lecutre 5

Question 1

what are the 3 types of geophysical exploration

Answer 1

magnetic, seismic, gravity

Question 2

what is the name of the device used in magnetic geophysical exploration

Answer 2

magnomitor

Question 3

what is the name of the device used in gravity geophysical exploration

Answer 3

gravimeter

Question 4

how does the gravity anomoly show up at a reef

Answer 4

high - low

Question 5

magnetic and graivity geophysical readings are defined by what critque

Answer 5

low resolution

Question 6

another name for a vibrator used on land in seisimc is…

Answer 6

vibroseis

Question 7

what is the name of the vibraror used in seismic at sea

Answer 7

air gun

Question 8

what is the name of the seismic receiver used during seimic imaging on land

Answer 8

geophone

Question 9

what is the name of the seismic receiver used during seimic imaging at sea

Answer 9

hydrophone

Question 10

what is the name of a group of seismic receivers

Answer 10

array

Question 11

what are the three stages of seimic survey

Answer 11

acquisition, processing, interpretation

Question 12

what is a seismic trace

Answer 12

data gathered by one shot of a seismic wave

Question 13

what is a seismic profile

Answer 13

combination of seismic traces representing a cross section of subsurface structures

Question 14

what is a variable densitity display

Answer 14

represents seismic energy amplitude

Question 15

what is deconvolution

Answer 15

inverse filtering, processing combining the seismic energy spread out across the sub surface

pulse is natural spread out

pulse is filtered by different density rock layers

Question 16

what is geophysical imaging “migration”

Answer 16

a mathematical process to reconstruct the the reflector geometry from the reflected seismic energy

geometrical relocation needed because of reflections

Question 17

what is the bow tie effect

Answer 17

reflections occcuring from both sides of a syncline

reflections arrive at receiver at different times