Geophysics

Question 1

He discovered Uranus.

Answer 1

William Herschel

Question 2

He proposed the geocentric model.

Answer 2

Aristotle

Question 3

He proposed the heliocentric model.

Answer 3

Aristarchus

Question 4

Volume of Earth

Answer 4

1.0832 × 10^21 m3

Question 5

Mass of Earth

Answer 5

5.9736×10^24 kg

Question 6

Mean Density of Earth

Answer 6

5.515×10^3 kg

Question 7

Area of Earth

Answer 7

5.10×10^14 m2

Question 8

An empirical formula to express the approximate distances of the planets from the Sun

Answer 8

Bode’s Law

Question 9

Rate of increase of Earth-Moon distance.

Answer 9

3.7 cm/yr

Question 10

Distance between Earth and Moon

Answer 10

384,400 km

Question 11

Enumerate the Milankovitch cycles and the periods

Answer 11

Eccentricity: 100,000 years
Precession: 26,000 years
Obliquity: 41,000 years

Question 12

The flattening ratio of the Earth

Answer 12

1/298

Question 13

A method in geophysics used to image sections of the Earth’s subsurface using different geophysical surveys

Answer 13

Tomography

Question 14

Directly measures small differences in the strength of gravity. What is its accuracy?

Answer 14

Gravimeter. Accuracy: 0.1 mgal

Question 15

Gravity correction done by repeatedly recording readings from a fixed “Base Station” throughout the day.

Answer 15

Drift Correction

Question 16

Gravity correction that accounts for the gravitational attraction of the mass above sea level datum. Assumes the topography is flat.

Answer 16

Bouguer Correction

Question 17

Periodic gravity variation correction caused by the combined effects of Sun and Moon.

Answer 17

Tidal Correction

Question 18

Utilizes one current electrode and one potential electrode at a specific distance a.

C1-a-P1

Answer 18

Pole-pole

Question 19

Utilizes two current electrodes separated by a distance, a, from two potential electrodes separated by distance, a. The distance between two Cs and Ps are given by na.

C2-a-C1-na-P2-a-P1

Answer 19

Dipole-dipole

Question 20

Utilizes two paired current and potential electrodes separated by distance a, with each pair also separated by distance a. Potential electrodes are closer to each other while current electrodes are farther from each other.

C1-a-P1-a-P2-a-C2

Answer 20

Wenner

Question 21

Utilizes two paired current and potential electrodes separated by distance na, with each pair separated by distance a. Potential electrodes are closer to each other while current electrodes are farther from each other.

C1-na-P1-a-P2-na-C2; a<na

Answer 21

Schlumberger

Question 22

Describe the Eotvos effect when an object is moving against and along Earth’s rotation.

Answer 22

1.) Moving against Earth’s rotation = lesser upward centrifugal force = object weigh less
2.) Vice versa

Question 23

_________ and __________ fused together to form the supercontinent Laurussia

Answer 23

Baltica and Laurentia

Question 24

He visualized the heavens as a celestial sphere that surrounded the flat Earth.
a. Anaximander
b. Claudius Ptolemy
c. Nicolas Copernicus
d. Eratosthenes

Answer 24

Anaximander

Question 25

He estimated the Earth's circumference a. Anaximander b. Claudius Ptolemy c. Nicolas Copernicus d. Eratosthenes

Answer 25

Eratosthenes

Question 26

He proposed the geocentric model a. Anaximander b. Claudius Ptolemy c. Nicolas Copernicus d. Eratosthenes

Answer 26

Claudius Ptolemy

Question 27

Is the largest dwarf planet in the Solar System, what is the 2nd largest dwarf planet?

Answer 27

Pluto (1st) Eris (2nd)

Question 28

is the largest object in the asteroid belt between Mars and Jupiter, and it's the only dwarf planet located in the inner solar system.

Answer 28

Ceres

Question 29

is the largest of the five known natural satellites of Pluto

Answer 29

Charon

Question 30

Calculated the accurate values of the parameters of Earth's orbit. a. Carl Friedrich Gauss b. Lord Charles Cavendish c. Keith Edward Bullen d. Tycho Brahe

Answer 30

Tycho Brahe

Question 31

Created a model of the internal structure consisting of 7 concentric shells. a. Carl Friedrich Gauss b. Lord Charles Cavendish c. Keith Edward Bullen d. Tycho Brahe

Answer 31

Keith Edward Bullen

Question 32

Coined the value of Gravitational Constant G to be 6.754×10^-11. a. Carl Friedrich Gauss b. Lord Charles Cavendish c. Keith Edward Bullen d. Tycho Brahe

Answer 32

Lord Charles Cavendish

Question 33

Developed a method of absolute determination of the intensity of the Earth's magnetic field. a. Carl Friedrich Gauss b. Lord Charles Cavendish c. Keith Edward Bullen d. Tycho Brahe

Answer 33

Carl Friedrich Gauss

Question 34

a low-eccentricity Kuiper belt object (KBO) that orbits beyond Neptune and is not controlled by an orbital resonance with Neptune.

Answer 34

Classical Kuiper Belt Object or Cubewanos

Question 35

Largest Satellite in the solar system.

Answer 35

Ganymede

Question 36

The ratio of the intensity of the remanent magnetization to that of the induced magnetization.

Answer 36

Konigsberger Ratio

Question 37

The two natural satellites of Mars a. Io b. Phobos c. Ganymede d. Charon e. Deimos

Answer 37

Deimos and Phobos

Question 38

Planets that rotate clockwise direction

Answer 38

Venus and Uranus

Question 39

Crest vs. Hinge

Answer 39

Crest - highest point Hinge - Maximum stress point

Question 40

Crest vs. Hinge

Answer 40

Crest - highest point Hinge - Maximum stress point

Question 41

Describe Harmonic and Disharmonic Folding.

Answer 41

The thinner the rock the more harmonic. Same types also result to more harmonic. More Harmonic, the shorter the wavelength

Question 42

Why do faults have a tendency to branch out on the near surface?

Answer 42

Because there is lesser confining pressure near the surface

Question 43

What is the width of the Philippine Fault Zone?

Answer 43

5 km

Question 44

In a rock core, if you see a repetition of bed, it is an indication of what fault? If there is an omission of strata what fault is it?

Answer 44

Repetition - Thrust Fault Omission - Normal (but can also be Unconformity)

Question 45

The presence of listric fault connotes a presence of _________ bed

Answer 45

thick incompetent bed

Question 46

Series of listric and/or thrust faults

Answer 46

Imbrication system

Question 47

Also called an imbricate structure

Answer 47

Schuppen structure

Question 48

Allochthons are not common in the Philippines because?

Answer 48

Because our rocks are denser compared to continental rocks which are harder to thrust

Question 49

Subduction should reach ______ km to create volcanoes.

Answer 49

90-100 km

Question 50

a weather device that is designed to be dropped out of an aircraft at specified altitudes and due to the force of gravity, drop to the Earth

Answer 50

Dropsonde

Question 51

A law that states that good absorbers of a given wavelength are also good emitters of that wavelength.

Answer 51

Kirchoff's rule

Question 52

It is composed of 8% Alkali and 45% SiO2 a. Trachyandesite b. Trachybasalt c. Basaltic Trachyandesite d. Tephrite

Answer 52

Tephrite

Question 53

A log that measures the resistivity using two electrodes and having a limited area of investigation of from 5 to 10 times the electrode diameter

Answer 53

Single-Point Resistivity Log

Question 54

What signal is the most important for seismic refraction profiles?

Answer 54

**First arrival time of the seismic waves**. This signal is critical because it provides the earliest indication of seismic energy traveling through subsurface layers, allowing for the determination of layer velocities and depths. Other signals are not that important because: ***Subsequent arrivals***: These may include reflected or refracted waves from deeper layers, but they do not provide as direct information about the near-surface conditions. ***Amplitude variations***: While they can indicate material properties, they are secondary to the timing of first arrivals in establishing depth and velocity profiles.