reading quiz 13/12

The continents that made up Pangaea came together in the early Paleozoic but began to split apart during the

Late Triassic/Early Jurassic.

Which of the following lists the four time divisions in order from oldest to youngest?

Proterozoic, Paleozoic, Mesozoic, Cenozoic

Geologists base their estimate that the Earth is 4.56 billion years old on

. isotopic dating of meteorites thought to be from primitive solids of the early Solar System.

Charcoal (burned wood) that was used to make prehistoric drawings on cave walls in France was scraped off and analyzed. The results showed 4 mg carbon-14 (parent isotope) and 60 mg nitrogen-14 (daughter isotope). The half-life of carbon-14 is 5,730 years. How old are the cave drawings?

22,920 years

A radioactive isotope of the element potassium decays to produce argon. If the ratio of argon to potassium is found to be 7:1, how many half-lives have occurred?

A. 3 half-lives

Identify the true statement. A. Multiple orogenies over time create great mountain ranges; the Taconic, Acadian, and Alleghanian orogenies produced the Appalachians. B. We currently live in the Holocene, which is a glacial time interval that began 11,000 years ago. C. A 1950s experiment with methane, ammonia, and oxygen suggested that life originated in warm pools of surface water. D. Atmospheric oxygen and nitrogen react to form the nitrogen oxide that protects land life from harmful ultraviolet rays.

A. Multiple orogenies over time create great mountain ranges; the Taconic, Acadian, and Alleghanian orogenies produced the Appalachians.

Which geologic time interval saw the first continents, the first life, and possibly the first plates?

Archean

Identify the true statement.A. Organisms with oxygen-based (aerobic) metabolism cannot produce energy efficiently, so they evolve smaller bodies than anaerobic organisms have. B. Shells on eggs keep them from drying out, so the eggs and the mother aren't tied to a water environment. C. When climate warms, sea level goes down because of increased evaporation. D. During the Mesozoic, North and South America became joined by the Isthmus of Panama, creating a land bridge between the two continents.

B. Shells on eggs keep them from drying out, so the eggs and the mother aren't tied to a water environment.

Identify the statement that is true about William Smith's observations. A. They led to the principle of cross-cutting relations. B. They revealed that groups of fossil species (fossil assemblages) occurred in limited intervals of strata. C. His observations of igneous intrusions in the English countryside helped develop the coal industry. D. Smith noted that a fossil species could disappear and then reappear in much younger strata.

B. They revealed that groups of fossil species (fossil assemblages) occurred in limited intervals of strata.

The principle of original continuity says that

B. sedimentary layers began as continuous expanses of sediment.

Which of the following is one of the smaller continents formed by the breakup of Pannotia?

Baltica

Identify the statement that is true about radiometric dating. A. It can be used only if some uranium is present in the rock. B. Dating of an individual sand grain in a sandstone accurately dates the sedimentary rock's formation. C. Dating of metamorphic rock tells when the high temperatures of metamorphism cooled below the closure temperatures of the minerals involved. D. It can begin only when the isotopes heat up enough to decay.

C. Dating of metamorphic rock tells when the high temperatures of metamorphism cooled below the closure temperatures of the minerals involved.

Which of the following statements is true? A. The human genus, Homo, first appeared more than 7 million years ago. B. The Mesozoic is known as the Age of Mammals. C. Fossils of modern humans (Homo sapiens) date back about 200,000 years. D. Hominins first appeared in the late Mesozoic.

C. Fossils of modern humans (Homo sapiens) date back about 200,000 years.

Identify the true statement. A. The second (as a unit of time) is defined in terms of energy changes within the chromium atom. B. Time zones are 15° of latitude wide. C. Time zones are set in relation to the time at the astronomical observatory in Greenwich, England. D. Denver (latitude 40°N, longitude 105°W) is 10 time zones away from Greenwich, England (latitude 51°N, longitude 0°).

C. Time zones are set in relation to the time at the astronomical observatory in Greenwich, England.

Which of the following lists fits the order of these three descriptions: Age of Mammals, Age of Dinosaurs, and longest geologic time period.

Cenozoic, Mesozoic, Precambrian

Identify the true statement. A. The "radiometric clock" starts when a radioactive mineral warms above its closure temperature. B. Carbon-14 dating is used to date anything that was once alive, regardless of age. C. Scientists can date any radioactive material back only three half-lives; after this, there's not enough parent material left to measure. D. Isotopic dating can be used only in a closed system, where neither parent material nor daughter material has escaped.

D. Isotopic dating can be used only in a closed system, where neither parent material nor daughter material has escaped.

Which of the following statements is true? A piece of gneiss radiometrically dated as 4.4 billion years old is the oldest whole rock yet found. B. Shale that contains land plants probably formed in an alluvial fan or a stream channel. C. Marine limestone that overlies alluvial fan conglomerate shows that the sea level dropped at that site. D. Limestone that contains coral fossils probably developed in a shallow sea.

D. Limestone that contains coral fossils probably developed in a shallow sea.

Identify the true statement. A. The Moon is now closer to the Earth than it originally was. B. Geologists generally agree that plate-tectonic activity began in the Hadean Eon. C. Eighty percent of the Earth's continental crust existed by the end of the Hadean Eon. D. There was intense meteorite bombardment of the Earth about 4 Ga that destroyed the Earth's earliest crustal rock.

D. There was intense meteorite bombardment of the Earth about 4 Ga that destroyed the Earth's earliest crustal rock.

Which of the following statements is true? A. An unconformity is a break in the rock record indicating that the area was underwater for millions of years. B. A paleosol is a rock layer identified by such factors as rock type and approximate geologic age. C. The generally accepted age of the Earth is 4.56 million years. D. Varieties of an element that differ only in the number of neutrons are called isotopes.

D. Varieties of an element that differ only in the number of neutrons are called isotopes.

Which of the following refers to fossils of early multicellular invertebrates that are 565 to 620 million years old?

Ediacaran fauna

Identify the true statement.

Henri Becquerel discovered principles of radioactivity, which led to the determination of the Earth's age.

The first feathered birds appeared in the

Jurassic

According to this diagram, which shows the stratigraphic record produced when sea level rises and falls over time, which of the following statements is true?

Sand, covered by limestone and then shale, represents a sea-level rise.

A corpse with flesh intact, found in the Alps in 1991, was dated by the carbon-14 method and showed a parent-daughter isotope ratio of approximately 1:1, with slightly more parent material than daughter material. The half-life of carbon-14 is 5,730 years. On the basis of this information, decide which of the following statements is true.

The age could logically be 5,300 years.

Which of the following is/are useful in identifying mountain belts that have eroded away and therefore do not have obvious topographic features?

unconformities

An area of slightly dipping sedimentary rock layers has large inclusions and is intruded by an igneous dike. By applying the basic principles for determining relative ages, decide which of the following is the true statement.

The igneous intrusion (the dike) "baked" (metamorphosed) the sedimentary rock that it touched.

A hominin (human family) skull was found in a shale layer between two fine-grained igneous rock layers. There were no baked zones on the rocks above the igneous layers. The skull had been 100% fossilized and changed to stone; there was no original skull material left. On the basis of this information, decide which of the following statements is true.

The skull itself cannot be dated, because it is no longer organic material and it is not igneous material. The age of the skull is determined by its position between the igneous layers.

What type of unconformity forms when sedimentary rocks overlie either igneous or metamorphic rocks?

a nonconformity

Tiktaalik, is significant because it represents

a transition from lobe-finned fish to amphibians that could walk on land.

Which of the following was a component of the Earth's Hadean atmosphere?

ammonia

Uniformitarianism

can be illustrated by scientists' seeing pillow lava forming only underwater, then theorizing that pillow lava found high in the mountains today did nevertheless form underwater.

Theoretically, "snowball Earth" conditions of the late Proterozoic Eon would have persisted forever, were it not for greenhouse warming caused by

carbon dioxide.

Which of the following is a common, cheap, and useful form of limestone that consists of microscopic marine algae shells and shrimp feces, and that is commonly found in thick Cretaceous-age deposits in Europe.

chalk

Before the development of isotopic dating methods, scientists estimated the age of the Earth by

comparing rates of change on the Earth's surface today with the geologic record.

The boundary surface between two stratigraphic formations is called a

contact.

Which of the following is a method used to determine numerical age?

counting ice bands in a glacier

Which of the following accurately ranks the subdivisions of geologic time in order from largest to smallest?

eon, era, period, epoch

The Great Oxygenation Event, which added abundant oxygen to the atmosphere beginning about 2.4 Ga, was due to the

evolution of photosynthetic organisms in oceans.

Which of the following methods for determining the age of materials is a radiometric dating technique?

fission-track analysis

Geologists believe that the impact of a 13-km-wide meteorite 65 million years ago

generated a hot-air blast and blaze that caused worldwide forest fires.

In 1815, William Smith correlated strata from many locations and plotted the information on paper to show the spatial distribution of rock units on the Earth's surface. This document was the first modern

geologic map.

Which of the following are fossil plants?

gymnosperms and angiosperms

Internal differentiation

happened just before, or possibly simultaneously with, the Earth's collision with a protoplanet that blasted away Moon material.

Banded iron formations (BIFs) formed

in the Proterozoic deep ocean.

There is very little rock record for the Earth's first 600 million years because

intense meteorite bombardment may have destroyed most land surface.

The Paleozoic Era ended with a mass extinction event that was likely caused by

intense volcanic activity.

Gymnosperms (naked-seed plants like conifers) were widespread in the late Paleozoic, but angiosperms (flowering plants) gained dominance in the

late Mesozoic

The first life forms

may have been simple cells of bacteria and cyanobacteria (blue-green algae).

Identify the appropriate time period when vascular plants with woody tissues, seeds, and veins shared the land with spiders, scorpions, insects, and crustaceans, while jawed fish cruised the oceans and the first amphibians left water to visit land.

middle Paleozoic

We know that the atmosphere became more oxygen-rich around 1.8 billion years ago (Ga) because of geologic evidence such as

redbeds that formed after 1.8 Ga

Which of the following was important in determining the cause of the K-Pg (Cretaceous-Paleogene) extinction?

shocked quartz

Rodinia, Pannotia, and Pangaea are all names of

supercontinents.

During the Pleistocene Ice Age,

the continental shelf west of Alaska was exposed and allowed migration of animals and people from Asia to North America.

If you equate all of the Earth's history to one calendar year, the history of our species (Homo sapiens) would occupy

the last hour before midnight on New Year's Eve.

Nicolas Steno's observations of fossil shark teeth convinced him that

the rock they were in originated as loose sand, not solid rock.