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Chapter 7: Determining Time in Prehistory True/False Questions 1) Relative dating establishes the exact chronological relationship between two artifacts found in the same context. Answer: False Rationale: Relative dating provides an order of events without determining the exact age. It establishes sequences or relative chronologies, but does not pinpoint specific calendar dates. 2) The use of index fossils is a kind of absolute dating technique. Answer: False Rationale: Index fossils are used in relative dating, not absolute dating. They are fossils of organisms that lived for a relatively short period, widely distributed geographically, and can be used to correlate and date the strata in which they are found. 3) The process of archaeological seriation depends on the existence of cultural change. Answer: True Rationale: Archaeological seriation relies on changes in artifact styles over time. It assumes that cultural styles change through time, allowing archaeologists to arrange artifacts into chronological sequences. 4) Both projectile points and pottery shards can be used as temporal types. Answer: True Rationale: Projectile points and pottery shards are examples of artifacts that can be used to establish relative chronologies. Their styles and typologies can change over time, allowing archaeologists to date the contexts in which they are found. 5) The three age system is an example of relative dating. Answer: True Rationale: The three-age system (Stone Age, Bronze Age, Iron Age) is a relative dating scheme that categorizes archaeological periods based on the predominant materials used for toolmaking and technological development. 6) Iron tools can be directly dated by extracting carbon introduced to the metal alloy during forging. Answer: True Rationale: Iron tools can be dated using radiocarbon dating if they contain carbon, which can be absorbed during the forging process. However, the method is limited by the carbon content and the potential for contamination. 7) Absolute dates are never reported with a significant error factor included. Answer: False Rationale: Absolute dates are often reported with an associated error margin, reflecting the uncertainty inherent in dating methods. This margin accounts for variables such as calibration, sample contamination, and statistical variations. 8) Since the advent of radiocarbon dating, FUN analysis has been used more frequently. Answer: False Rationale: There is no known archaeological dating technique referred to as "FUN analysis." Radiocarbon dating has indeed been widely used since its development, but the statement about FUN analysis is inaccurate. 9) Dendrochronology can be used at any site. Answer: False Rationale: Dendrochronology, or tree-ring dating, relies on the presence of well-preserved, datable wood samples. It can only be used in regions where trees have annual growth rings and where preserved wooden artifacts or structural remains are available. 10) As an archaeological dating technique, dendrochronology was first used on ancient wood beams in Europe. Answer: False Rationale: Dendrochronology was indeed developed in Europe, but its first applications were not limited to ancient wood beams. It has been used on various types of wooden artifacts and structures, including furniture, archaeological timbers, and tree-ring sequences from living trees. 11) The concentration of C-14 on earth has remained the same over time. Answer: False Rationale: The concentration of C-14 in the atmosphere has not remained constant over time due to factors such as fluctuations in solar activity and changes in Earth's magnetic field. This variation can lead to inaccuracies in radiocarbon dating. 12) The most commonly used and most important method of radiometric dating in archaeology is radiocarbon dating. Answer: True Rationale: Radiocarbon dating is widely used in archaeology for dating organic materials up to around 50,000 years old. It is a crucial method for establishing chronologies and understanding the timing of past events. 13) When an organism dies, it ceases to take in additional radiocarbon. Answer: True Rationale: After death, an organism no longer consumes carbon through respiration or ingestion. As a result, the carbon-14 (C-14) within its tissues begins to decay at a predictable rate, allowing for radiocarbon dating of organic remains. 14) Willard Libby formulated the Law of Superposition. Answer: False Rationale: The Law of Superposition was formulated by Nicolaus Steno in the 17th century. Willard Libby developed the technique of radiocarbon dating in the 1940s, for which he was awarded the Nobel Prize in Chemistry. 15) Before processing, radiocarbon samples are converted into carbon dioxide gas. Answer: True Rationale: Radiocarbon samples are typically converted into carbon dioxide gas through combustion or chemical processes before analysis. This ensures that the carbon being measured is in a form suitable for radiocarbon dating techniques. 16) The most common technique for assessing radiocarbon age is known as decay counting. Answer: True Rationale: Decay counting, also known as beta counting, is the most common method used to determine the radiocarbon age of a sample. It involves measuring the rate of decay of radioactive carbon-14 isotopes present in the sample. 17) At Olduvai Gorge, potassium-argon dating was used to date the eruption of the Olduvai volcano. Answer: True Rationale: Potassium-argon dating is a radiometric dating method used to determine the age of rocks, particularly volcanic rocks. It was used at Olduvai Gorge to date volcanic eruptions, providing valuable chronological information for archaeological sites in the area. 18) Isotopic uranium can be used to determine when cave limestone was deposited. Answer: True Rationale: Uranium-series dating is a radiometric dating method used to determine the age of calcium carbonate deposits, such as cave formations and speleothems. By measuring the radioactive decay of isotopic uranium within the deposits, scientists can estimate their age. 19) Thermoluminescence is a radiometric technique commonly used to date pottery, burned clay features, and cave formations ranging from 50 to 50,000 years in age. Answer: True Rationale: Thermoluminescence dating is commonly used to date materials containing crystalline minerals, such as pottery, burned clay, and certain types of sediment. It can provide age estimates ranging from a few decades to hundreds of thousands of years. 20) Electronic spin resonance is both more common and more accurate than thermoluminescence. Answer: False Rationale: While electronic spin resonance is another dating technique used for dating tooth enamel and quartz grains, it is not more common or necessarily more accurate than thermoluminescence. The choice of dating method depends on factors such as the type of sample and the age range being investigated. Multiple-Choice Questions 1) Which of the following is an example of a relative dating technique? A) seriation B) radiocarbon C) obsidian hydration D) potassium argon. E) dendrochronology Answer: A Rationale: Relative dating techniques, such as seriation, do not provide an exact age but establish the chronological order of artifacts or events based on their similarities or differences in style or form. 2) Australopithecus fossils were relatively dated through the use of __________. A) antelope fossils. B) dinosaur fossils. C) pig fossils. D) sloth fossils. E) monkey fossils. Answer: C Rationale: Relative dating methods, such as comparing the relative ages of fossils found in the same strata, were used to relatively date Australopithecus fossils by examining the associated pig fossils. 3) Which of the following is a relative dating method? A) cross-dating. B) dendrochronology. C) index fossils. D) radiocarbon dating. E) obsidian hydration. Answer: C Rationale: Index fossils, which are fossils of organisms that were widespread geographically and existed for a relatively short period, are used as indicators of the age of the strata in which they are found, making them a relative dating method. 4) Using evolutionary changes in well-known groups of animals as a dating tool is known as __________. A) faunal correlation. B) FUN dating C) cross referencing D) seriation E) dendrochronology Answer: D Rationale: Seriation involves arranging artifacts or fossils based on their evolving styles or characteristics, allowing archaeologists to establish relative chronological sequences. 5) The example of Greek coins in the text illustrates the utility of __________. A) seriation. B) stratigraphy. C) maritime archaeology. D) index fossils. E) radiocarbon dating Answer: A Rationale: Seriation involves arranging artifacts, such as coins, in chronological order based on their stylistic or typological similarities and differences, thus helping to establish relative dates. 6) FUN dating is based on the fact that the longer bone is buried in the ground, __________. A) the more fun it has. B) the more nitrogen it loses. C) the more nitrogen it absorbs. D) the less mass it has. E) the more it decays. Answer: B Rationale: FUN dating is based on the principle that bones buried in the ground lose nitrogen over time due to the decay process, allowing for the estimation of relative ages based on the extent of nitrogen loss. 7) The use of certain projectile point types or decorated pottery shards to date surface sites is an example of __________. A) functional types. B) seriation. C) temporal types. D) index fossils. E) FUN dating. Answer: C Rationale: Temporal types, such as specific projectile point types or pottery styles, are used to establish relative chronologies at surface sites based on the presence or absence of particular artifact types. 8) Dendrochronology __________. A) is less accurate than radiocarbon dating. B) can be used on any site. C) can only be used in very cold climates. D) requires a comparative collection. E) is only possible with petrified wood. Answer: D Rationale: Dendrochronology, or tree-ring dating, requires a comparative collection of tree-ring sequences to establish chronological patterns. It can be applied in various climates, not just cold ones, and is typically more accurate than radiocarbon dating for certain time periods. 9) Preparation of radiocarbon samples for analysis involves __________. A) adding contaminants. B) boiling the sample in a weak basic solution. C) boiling the sample in a weak acid solution. D) removing contaminants. Answer: D Rationale: Preparation of radiocarbon samples for analysis involves removing contaminants that may affect the accuracy of the radiocarbon dating results. 10) Radiocarbon data was originally referred to as __________. A) the Libby Curve of Knowns. B) the Lyell Chart of Ages. C) the Libby Graph of Dates. D) Taylor’s Carbon Dates. E) Taylor’s Radioactive Chart. Answer: A Rationale: Radiocarbon data was originally referred to as the Libby Curve of Knowns, named after Willard Libby, who developed the radiocarbon dating method. 11) The most commonly used and most important method of radiometric dating in archaeology is __________. A) radiocarbon dating. B) potassium-argon. C) uranium series. D) electron-spin resonance. E) fission track. Answer: A Rationale: Radiocarbon dating is widely used in archaeology for dating organic materials up to around 50,000 years old, making it one of the most important methods for establishing chronologies. 12) The half-life of radiocarbon is known to be approximately __________. A) 57,000 years. B) 5,700 years. C) 7,000 years. D) 57 years. E) 5,000 years. Answer: B Rationale: The half-life of radiocarbon, which is the time it takes for half of the radioactive carbon-14 to decay, is approximately 5,700 years. 13) Radiocarbon dating is accurate for dates ranging __________. A) from 100 to 100,000 years ago B) from 50,000 to 1.5 million years ago. C) from 300 to 50,000 years ago. D) from 50 to 3,000 years ago. E) none of the above Answer: C Rationale: Radiocarbon dating is accurate for dates ranging from approximately 300 to 50,000 years ago, making it suitable for dating a wide range of archaeological materials. 14) Liquid scintillation decay counting is a form of __________. A) seriation. B) radiocarbon dating. C) FUN analysis. D) thermoluminescence. E) obsidian hydration. Answer: B Rationale: Liquid scintillation decay counting is a technique used in radiocarbon dating to measure the decay of radioactive carbon-14 atoms in a sample. 15) Radiocarbon dating which involves atom counting __________. A) is called accelerator mass spectrometry dating. B) requires a larger sample than gas decay counting. C) involves a direct count of N14 atoms. D) can be used in every situation Answer: A Rationale: Radiocarbon dating that involves atom counting is called accelerator mass spectrometry dating, which allows for the measurement of the ratio of carbon-14 to carbon-12 atoms in a sample. 16) __________ is best dated using the potassium-argon method. A) Volcanic rock B) Fired clay C) Bone D) Shell E) Metal Answer: A Rationale: The potassium-argon method is best suited for dating volcanic rock, as it measures the decay of potassium-40 isotopes to argon-40 in minerals within the rock. 17) Fission-track dating can be applied to __________. A) volcanic rock. B) ancient natural glass. C) crystalline minerals found in ceramic artifacts. D) sedimentary rock Answer: C Rationale: Fission-track dating is applied to crystalline minerals, such as those found in ceramic artifacts, by measuring the density of tracks produced by the spontaneous fission of uranium-238 isotopes. 18) Which of the following would be dated best with thermoluminescence? A) bone. B) shell. C) wood. D) pottery. E) charcoal. Answer: D Rationale: Thermoluminescence dating is best suited for dating pottery, as it measures the accumulated radiation dose in minerals, such as quartz or feldspar, which resets to zero when the pottery is heated. 19) The most useful method of absolute dating for burnt clay house floors would be __________. A) potassium-argon. B) uranium series. C) radiocarbon dating. D) archaeomagnetism. E) obsidian hydration. Answer: D Rationale: Archaeomagnetism is the most useful method for dating burnt clay house floors, as it relies on the measurement of the Earth's magnetic field recorded in the burnt clay, providing a date range based on known changes in the Earth's magnetic field over time. 20) Obsidian hydration analysis provides estimates of __________. A) when the obsidian was formed. B) when tools made of the glassy stone were made. C) when a volcano erupted. D) where the obsidian was formed. E) all of the above. Answer: B Rationale: Obsidian hydration analysis provides estimates of when tools made of obsidian were made by measuring the thickness of the hydration layer formed on the surface of the obsidian artifact since its manufacture. 21) dating is based on measurements produced when archaeological materials are subjected to microwaves. A) Radiocarbon B) Thermoluminescence C) Electron spin resonance D) Potassium-argon E) Fission-track Answer: C Rationale: Electron spin resonance dating is based on the principle that trapped electrons within crystalline structures, when subjected to microwaves, emit electromagnetic radiation that can be measured to determine the age of the material. 22) Archaeomagnetism dates objects and events __________. A) by measuring their magnetism. B) by measuring their resistivity. C) by measuring their levels of radioactivity. D) by linking them to known-age shifts in Earth’s magnetic poles. Answer: D Rationale: Archaeomagnetism dates objects and events by linking them to known-age shifts in Earth’s magnetic poles, providing a relative dating method based on changes in the Earth's magnetic field over time. 23) Obsidian hydration dating is based on the fact that __________. A) obsidian absorbs water from the surrounding environment over time. B) obsidian loses water over time. C) obsidian absorbs nitrogen over time. D) obsidian changes color over time. Answer: A Rationale: Obsidian hydration dating is based on the principle that obsidian absorbs water from the surrounding environment over time, forming a hydration layer on its surface whose thickness can be measured to estimate the age of the artifact. Short Answer Questions 1) What is archaeometry? Answer: Archaeometry is the application of scientific methods and techniques to archaeological research, including the analysis of archaeological materials such as artifacts, ecofacts, and features using various scientific disciplines like chemistry, physics, and biology. 2) Why are seriation frequency curves often referred to as ʺbattleshipʺ curves? Answer: Seriation frequency curves are often referred to as "battleship" curves because they resemble the silhouette of a battleship, with a long, flat portion followed by a sudden drop. This shape reflects the frequency distribution of artifact types over time, with some types being common across many time periods (the long flat portion) and others being specific to only one or a few time periods (the sudden drop). 3) What are temporal types? Answer: Temporal types are artifact types that are characteristic of specific time periods. They are used in seriation and other relative dating methods to establish the chronological sequence of archaeological assemblages. 4) What is the difference between context-based and frequency-based seriation? Answer: Context-based seriation arranges artifacts based on the presence or absence of specific artifact types within archaeological contexts, such as strata or layers. Frequency-based seriation, on the other hand, relies on the relative frequencies of artifact types across multiple assemblages to establish their chronological order. 5) What role did FUN dating play in the Piltdown matter? Answer: FUN dating, which was based on the fluorine content of bones, played a crucial role in exposing the Piltdown hoax. Analysis using FUN dating revealed that the purportedly ancient human remains found at Piltdown had a modern fluorine content, indicating they were of recent origin and not as ancient as initially claimed. This helped to reveal the Piltdown Man as a forgery. 6) What are the five assumptions that underlie the use of radiocarbon dating? Answer: The five assumptions underlying radiocarbon dating are: 1. Constant production rate: The rate of production of radiocarbon in the atmosphere has remained constant over time. 2. Equilibrium in the atmosphere: The ratio of radiocarbon to stable carbon in the atmosphere is in equilibrium and remains constant. 3. Constant intake rate: Organisms take in carbon from the atmosphere at a constant rate through respiration, photosynthesis, or consumption of other organisms. 4. Constant decay rate: The rate of decay of radiocarbon isotopes in organic material is constant over time. 5. Closed system: The sample being dated is a closed system, meaning no carbon exchange occurs with the environment after the organism dies. 7) How does radiocarbon form? Answer: Radiocarbon (carbon-14) forms in the upper atmosphere when cosmic rays bombard nitrogen atoms, causing them to convert into carbon-14 isotopes. These carbon-14 isotopes combine with oxygen to form carbon dioxide, which is then absorbed by plants during photosynthesis. Animals then consume these plants, incorporating carbon-14 into their tissues. 8) What is a radiometric clock and how is it ʺsetʺ? Answer: A radiometric clock is a method of dating geological or archaeological materials based on the decay of radioactive isotopes. The "setting" of a radiometric clock refers to the initial condition of the system at the time of formation or deposition. This initial condition is determined by measuring the ratio of parent isotopes to daughter isotopes in the sample, providing a starting point for calculating the age of the material. 9) What must an archaeologist consider when collecting radiocarbon samples? Answer: When collecting radiocarbon samples, an archaeologist must consider several factors, including: • The type of material being sampled: Different materials (e.g., bone, charcoal, shell) have different carbon reservoir effects and may require different pretreatment methods. • Contamination risks: Care must be taken to avoid contamination from modern carbon sources during sample collection, handling, and processing. • Sample size: Sufficient material must be collected to yield a measurable amount of radiocarbon, but sampling should be minimized to preserve the archaeological context. • Stratigraphic context: Samples should be collected from well-stratified contexts to ensure accurate dating and interpretation. 10) What does obsidian hydration measure, and how can it be used to date archaeological materials? Answer: Obsidian hydration dating measures the penetration of water molecules into the surface of obsidian artifacts over time. As obsidian absorbs water, it forms a hydration rim whose thickness increases with exposure to moisture. By measuring the thickness of the hydration rim using microscopy or other techniques, archaeologists can estimate the age of the artifact. This method is particularly useful for dating relatively recent archaeological materials, such as prehistoric tools made from obsidian, within the last several tens of thousands of years. Essay Questions 1) Using examples from the text, describe how archaeologists use temporal types in constructing chronologies. Answer: Temporal types, such as pottery styles, projectile point designs, or architectural features, serve as diagnostic artifacts that are indicative of specific time periods. Archaeologists use these temporal types to establish relative chronologies by observing the presence or absence of certain types across different contexts. For example, in the Southwest United States, the presence of distinctive pottery types like Mesa Verde Black-on-white or Tularosa Black-on-white can help archaeologists date sites to particular periods. By analyzing the distribution of these temporal types across various sites, archaeologists can construct relative chronologies and identify patterns of cultural change over time. 2) List four types of relative dating methods. Describe the benefits and drawbacks of each and give an example of a context that would be useful for each type. Answer: a) Stratigraphy: Benefits include its reliance on the principle of superposition, where older layers are typically found beneath younger layers, allowing for a relative dating sequence. Drawbacks include complexities arising from disturbances such as bioturbation or post-depositional processes. Example: Examining the layers of sediment in an archaeological site. b) Seriation: Benefits include the ability to order artifacts based on their stylistic similarities and differences, providing relative chronological sequences. Drawbacks include the need for a large sample size and the assumption of cultural change. Example: Analyzing changes in pottery styles over time. c) Typological sequences: Benefits include the establishment of relative chronological sequences based on artifact typologies. Drawbacks include the potential for typologies to be subjective and the need for a robust comparative database. Example: Creating a sequence of projectile point types found in different archaeological contexts. d) Cross-dating: Benefits include the ability to correlate sequences from different sites or regions using shared temporal markers. Drawbacks include challenges in identifying reliable cross-dating indicators. Example: Matching tree-ring sequences from overlapping tree samples found in different archaeological contexts. 3) In examining the archaeology of the Great Basin, describe how archaeologists utilized vertical distribution of artifacts to make inferences about the temporal framework of that region. Back up your answer with examples from your textbook. Answer: In the Great Basin region, archaeologists utilized the vertical distribution of artifacts within stratigraphic layers to infer the temporal framework of archaeological sites. By observing the relative position of artifacts in stratigraphic profiles, researchers can make inferences about the relative ages of different cultural deposits. For example, in "Archaeology of the Great Basin" by Catherine Fowler, the vertical distribution of projectile points and pottery types at the Hidden Cave site in Nevada was used to identify distinct occupation phases spanning thousands of years. The deeper layers contained Desert Side-notched points associated with early Archaic occupations, while upper layers contained Elko series points indicative of later Archaic occupations. This vertical distribution of artifacts allowed archaeologists to establish a relative chronology for the site and interpret cultural changes over time. 4) Describe the preparation of radiocarbon samples for analysis. Answer: The preparation of radiocarbon samples for analysis involves several steps to ensure accurate and reliable results. First, archaeologists collect organic materials suitable for radiocarbon dating, such as charcoal, bone, or plant remains, from archaeological sites. The samples are then carefully cleaned to remove any contaminants, such as modern carbon or residues from preservation treatments. Next, the samples are pretreated to isolate the carbon fraction of interest. This may involve chemical treatments, such as acid or alkali washes, to remove carbonates or humic acids. After pretreatment, the samples are converted into a suitable form for radiocarbon analysis, typically graphite or CO2 gas. Finally, the radiocarbon samples are analyzed using accelerator mass spectrometry (AMS) or liquid scintillation counting to measure the ratio of radiocarbon to stable carbon isotopes. Proper sample preparation is critical to obtaining accurate radiocarbon dates and minimizing contamination. 5) What is the Shroud of Turin? How does the case of the Shroud of Turin illustrate the important contributions of absolute dating techniques to archaeology? Answer: The Shroud of Turin is a linen cloth purported to be the burial shroud of Jesus Christ, bearing the image of a man with wounds consistent with crucifixion. The case of the Shroud of Turin illustrates the important contributions of absolute dating techniques to archaeology by highlighting the need for scientifically rigorous dating methods to authenticate archaeological artifacts. In 1988, the Shroud was subjected to radiocarbon dating, which produced an estimated date range of AD 1260-1390, placing its origin in the medieval period rather than the time of Jesus. This radiocarbon dating analysis provided critical evidence for assessing the authenticity of the Shroud and debunking claims of its ancient origin based on historical or religious narratives alone. The case of the Shroud of Turin underscores the value of absolute dating techniques in resolving questions of authenticity and establishing reliable chronological frameworks for archaeological artifacts. Test Bank for Archaeology : The Science of the Human Past Mark Q. Sutton 9780205895311
