geo hw 12

The modern oceans are a major repository for the greenhouse gas ________, which some organisms utilize to make their shells.

CO2

Which planet in the solar system had more mass accreted to it via a comet that impacted in 1994?

Jupiter

.-The _________ marks the timing of the extinction event tied to the demise of the dinosaurs and is visible in the rock record as a thin layer of sediment that can be found worldwide.

KT boundary

3. ______________ created an atmosphere that ultimately enabled the development of higher life forms.

Volcanic outgassing

At the start of the Mesozoic, the climate was ________.

dry

Earth's primitive atmosphere evolved from gases ________.

expelled from within the earth

The major source of free oxygen in the atmosphere is from ________.

green plants

The first elements to form after "Big Bang" were ________.

helium and hydrogen

As the solar system began forming, the first materials to condense into small particles were ________ and nickel carbon silicon nitrogen oxygen none of these

none of these

Mammals are derived from __________, which are derived from __________.

reptiles; amphibians

4. Without ___________________, elements with a higher atomic number than iron would not exist.

Supernova

_________ may have caused global warming, which would have warmed the oceans, decreasing the amount of dissolved oxygen and increasing the number anaerobic bacteria present in the ocean. These bacteria would have generated massive amounts of toxic hydrogen sulfide, leading to the Great Permian Extinction.

-volcanism

When did the supercontinent Pangaea form?

250 million years ago

The earth formed approximately ________ years ago.

4,600,000,000

5. ___________ is the process by which the planets formed from material in the solar nebula and the process by which the Moon formed from impact debris.

Accretion

Which of the geologic provinces in Figure 1 might have been added in the time leading up to the formation of Pangaea?

Appalachian Province

Put the following events in the order they occurred to lead to the formation of the solar system: A. Earth was bombarded by new materials after formation. B. Earth separated into layers based on the weight of materials. C. Hydrogen and helium formed atoms. D. Outgassing of volcanoes produced a primitive ocean.

C, A, B, D

When landmasses were forced together to create the first continents, why didn't the continents subduct?

Continental crust is thicker and has a lower density.

1. _______________ is responsible for the development of Earth's crust, mantle, and core. The core is responsible for creating Earth's magnetic field.

Density differentiation

What processes created the Earth's moon?

Earth was struck by a large planetesimal. Debris from Earth and another planetesimal accreted.

-The _______________was a massive extinction event in which 90 percent of marine life and 70 percent of vertebrate land species were wiped out, creating niches that dinosaurs would eventually fill.

Great Permian Extinction

Earth's core, mantle, and crust formed during the ________.

Hadean

The supercontinent of Pangaea began to break up during the ________ era.

Mesozoic

2. Debris that orbited Earth after a giant impact accreted and contributed to the formation of the____________.

Moon

Though life existed before the Cambrian explosion, it was likely not present with the same diversity. Life in the oceans was incredibly active before the first species began to move onto the continents. After the Cambrian explosion, the number of species in oceans greatly increased. Greater competition among species led to more rapid and advanced adaptations to escape predators. Adaptations also led to the origin of amphibians and plants, leading the habitation of land. Amphibians were able to move into swampy regions and tidal pools, escaping predators and exploring new habitats. Similarly, plants faced new challenges moving onto land, including coping with wind and gravity without the support provided by ocean water, but ultimately thriving and evolving into large trees. A drier period, the Paleozoic Era, resulted in vast changes of land plants and animals. Green algae require freestanding water to survive and are ancestors of modern plants. Early in this era, the first plants appeared on land that did not require freestanding water. A group of plants, called the gymnosperms, proliferated later in the era because their seeds were well adapted for the drier environment of the time. The drier climate was problematic for amphibians because they must return to water to lay their eggs. This was an opportunity to gain a competitive advantage for a new group: the reptiles. The eggs of reptiles have a shell, allowing them to be laid on land, which was a primary factor in the spread of these animals. Then, the Great Permian Extinction occurred. This extinction was likely the result of global warming associated with volcanism. Estimates of extinction are 90 percent of marine species and 70 percent of terrestrial species. The warming would have allowed anaerobic bacteria to thrive, putting large amounts of hydrogen sulfide into the atmosphere. This extinction paved the way for the dinosaurs, who thrived during the Triassic, Jurassic, and Cretaceous periods, until the KT boundary (Cretaceous-Tertiary boundary). The timing of the KT boundary coincides with the carbonaceous meteorite impact that lead to the extinction the dinosaurs. Conditions on Earth influenced evolution and how biodiversity changed through time. Place the following events in order from earliest to most recent.

Mesozoic era- dinosaurs and many other species become extinct. paleozoic era- the great permian extinction occurs causing loss of many marine and terrestial vertebrates species. first vascular plants invade the land- green algae were ancestors of this organisms it had restricted mobility and size. first amphibians- appearance of this group allowed travel from swamp to land. first reptiles- this group's shell covered eggs offsprings to be born outside the water. gymnosperms flourish- plants adapetd to drier climates seeds were fertilized without freestanding water fishes flourish- increased predator meant adaptions bigger brains deveopment of acute senses and faster mobility.

What would have happened to the earth if it were 10% closer to the sun?

Our atmosphere would consist mainly of carbon dioxide.

What is the relationship between planetesimals and protoplanets? Choose all that apply.

Planetesimals combine to form protoplanets .Planetesimals are smaller than protoplanets.

Most ________ rocks are devoid of fossils, which hinders correlation of rocks.

Precambrian

Using Figure 2, determine when the majority of the African craton had been formed.

Proterozoic Eon

Refer to the accompanying pictures, which include some of the important events leading to the formation of Earth. Rank the images in the correct order of events from first to last.

Rank from first to last. B D C A F E

About 2.2 billion years ago, a significant amount of oxygen appeared in the atmosphere. How does this relate to life on Earth during this time and after?

Significant amounts of oxygen in the atmosphere contributed to the formation of ozone. This protected life from ultraviolet radiation. Photosynthesis became an effective way to convert energy from the sun, and oxygen was a significant by-product.

___________ may have caused a global cooling event as suspended dust blocked the Sun. Without the Sun's energy, many plants would have died. Without plants to feed on, many creatures would also have died

a carbonaceous meteorite

Early Earth was hot because ________.

a combination of collisions and radioactive decay produced heat

The following images depict some of the events leading to the formation of Earth. Drag and drop the correct descriptions for each of the events.

left to right top continual bombardment and the decay of radioactive elements produce..... outgassing produces earth's primitive atmosphere.... accretion of planetesimals forms earth and the ..... left to right bottom solar nebula begins to ..... as material collects to form the protosun...... chemical differentiation produces earth's layered ......

Which animal are all tetrapods derived from?

lobefin fish

-__________ thrived in the millenia following the extinction at the KT boundary.

mammals

How was material generated to create continental masses?

partial melting of subducting plates

Which processes created the magma ocean that used to exist on the planet Earth?

radioactive decay bombardment

-The extinction of ____________was likely the result of rapid climate changes associated with the impact of a large carbonaceous meteorite.

the dinosaurs

The North American Cordillera formed as a result of ________.

the subduction of the Pacific basin beneath North America

Hydrogen and Helium would have been the first elements to form after the Big Bang. How were heavier elements produced?

the supernova of early stars

One important reason we do not know much about the geologic history of the Precambrian is that ________.

there are very few fossils preserved in Precambrian rocks

What geologic features created the earliest fragments of continental crust?

volcanic island arcs

When did dinosaurs go extinct?

65 million years ago, at the Cretaceous-Paleogene boundary

Conditions on Earth influenced evolution and how biodiversity changed through time. Place the following events in order from earliest to most recent.

EARLIEST cambrian explosion dominance of amphibians earth hit by a large carbonaceous meteorite diversification and dominance of mammals extinction of giant mammals like mastodons MOST RECENT

What common bone structure is shared in the forelimbs of the lobefin fish and amphibians?

humerus, radius, ulna, and finger bones

The Archaeopteryx is an early bird that came into existence at the time of the dinosaurs. It had a mix of reptilian and bird features. Of the physical features listed below, which are reptilian features?

Long tail Teeth Wing claws

__________ were able to diversify after the extinction of the dinosaurs.

Mammals

Which region of North America has the oldest parts of the continent?

Northern Canada

The space and time over which geologic processes occur are massive. The stromatolites and shales were deposited during the Cambrian period ~540 to 485 million years ago. The current Canadian Rockies and adjacent interior seaway formed between ~145 and 60 million years ago. Glaciations became rather common and cyclical over the last few million years of Earth's history, known as the Quaternary. It is the job of geologists to recognize periods where processes, landforms, or the boundary conditions (climate and tectonics) were similar. By doing this systematically in many locations, geologists have devised a timescale of important episodes in Earth's history. This permits other geologists to more readily place their observations into the context of larger geologic episodes that span across continents and the entire globe. Given the information in this activity, place the features you identified in Part A in the order that they occurred chronologically. Rank from oldest to youngest elevation.

OLDEST stromatolites formed shale of the arctomys formation...... cretaceous interior seaway glacier scoured hillslope YOUNGEST

The features identified above provide evidence of past environments in the Cirque Peak area. These features require certain geologic and environmental conditions to form. In this part, consider these features and conditions, which are described below. Climate change alters sea level, and tectonics change topography. These processes can lead to shifts in shoreline position or even make them disappear. Rising or falling sea level can be initiated by global climate change or tectonic events like mountain building. During cold periods, like ice ages, more of the world's water is stored in continental glaciers (e.g., Greenland), causing sea level fall. As the planet warms and the ice melts, sea level then rises. Tectonic processes create mountains and adjacent inland depressions (basins) that in turn collect water and sediments transported from the highlands. During the formation of the Canadian Rockies, a seaway formed between the Rockies and the continental interior of the United States and Canada. This waterway, called the Cretaceous Interior Seaway, existed ~145 to 66 million years ago and spanned from the present day Gulf of Mexico north through western Canada. Some of the sediment deposited at the base of this sea eroded from the Canadian Rockies. Mountain topography is created by tectonic processes that deform and uplift rock. However, its form is highly dependent on the various processes that erode it. For example, hillslopes can erode by landslides, rivers, soil creep, or even glaciers; each process leaves its unique signature.

Rainwater and rivers once flowed from the Canadian Rockies into the Cretaceous Interior Seaway. There is evidence that the location shown in the Gigapan image was once near a shoreline. The mean annual temperature of the location shown in the Gigapan image was once much lower than it is today.

Today, banded iron formations, a type of sedimentary rock found in many locations, provides evidence for the dramatic increase in oxygen released by cyanobacteria. Oxygen reacted with iron dissolved in the ocean. This created black iron oxide minerals (like hematite and magnetite). These minerals, together with reddish-colored chert (a very fine-grained quartz that contains small amounts of iron), precipitated out of solution, collected at the sea floor, and eventually turned into banded iron formations. The majority of banded iron formations were formed about 2.2 billion years ago during the Precambrian Eon. During this time, widespread iron oxidation, in large part due to oxygen production by cyanobacteria, provided the minerals that make up banded iron formations. Take a look at the image showing banded iron-rich rocks deposited during the Precambrian eon. The statements below describe conceptual relationships between iron-rich deposits and Earth's early atmosphere. Determine if these statements are true or false.

TRUE these rocks are evidence that oxygen and iron became iron....... these rocks provide evidense that photosythetic batcteria.... these rocks are evidence that significant amount of iron were ........... these rocks are evidence that oxygen must have been present during the precambrian....... False these rocks are evidence that earth's atmosphere.... these rocks are evidence that oxygen was not yet present during..... these rocks are evidence that there was very little and isolated.....

How would sediments caught between two accreting landmasses appear? (What feature or features would you expect to see?)

folds and foliated rocks

Which geologic event was responsible for adding the Grenville Province to North America approximately 1.2 billion years ago?

formation of Rodinia

At the start of the Paleozoic, North America ________.

had no plants or animals

What feature, marked with an A in Figure 1, is responsible for creating the oceanic plateau?

mantle plume

Explore the Gigapan image and identify these features in the snapshot below.

top to bottom red beds folded shale glacially carved hill slope stromatolites