Term
as wavelength goes up, the signal's ability to penetrate the ground _____, and resolution _____ 

Definition
as wavelength goes up, the signal goes deeper, and resolution goes down 


Term
as wavelength goes down, depth of signal _____, and resolution _____ 

Definition
as wavelength goes down, the signal can't go as deep, but resolution goes up 


Term

Definition
units of conductivity are 1/ohm 


Term
most rocks are poor conductors, so current is carried by ____ 

Definition
most rocks are poor conductors, so current is carried by fluids in pore water 


Term
most rocks are poor conductors, so _____ is carried by fluids in pore water 

Definition
most rocks are poor conductors, so current is carried by fluids in pore waters 


Term
in electrical surverys, low frequencies measure _____, while high frequencies measure _____ 

Definition
in electrical surveys, low frequencies measure conductivity while high frequencies measure dielectric constants 


Term

Definition
Archie's Law is
formation factor = F= (resistivity of rock)/(resistivity of pore water) = aΦ^{m}



Term
in Archie's Law, what does each symbol mean? 

Definition
in Archie's Law, formation factor = a*Φ^{m}
Φ is porosity. "a" and "m" are dependent on lithology 


Term
when we say "high frequencies" of electronic surveys, what range of frequencies are we talking about? 

Definition
when we say "high frequency" for electronic surveys, we are looking at 101000 MHz 


Term
the goal of examining dielectric properties 

Definition
the goal of examining dielectric properties is to establish a relationship between physical properties of a layer and the radar wave velocity in that layer 


Term
what is dielectric permittivity the same as? 

Definition
dielectric permittivity is the same as dielectric constant 


Term
dielectric constant is a measure of what? 

Definition
dielectric constant is the measure of a material's ability to hold a charge 


Term
dielectric permittivity has units of what? 

Definition
dielectric permittivity has units of farads. A farad is a measure of capacitiance. Capacitance is how much electric potential it takes to acheive one unit of charge. Or how much charge results from one unit of electric potential. 


Term
what property of materials relates how much electric potential leads to how much charge? 

Definition
dielectric permittivity aka dielectric constant aka relative permittivity is the property that has units of farads that relates how much electric potential leads to how much charge 


Term
if a material has a dielectric permittivity of one farad, what does that mean? 

Definition
if one volt (unit of electric potential) results in one columb (unit of charge) then a material has a dielectric permittivity of one farad 


Term
magnetic permittivity is a measure of what? 

Definition
magnetic permittivity is a measure of how much a material gets magnetized when it is placed in a magnetic field 


Term
what property of matierals has units of Henrey's? 

Definition
magnetic permittivity has units of Henreys 


Term
what are units of magnetic permittivity 

Definition
the units of magnetic permittivity are Henrey's 


Term
in a vaccum, radar waves move as fast as ____ 

Definition
in a vaccum, radar waves move as fast as the speed of light 


Term
what is the equation for radar wave velocity? 

Definition
the equation for radar wave velocity is
V= c/(square root of (εr*μr))



Term
what is the skin depth equation? 

Definition


Term

Definition
skin depth is the depth that waves will travel in a given rock 


Term
the thing about GPR is that the _____ are much higher, so the ____ are much _____. 

Definition
the thing about GPR is that the velocities are much higher, so the wavelengths are much shorter 


Term
I do GPR and acoustic surveys in a granite layer.
In Survey one, the wavelength for my waves is 50 meters.
In Survey two, the wavelengths for my waves is .6 meters.
Which survey is GPR, and which is acoustic? 

Definition
GPR has shorter wavelengths
Acoustic has longer wavelengths
Survey 1 is acoustic
survey 2 is GPR 


Term
relationship between vertical resolution and wavelength 

Definition
the relationship between vertical resolution and wavelength is that vertical resolution is about a quarter of wavelength 


Term
as you use GPR to anaylze a system with an uneven boundary layer, what is an issue that will create more error? 

Definition
scattering and focussing are problems you run into when you use GPR to anaylze a system with an uneven boundary layer 


Term
what property of materials does an induced potential survey measure? 

Definition
an induced potential survey looks at the chargeability of materials 


Term
what electricity survey examines the chargeability of materials? 

Definition
induced potential surveys look at the chargeability of materials 


Term
what is the application of induced potential electrical survey? 

Definition
induced potential surveys are used for base metal exploration 


Term
how do you do an induced potential survey? 

Definition
an induced potential survey is done by applying an electric field to the ground, then turning it off. then you measure if the ground is still conducting electricity 


Term
in an induced potential survey, the time that rocks are still charged after you turn off the electric field is on the scale of _____ 

Definition
in an induced potential survey, rocks will be charged after you turn off the electric field on a scale of seconds 


Term
in an induced potential survey, the distance that the charge travels after you turn of the electric field is a function of _____ 

Definition
in an induced potential survey, you apply an electric field then turn it off. The distance that the charge travels through the ground afterwards is a function of frequency 


Term
why can't you use a standard resistivity array for a induced potential method? 

Definition
you need to record the charge of the ground for several seconds, which a standard resistivity array cannot do 


Term
what electrical technique do we use for base metal exploration? 

Definition
we use induced potential for base metal exploration 


Term
what does the spontaneous potential electrical survey look for? 

Definition
the spontaneous potential electric survey looks for an oxidizing/reducing boundary 


Term
what is the application of the spontaneous potential electric survey? 

Definition
the spontaneous potential electric survey is used for mineral exploration 


Term
what electric survey is used for mineral exploration? 

Definition
spontaneous potential is the electric survey used for mineral exploration 


Term
what signal does the magnetotelluric electrical method look at? 

Definition
the magnetotelluric electrical method is looks at electric flow caused by charged particles flowing from the ionosphere 


Term
the magnetotelluric method has what application? 

Definition
the magnetotelluric method is used to look at crustal/lithosphere scale studies. It is especially good at looking under basalts in sedimentary basins 


Term
what electrical method is used for crustal/lithosphere scale studies? 

Definition
the magnetotelluric method is used for crustal/lithosphere scale studies 


Term
with the magnetotelluric methods, you need a base station with _____ 

Definition
for the magnetotelluric method, you need a base station with two electrodes at 90° from one another. This is how you measure variations in voltage 


Term
for _____ surveys, you have a base station with electrodes at 90° to measure variations in voltage 

Definition
for magnetotelluric surveys, you have a base station with electrodes at 90º to measure voltage 


Term
definition of conductivity 

Definition
conductivity is defined as "the degree to which a material conducts electricity" 


Term
conductivity calculated as _______ 

Definition
conductivity is calculated as "the ratio of electric current density to the electric field that generated them" 


Term
this property is defined as "the ratio of current density to the electric field" 

Definition
conductivity is defined as "the ratio of current density to the electric field" 


Term
this property is the reciprocal of resistivity 

Definition
conductivity is the reciprocal of resisitvity 


Term
what is the difference between active and passive resistivity/electromagnetic surveys? 

Definition
active surveys: you generate a current and measure how it travels through the subsurface
Passive surveys: you measure natural currents 


Term
what is induced polarization? 

Definition
induced polarization is when you apply a current to the ground and then make measurements 


Term
electromagnetic surveys all consist of what? 

Definition
all electromagnetic surveys involve generating a magnetic field, which generates an electric field which you measure with coils 


Term
ohm's law states that ____ 

Definition
ohm's law states that the current flowing through a material is proportional to the potential applied to that material
V is proportional to i
V is voltage, a measure of potential
i is current flow 


Term
which law states at V is proportional to i


Definition
ohm's law states that V is proportional to i
V is voltage, a measure of potential
i is curent 


Term
what is the constant of proportionality between V and i? 

Definition
the constant of proportionality between V and i is resistance, denoted as R. resistance has unit of ohms
V=R*i 


Term
resistance is related to potential and current how? 

Definition
resistance is the proportionality constant between potential and current.
V=i*R 


Term

Definition
units of resistance are Ohms 


Term
the law of cables states _____ 

Definition
the law of cables states that resistance is proportional to the length of cable it is running through (L) and inversely proportional to the crosssectional area of the cable it is running through. 


Term
what is the constant of proportionality for resistance and length/area 

Definition
the constant for proportionality of resistance and length/area is resistivity, denoted as ρ
ρ = (R*L)/A



Term

Definition
units of resistivity are ohmmeters 


Term
resistivity is the constant of proportionality between ____ and ____ 

Definition
resistivity is the constant of proportionality between resistance and length/area 


Term
what is the connection between length of a current flow line and the time it takes the signal to be communicated? 

Definition
the longer the current flow line, the longer it takes the signal to be communicated 


Term
what kind of diagram could you look at to see how relatively long it takes different current paths to go from one point to another 

Definition
a current flow diagram shows current paths. the longer currents paths take longer to communicate signal compared to shorter ones 


Term
You are looking a current flow diagram. The current paths goes to a new layer and bends towards the vertical. What do we know about the lower layer? 

Definition
when a current enters a new layer and bends towards the vertical, the new layer is higher resisitivity 


Term
what is the change in resistivity data as electrodes are moved farther and farther away in a two layer system? 

Definition
as electrodes get farther and farther away, apparent resistivity gets closer and closer to the resisitivity of the lower layer 


Term
in a current flow diagram, path density is related to _____ 

Definition
in a current flow diagram, high path density means high current density 


Term
what is the biggest application of resistivity surveys 

Definition
the biggest application of resisitivity surveys is finding how much water is in different layers, which we can deduce permeability from 


Term
resistivity surveys don't give you distinct layers, they give you _____ 

Definition
resitivity survey's don't tell you what layers are present, they simply give you pseudosections 


Term
what kind of surveys always involve predictive modeling after you get information from the earth? 

Definition
Resistivity studies only give you apparent velocity and pseudosections, so you have to use predictive modeling to see what the information is actually telling you 


Term
after you get information from the earth from resisitivity surveys, this is the next step 

Definition
you always finish resisitivity surveys with predictive modeling 


Term
what is the difference between forward and reverse modeling? 

Definition
forward modeling is making a model based on what you expect to see before you survey the earth.
inverse modeling is looking at the data from a survey and finding a model to match 


Term

Definition


Term
is spontaneous potential active or passive? 

Definition
spontaneous potential is passive 


Term
what do you need for spontaneous potential? 

Definition
the setup for spontaneous potential is simply two electrodes 

