recent theoretical progress indicates that spacetime and gravity emerge together from the entanglement structure of an underlying microscopic theory. These ideas are best understood in Anti-de Sitter space, where they rely on the area law for entanglement entropy. The extension to de Sitter space requires taking into account the entropy and temperature associated with the cosmological horizon. Using insights from string theory, black hole physics and quantum information theory we argue that the positive dark energy leads to a thermal volume law contribution to the entropy that overtakes the area law precisely at the cosmological horizon. Due to the competition between area and volume law entanglement the microscopic de Sitter states do not thermalise at sub-Hubble scales: they exhibit memory effects in the form of an entropy displacement caused by matter. The emergent laws of gravity contain an additional ‘dark’ gravitational force describing the ‘elastic’ response due to the entropy displacement. We derive an estimate of the strength of this extra force in terms of the baryonic mass, Newton’s constant and the Hubble acceleration scale a0 = cH0, and provide evidence for the fact that this additional ‘dark gravity force’ explains the observed phenomena in galaxies and clusters currently attributed to dark matter.
Farming systems analysis: what have we learnt?.pptx
Presentation given at the official farewell of Prof Ken Gillet at Wageningen on 13 June 2024
fermented food science of sauerkraut.pptx
This ppt contains the production of a fermented food name - sauerkraut
Recently uploaded (20)
Clinical periodontology and implant dentistry 2003.pdf
Clinical periodontology and implant dentistry 2003.pdf
Compositions of iron-meteorite parent bodies constrainthe structure of the pr...
Compositions of iron-meteorite parent bodies constrainthe structure of the pr...
11.1 Role of physical biological in deterioration of grains.pdf
11.1 Role of physical biological in deterioration of grains.pdf
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...
The cost of acquiring information by natural selection
The cost of acquiring information by natural selection
TOPIC OF DISCUSSION: CENTRIFUGATION SLIDESHARE.pptx
TOPIC OF DISCUSSION: CENTRIFUGATION SLIDESHARE.pptx
Embracing Deep Variability For Reproducibility and Replicability
Embracing Deep Variability For Reproducibility and Replicability
Microbiology of Central Nervous System INFECTIONS.pdf
Microbiology of Central Nervous System INFECTIONS.pdf
Anti-Universe And Emergent Gravity and the Dark Universe
Anti-Universe And Emergent Gravity and the Dark Universe
Farming systems analysis: what have we learnt?.pptx
Farming systems analysis: what have we learnt?.pptx
Uranium and uranium dating.pptx
- 2. Uranium “Uranium is a heavy, silver-grey, radioactive metal, used mainly in producing nuclear energy.” It is a silvery-grey metal in the actinide series(14 in No -atomic numbers 89 and 103) of the periodic table. A uranium atom has 92 protons and 92 electrons. Melting point of Uranium is 1132°C. Boiling point of Uranium is 3818°C. 2
- 3. 3
- 4. 4 Uranium was discovered in 1789 by a German Chemist Martin Klaproth. He named his discovery “uran” after the planet Uranus. History
- 5. Physical Properties 5 It is the most common heavy element in the Earth’s crust. Uranium is a hard, dense, malleable, ductile, radioactive metal. It is a poor conductor of heat and electricity.
- 6. 6 Occurrence Traces of it occur almost everywhere. It is more abundant than gold, silver or mercury. The Earth's crust from surface to 25 km down contains 100 trillion tons of Uranium, and the ocean contains 10 billion. Uranium was formed over 6.6 billion years ago. Uranium occurs naturally in the Earth's crust, water, air, and living organisms, Rocks (igneous, metamorphic or sedimentary rocks).
- 7. 7
- 8. 8 The rocks of Siwaliks of the Potwar Plateau, Northern Pakistan. Bannu Basin Dera Ghazi Khan Issa Khel and Kirther Range Suleiman range up to the Arabian Sea in the west have been extensively explored for uranium. ballistic missiles: the short-range Abdali (Hatf-2), Ghaznavi (Hatf-3), Shaheen-I (Hatf-4), and NASR (Hatf-9), and the medium-range Ghauri (Hatf-5) and Shaheen-II (Hatf-6).
- 9. Uranium Dating 9 A method of dating archaeological or geological specimens by determining the decay activity of the uranium in a given sample. Uranium dating is the oldest method of isotopic dating in which we can determine the age of organic materials using the radioactive chemical element Uranium. There are three different types of this technique: Uranium-Uranium method Uranium-Thorium method Uranium-Lead method. Among them, Uranium- lead method is the oldest method. But, it gives the most accurate results though it has a high risk.
- 10. 10 Methods of Uranium Dating Uranium- Uranium Method Uranium- Thorium Method Uranium- Lead Method
- 11. 11 1. Uranium-Uranium Method It is one of several radiometric dating techniques exploiting the Uranium radioactive decay series, in which 238U undergoes 14 alpha and beta decay events on the way to the stable isotope 206 Pb. Other dating techniques using this decay series include Uranium- thorium dating and Uranium- lead dating.
- 12. 12
- 13. 13 2. Uranium-Thorium Method A relatively short-range dating technique is based on the decay of uranium- 234 into thorium-230, a substance with a half-life of about 80,000 years. It is accompanied by a sister process, in which uranium-235 decays into protactinium-231, which has a half-life of 32,760 years. While uranium is water-soluble, thorium and protactinium are not, and so they are selectively precipitated into ocean-floor sediments, from which their ratios are measured.
- 14. 14 3. Uranium-Lead Method Uranium-238 is a radioactive isotope that decays in a series of steps to lead-206.The half-life of uranium-238 is 4.5 billion years. The decay series ends with lead-206, which is stable. The older the rock is, the more daughter material (lead-206) there will be in the rock. Uranium-lead dating can be used for rocks more than 10 million years old. Younger rocks do not contain enough daughter material to be accurately measured by this method.
- 15. 15
- 16. 16
- 17. 17 Uses of Uranium Dating Uranium–lead dating, abbreviated U–Pb dating, is one of the oldest and most refined of the radiometric dating schemes. It can be used to date rocks that formed and crystallized from about 1 million years to over 4.5 billion years. A Canadian research team has used a new uranium-lead (U-Pb) dating technique to show that a fossilised dinosaur bone found in New Mexico is only 64.8 million years old, meaning the creature was alive about 700,000 years after the mass extinction event that is believed to have wiped out all non-avian dinosaurs.
- 18. 18 Uranium-238 _ Uranium-238 dating, method of age determination that makes use of the radioactive decay of uranium-238 to uranium-234; the method can be used for dating of sediments from either a marine or a playa lake environment. Uranium decays through a number of radioactive daughter isotopes, some of which have half-lives comparable to the time scale of prehistoric archaeology. The growth of these isotopes in naturally occurring materials at archaeological sites can be used to determine the age of sites. Uranium–lead (U-Pb) dating: Measures the ratio of two lead isotopes (Pb-206 and Pb-207) to the amount of uranium in a mineral or rock. Uranium–thorium (U-Th) dating: This technique is used to date speleothems, corals, carbonates, and fossil bones. Its range is from a few years to about 700,000 years.
- 19. 19
- 20. 20