GEOPHYSICS (BOREHOLE)

Question 1

Drilled to study subsurface lithology along the path of a hole which can help interpret a 3D picture of the study area

Answer 1

Borehole logging

Question 2

Process

Answer 2

1) Shallow NONCORE holes are excavated by reverse-circulation drilling
2) Deeper Holes are drilled by rotary drills with cutting units an tungsten-carbide or diamond bits

Question 3

If a core barrel is recovered it is used for?

Answer 3

Lithology, Mineralization, and Structure Analysis

Question 4

the process of using electric instruments to continuously measure the properties of a formation, in order to make decisions about drilling and production operations.

Answer 4

Wireline Logging

Question 5

The cylindrical metal tube which houses the probe in borehole surveys

Answer 5

Sonde

Question 6

How is data logging conducted in borehole?

Answer 6

Paper Strip and
Magnetic Tape in Analog

Question 7

Properties obtained

Answer 7

1) Formation Thickness
2) Lithology
3) Porosity
4) Permeability
5) Proportion of Water and hydrocarbon saturation
6) Temperature

Question 8

A postdiscovery method done by enhancing resisitivity contrast between the host rock and the sulfide ore which is indicative of mineralization continuity in strike, dip, shape and interconnectivity between numbers of intersections within a borehole

Answer 8

Mise a la Masse
“excitation of the mass”

Question 9

Setup

Answer 9

positvie current electrode is planted into the condctive mass thrugh a pit or drill hole

Question 10

what is the measured propoerty?

Answer 10

Surface potentials are measured with respct to the distant electrode and the distribution of which reflects the geometry of the conductive mass

Question 11

Logs used to identify borehole size and shape

Answer 11

Caliper Logs

Question 12

Logs used to differentiate sediments or sands

Answer 12

Lithology Logs

Question 13

A scintillation detector that measures the Natural Radiation from a formation

Answer 13

Gamma Ray

Question 14

A measurement vs depth of the potential difference between the volatage in the wellbore as a function of depth and that of an electrode on the surface

Answer 14

Spontaneous Potential

Question 15

If the deflections in a log is towards the right the sediment is said to be?

Answer 15

Shale

Question 16

If the deflections are to the left the sedment is said to be?

Answer 16

Sand

Question 17

Logs that determine porosity and fluid types

Answer 17

Porosity logs

Question 18

This measures tha bulk density of the formation (Rock and Fluid)

Answer 18

Density Porosity

Question 19

Measures the hydrogen content in a porosity log

Answer 19

Neutron porosity

Question 20

If there is a red line on the left of the black line, the porosity is

Answer 20

Highly Porous (Shale)

Question 21

If there is a red line on the right of the solid black line, the porosity is

Answer 21

Low

Question 22

When the red overlaps the black the lithology is

Answer 22

Wet Sand or Oil Sand

Question 23

Logs that relate to seismic velocity

Answer 23

Velocity or Sonic Logs

Question 24

Logs used to identify HC accumulation

Answer 24

Resistivity Logs

Question 25

IN deep resistivity logs 4ft, high values mean

Answer 25

HC and Low Porosity

Question 26

Low values means

Answer 26

Wet sand

Question 27

If there is a separation between resistivities,

Answer 27

Formation fluid is different from the drilling fluid

Question 28

Mise a la masse surveys

Answer 28

Geothermal Field
Pb Zn Cu
Au Pyrite

Question 29

Conductive Ore

Answer 29

Miss a La masse

Question 30

Mining and Econ Geol

Answer 30

?Electrical Mapping
?Mine Mapping
?Hydrocarbon mapping
?Extension of Ore bodies
?Base Metal w/ IP or EM

Mise a la masse
?Geothermal Field
?Pb-Zn-Cu
?Au-Pyrite
?Conductive Ore

Question 31

Structural

Answer 31

?Demarcation of Geol structures and Intrusives
?Geochronology of Rock Formations

Question 32

Hydrogeol

Answer 32

?Freshwater Resources

Question 33

Environmental and Engg

Answer 33

?Engg Test Drilling