2nd quarter examination in earth and life science

4.6 billion years ago

How many years ago did the earth began to start life?

Rocks, minerals, radioactive isotopes, rock layers, fossils, sediments, geological structures

Give at least 5 evidences used by scientists to study the geologic time and sequence of the earth (Consider this as CORRECT if you manage to give 5 examples present on the key answers)

Stratified rocks

These are rocks formed in recognizable layers

Strata

This is what you call the stratified rocks

Weathered, transported, eroded, compacted, cemented, deposited

Give at least 4 examples on how sediments form stratified rocks (Consider this as CORRECT if you manage to give 4 examples present on the key answers)

Sandstone, shale, limestone

Give the 3 examples of stratified rocks

Law of superposition

This is a principle of relative dating where the scientist is measuring how old or young the rock undisturbed rock formations of sedimentary rocks—oldest layers are at the bottom while younger layers are at the top

Relative dating

This is a kind of dating where the scientist is only identifying the order of when the rock layers are formed. It does not necessarily give an exact numerical age

Superposition, original horizontality, cross-cutting relationship, inclusions, and faunal succession

Give the 5 principles of relative dating (uncomformity not included)

Original horizontality

It states that rocks are always beginning in a horizontal position

Cross-cutting relationship

This states that anything that cuts across rock layers are younger

Unconformity

States that there is a gap that forms in between the rock layers due to erosions

Inclusions

This states that fragments inside the rock are generally older than the rock itself

Faunal succession

This refers that fossils from organisms occur in reognizable sequence and can be seen in rock layers to identify the geologic time frame of its existence

Absolute dating

This is a kind of dating that gives an exact estimation and approximation or in numerical age

Radiometric dating

This is a principle of absolute dating where it uses radioactive decay of isotopes to identify the parent isotopes to the daughter product

Half-life

This is the time required for half of a radioactive sample to decay

Carbon-14, potassium-argon, uranium lead

Give 3 examples given for Half-life (refer to the ppt)

Geologic time scale

This is the system used to organize earth’s history and help scientists to identify when major events occur

Eon, era, period, epoch

Give the subdivisions of the geologic time scale

Hadean, archean, proterozoic, phanerozoic

Give the 4 major eons

Hadean eon

The eon where the formation of the early earth happened

Archean eon

The eon where the early crust became stable and created the first and earliest life

Proterozoic eon

The eon where major changes in the earth’s atmosphere started to happen, and created a more diverse early life than before

Phanerozoic eon

Also known as the current eon where abundant fossils are seen, and created a major diversification of life

Paleozoic, mesozoic, and cenozoic era

Give the three era in the phanerozoic eon

Ancient life

What is the other name called for the paleozoic era?

Trilobites

What is the most abundant fossil marker in the paleozoic era?

Paleozoic era

This is the era of marine life, new life forms, expansion of life, creatins of forests, early reptiles, and ended with the mass extintion in the permian period

Mesozoic era

This is the era where dinosaurs ruled the earth, marine reptiles are abundant, first birds are seen, early mammals and flowering plants became more diverse, and ended with another major mass extinction

Age of reptiles

Another name for the mesozoic era

Ammonites

The abundant marker fossils present in the mesozoic era

Cenozoic era

This is the current era

Ancient environments, past climates, changes in life, mass extinction, movement of continents, foration of mountains, changes in oceans, geological events

Give at least 3 geological evidence that can provide information in: (consider it correct when the thought is similar)

Cenozoic era

This is the era where mammals, birds and plants became diverse, as modern ecosystems started to grow. Primate and human life are also starting to begin

Marker fossils

This helps scientists to identify intervals of geologic time to correlate rock layers

Guide fossils

Marker fossils are also called as?

Wide geologic distribution, short geologic time range, abundance, distinctive features

Give the 4 characteristics of a fossil before being considered as a marker fossil

Trilobites and ammonites

Give 2 examples of marker fossils

Trilobites

These are marker fossils present in the paleozoic era, It is a distinct marine organism used to identify paleozoic rocks

Ammonites

This is a marker fossil that is a marine organism. It is used to correlate mesozoic rocks. They have a distinctive coiled shells

Correlation

This is the proccess of comparing marker fossils to identify the geologic time time scale

Carbon-14

This isotope is useful for relatively recent organic materials

Potassium-argon

This isotope is useful for dating many older volcanic and geological materials

Uranium-lead

This isotope is useful for datingvery old rocks and minerals

Geologic processes

These are the natural processes that continuously change the physical structure and appearance of earth

Create landforms, destroy landforms, move sediments, form rocks, break down rocks, build mountains, create volcanoes, cause earthquakes, change the shape of earth’s surface

Give at least 5 results a geologic process can form (consider it correct if the thought is similar

Exogenic processes and endogenic processes

Geologic processes can be generally classified into 2 major divisions

Exogenic processes

This is the process that occur at or near the earth’s surface and are primarily driven by external forces

Weathering, erosion, transportation, deposition, mass wasting

Give the 5 examples of exogenic processes

Endogenic processes

These are the processes that originates from within earth and are driven by earth’s internal energy

Earthquakes, volcanism, faulting, folding, mountain building

Give 5 examples of endogenic processes

Solar energy, water, wind, ice, gravity, changes in temperature, organisms

Give at least 4 factors driving the exogenic processes

Weathering, erosion, transportation, deposition

Give the sequence of exogenic process

Mass wasting

This is another important exogenic process caused mainly by gravity

Weathering

This is the breakdown or alteration of rocks and minerals at or near the earth’s surface

Weathering

What exogenic process does not involve the transportation of materials?

Weathering

The exogenic process which the rock remains in place while it is being broken down or chemically altered

Physical/mechanical weathering, chemical weathering, biological weathering

Give the 3 major types of weathering

Physical/mechanical weathering

This is the breakdown of rocks into smaller pieces without changing their chemical composition, the rock becomes smaller but its mineral remain chemicaly the same

Temperature change, frost wedging, abrasion, exfoliation

4 examples of physical or mechanical weathering

Temperature change

The type of mechanical weathering where rocks expand when heated and contract when cooled, the repeated expansion and contraction can produce cracks

Frost wedging

This is an example of mechanical weathering where water enters cracks in rocks, when the water freezes, it expands and pushes against the walls of the crack

Abraision

An example of mechanical weathering where rocks and sediments collide with or scrape against one another that can occur through moving water, wind, and glaciers

Exfoliation

An example of mechanical weathering where the outer layers of rock may peel away due to pressure release and expansion

Chemical weathering

This weathering occur when minerals in rocks are chemically altered through reactions with substances in the environment

Water, oxygen, carbon dioxide, acid

4 common agents in chemical weathering

Oxidation, carbonation, dissolution, dissolution, hydrolysis

5 major types of chemical weathering

Oxidation

When oxygen reacts with minerals, especially iron-bearing minerals

Carbonation

When carbon dioxide dissolves in water and forms a weak carbonic acid and can react with certain minerals, especially those found in limestone

Dissolution

A chemical weathering example where Some minerals dissolve when they come contact with water

Hydrolysis

A chemical weathering where water reacts with minerals

Biological weathering

This kind of weathering occurs when living organisms contribute to the breakdown of rocks

Tree roots growing into cracks, burrowing animals, microorganisms, human activities

Give at least 3 examples of biological weathering

Erosion

This is the removal and transportation of weathered materials from one place to another

Weathering

Also known as breakdown

Erosion

Also known as removal and transportation

Water, wind, glaciers, gravity

Give the 4 agents of erosion

Transportation

After rocks are weathered and removed through erosion, the materials can be transported to another location

Deposition or sedimentation

This occurs when transported sediments settle or accumulate in a new location

Ocean basins

Where does many sediments eventually settle?

Compacted, cemented, sedimentary rocks

The process to create sedimentary rocks when it reaches the ocean basin

Mass wasting

This is where the downslope movement of soil, rocks, and other earth materialsfall off due to gravity. Does not agents to transport rocks

Plate tectonics

The earth’s outer rigid layer is divided into large pieces called?

Earthquakes

This is the sudden release of energy within earth that produces seismic waves

Volcanism

Refers to the movement of magma and volcanic materials from earth’s interior toward or onto the surface

Faulting

This happens when rocks break and move because of tectonic forces

Fault

This is a fracture or zone of fractures in earth’s crust along which movements is occured

Normal fault, reverse fault, strike-slip fault

Basic types of faulting

Faulting

This occurs when layers of rocks bend because of compressional forces. Rocks may bend rather than bend

Anticline, syncline

2 common types of folding

Mountain building

This commonly occurs through tectonic processes

Orogeny

Another term for mountain building

Natural hazard

This is a natural process or event that has the potential to cause injury, loss of life, property damage, or environmental destruction

Geologic hazards

These are potentially dangerous events or processes associated with the earth’s structure, materials and movements

Ground shaking, ground ruptures, liquefication, earthquake-induces landslides, tsunamis

5 hazards associated with earthquakes

Ground shaking

Vibrations of the ground that may damage buildings, bridges, ad other structures

Ground rupture

The breaking and displacement of the ground along an active fault

Liquefication

A process in which loose, water-saturated soil loses strength during strong shaking and may behave like a liquid

Earthquake-induced landslide

The movement of soil, rocks, or debris down slopes riggered by ground shaking