Major crustal fault zone trends and their 

relation to mineral belts in the north-central 

Great Basin, Nevada 

By Brian D. Rodriguez, Jay A. Sampson, and Jackie M. Williams 

Open-File Report 2007-1115 

U.S. DEPARTMENT OF THE INTERIOR 

U.S. GEOLOGICAL SURVEY 
U.S. Department of the Interior 

DIRK KEMPTHORNE, Secretary 

U.S. Geological Survey

Mark D. Myers, Director 

U.S. Geological Survey, Reston, Virginia 2007 

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Suggested citation: 

Rodriguez, B.D., Sampson, J.A., and Williams, J.M., 2007, Major crustal fault zone 

trends and their relation to mineral belts in the north-central Great Basin, Nevada: 

U.S. Geological Survey Open-File Report 2007-1115, 17 p. 

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ii
Contents

Abstract.........................................................................................................................................1

Introduction ...................................................................................................................................1

Electrical Rock Properties .............................................................................................................3

Magnetotelluric Method.................................................................................................................3

Magnetotelluric Survey..................................................................................................................4

Resistivity Models..........................................................................................................................4

Geologic Correlations....................................................................................................................4

Conclusions.................................................................................................................................13

Acknowledgements .....................................................................................................................13

References Cited.........................................................................................................................13

Figures 

1. Index image of northern Nevada showing magnetotelluric profiles MT1 to MT9 ...............2

2. Index image of study area showing magnetotelluric profiles MT1 to MT9 ........................5

3. Two-dimensional resistivity models of magnetotelluric profiles MT1 to MT4 .....................6

4. Two-dimensional resistivity models of magnetotelluric profiles MT5 to MT9 .....................7

5. Deep conductor, electrical-strike directions for magnetotelluric profiles MT1 to MT9 .........9

6. Shallow conductor, electrical-strike directions for magnetotelluric profiles MT1 to MT9......11

 7. Deep crustal fault zone conductors in north-central Nevada .......................................12

iii
Abstract 

The Great Basin physiographic province covers a large part of the western United States 

and contains one of the world's leading gold-producing areas, the Carlin Trend. In the Great 

Basin, many sedimentary-rock-hosted disseminated gold deposits occur along such linear 

mineral-occurrence trends. The distribution and genesis of these deposits is not fully understood, 

but most models indicate that regional tectonic structures play an important role in their spatial 

distribution. Over 100 magnetotelluric (MT) soundings were acquired between 1994 and 2001 

by the U.S. Geological Survey to investigate crustal structures that may underlie the linear trends 

in north-central Nevada. MT sounding data were used to map changes in electrical resistivity as 

a function of depth that are related to subsurface lithologic and structural variations. 

Two-dimensional (2-D) resistivity modeling of the MT data reveals primarily northerly and 

northeasterly trending narrow 2-D conductors (1 to 30 ohm-m) extending to mid-crustal depths 

(5-20 km) that are interpreted to be major crustal fault zones. There are also a few westerly and 

northwesterly trending 2-D conductors. However, the great majority of the inferred crustal fault 

zones mapped using MT are perpendicular or oblique to the generally accepted trends. The 

correlation of strike of three crustal fault zones with the strike of the Carlin and Getchell trends 

and the Alligator Ridge district suggests they may have been the root fluid flow pathways that 

fed faults and fracture networks at shallower levels where gold precipitated in favorable host 

rocks. The abundant northeasterly crustal structures that do not correlate with the major trends 

may be structures that are open to fluid flow at the present time. 

Introduction 

Many sedimentary-rock-hosted disseminated gold deposits occur along linear 

mineral-occurrence trends in northern Nevada (Struhsacker and others, 1996). The distribution 

and genesis of these deposits along the Battle Mountain-Eureka (BME) and Carlin trends is not 

fully understood. In general, most geologic models suggest that regional structures played an 

important role in the spatial distribution of these deposits (e.g. Arehart and others, 1993; Ilchik 

and Barton, 1997; Radtke, 1985; Shawe, 1991; Sillitoe and Bonham, 1990; Tosdal and others, 

2000). To investigate crustal structures that may underlie these trends, nine profiles of 

magnetotelluric (MT) soundings were acquired between 1994 and 2001 (lines MT1 to MT9, 

fig. 1). Modeling of the MT data can be used to infer the deep resistivity structure of the crust. 

Such structures may reflect possible tectonic controls on the emplacement of mineral deposits 

along these linear trends, and so may be used to help improve critical gold endowment estimates 

in the north-central Great Basin. 

The attributes and location of major faults within the Northern Nevada Gold Province are 

relevant to crustal development and ore deposit models (Hofstra and Cline, 2000; Grauch and 

others, 2003). To better constrain the location and strike of major faults below cover, nine 

regional magnetotelluric (MT) sounding profiles were acquired in north-central Nevada 

(Williams and Rodriguez, 2000; 2001a; 2001b; 2001c; 2001d; Williams, and others, 2001a; 

2001b; 2001c). 

1
Figure 1. Index image of northern Nevada showing magnetotelluric (MT) profiles, MT1 

to MT9 (red line segments) modified from John and others (2003). Wide dotted lines 

show the major mineral trends and lineaments. Black outlined box in main image shows 

the study area (fig. 2). Dot-dash line shows the initial 87Sr/86Sr=0.706 isopleth (Sri) for 

the inferred edge of continental crust. Inset map shows the location of figure (box) and 

the outline of the Great Basin (heavy black line). AR = Alligator Ridge district; BC = 

Barneys Canyon deposit; BM = Battle Mountain district; BME = Battle Mountain-Eureka 

trend; C = Carlin mine; CL = Comstock lode; CT = Carlin trend; CVIL = Crescent 

Valley-Independence lineament; E = Eureka district; G = Getchell mine; GD = Goldfield 

deposit; GT = Getchell trend; H = Humboldt Range; I = Ivanhoe deposit; JC = Jerritt 

Canyon district; M = Midas deposit; MC = Mule Canyon deposit; PP = Paradise Peak 

deposit; S = Sleeper deposit; R = Rodeo deposit; REH = Ruby-East Humboldt 

metamorphic core complex; T = Tuscarora district; TN = Tenmile district; TO = Tonopah 

district.

2
Electrical Rock Properties 

Electromagnetic (EM) geophysical methods detect variations in the electrical properties 

of rocks, in particular electrical resistivity or its inverse, electrical conductivity. Electrical 

resistivity can be correlated with geologic units on the surface and at depth using lithologic logs 

to provide a three-dimensional (3-D) picture of subsurface geology. The resistivity of geologic 

units in the upper crust is largely dependent upon their fluid content, pore-volume porosity, 

interconnected fracture porosity, and conductive mineral content (Keller, 1989). Fluid content 

and conductive mineral content dominate the resistivity response within the upper to middle 

crust, and undersaturated melting conditions may be dominant near the base of the crust. Fluids 

within the pore spaces and fracture openings, especially if saline, can reduce resistivities in what 

would otherwise be a resistive rock matrix. Resistivity can also be lowered by the content of 

electrically conductive clay minerals, graphitic carbon, and metallic mineralization. It is common 

for altered volcanic rocks to contain replacement minerals that have resistivities ten times lower 

than those of the surrounding rocks (Nelson and Anderson, 1992). Fine-grained sediments, such 

as clay-rich alluvium, marine shale, and other mudstones, are normally conductive from a few 

ohm-m to a few tens of ohm-m (Keller, 1987; Palacky, 1987). Deszcz-Pan and others (2000) 

report that coarser-grained sediments, such as gravels and clean sands, are commonly moderately 

conductive (tens of ohm-m). Metamorphic rocks (non-graphitic) and unaltered, unfractured 

igneous rocks are normally moderately to highly resistive (a few hundreds to thousands of 

ohm-m). Carbonate rocks can have similarly high resistivities depending on their fluid content, 

porosity, and impurities (Keller, 1987; Palacky, 1987). Fault zones may be moderately 

conductive (tens of ohm-m) when comprised of rocks fractured enough to have hosted fluid 

transport and consequent mineralogical alteration (Eberhart-Phillips and others, 1995) or when 

comprised of fractured rock that has graphitic enrichment along former shear planes (Ritter and 

others, 2005). Higher subsurface temperatures cause higher ionic mobility that reduces rock 

resistivities (Keller, 1987; Palacky, 1987). Tables of electrical resistivities for a variety of rocks, 

minerals, and geological environments may be found in Keller (1987) and Palacky (1987). 

Magnetotelluric Method 

The MT method is a passive surface EM geophysical technique that measures the Earth's 

natural electric and magnetic field to investigate the electrical resistivity structure of the 

subsurface from depths of tens of meters to tens of kilometers (Vozoff, 1991). Worldwide 

lightning activity at frequencies of 10,000 Hz to 1 Hz and geomagnetic micro-pulsations at 

frequencies of 1 Hz to 0.001 Hz provide the majority of signal used by the MT method. The 

natural electric and magnetic fields propagate vertically into the earth due to the very large 

resistivity contrast between the air and the earth, which causes a vertical refraction of both fields 

at the surface (Vozoff, 1972). 

The natural electric and magnetic fields are recorded in two orthogonal, horizontal 

directions (the vertical magnetic field is also recorded). The resulting time-series signals are used 

to derive tensor apparent resistivities and phases by first converting them to complex cross 

spectra using Fourier transform techniques. Least squares, cross-spectral analysis (Bendat and 

Piersol, 1971) are used to solve for a tensor transfer function. For a two-dimensional (2-D) Earth, 

the MT fields can be decoupled into transverse-electric (TE) and transverse-magnetic (TM) 

modes; 2-D resistivity modeling is generally undertaken to fit both modes. When the geology 

satisfies the 2-D assumption, the MT data for the TE mode is assumed to represent the situation 

3
when the electric field is polarized along geologic strike, and the data for the TM mode when the 

electric field is oriented perpendicular to strike. The MT method is well suited for studying 

complicated geological environments because the electric and magnetic relations are sensitive to 

vertical and horizontal variations in resistivity. The method is capable of establishing whether 

the EM fields are responding to a 1-, 2-, or 3-dimensional subsurface. An introduction to the MT 

method and references for a more advanced understanding are contained in Dobrin and Savit 

(1988) and Vozoff (1991). 

Magnetotelluric Survey

One-hundred and eleven MT soundings were located along nine profiles (MT1 to MT9, 

fig. 2) of lengths varying from 20 to 150 km and site spacing that varied laterally from 1.5 to 

13.5 km. The single station recordings for profiles MT1 to MT9 are reported in Williams and 

Rodriguez (2000; 2001a; 2001b; 2001c; 2001d) and Williams and others (2001a; 2001b; 2001c). 

In 2004, MT data with vertical magnetic field recordings at stations 130 and 131 (Williams and 

Rodriguez, 2005) were collected to resolve ambiguity in previously published MT data (stations 

5A and 6A) where electrical strike directions that vertical magnetic field recordings (Williams, 

and others, 2001a; 2001b).

Resistivity Models

The observed data used in the 2-D resistivity modeling (figs. 3 and 4) were rotated to 

maximum and minimum impedance directions so that propagation modes for the signals were 

decoupled into transverse electric (TE) and transverse magnetic (TM) modes (Williams and 

Rodriguez, 2000; 2001a; 2001b; 2001c; 2001d; Williams, and others, 2001a; 2001b; 2001c). 

Resistivity model construction and results are described in detail in Rodriguez and Williams

(2001) for profiles MT1 to MT4 and in Rodriguez and Williams (2002) for profiles MT5 to 

MT9. 

Forward modeling was achieved using Phil Wannamaker’s 2-D finite-element integral 

solution program, PW2DIS (Wannamaker, 1989). We perturbed each 2-D model attempting to 

derive the best-fitting calculated response to the TE and TM mode observed data where the 

observed data indicated a 2-D response. However, we primarily attempted to fit the TM mode 

data where the observed data indicated a 3-D response (Wannamaker and others, 1984). Each 

2-D resistivity model is constructed by adjusting the resistivity values beneath the profile of MT 

stations, so that for all stations the calculated 2-D response agrees with the measured data. 

Geologic Correlations

In Rodriguez and Williams (2001; 2002), crustal high resistivity (300 to 1,000 ohm-m) 

was generally attributed to carbonates, intruded rock, plutonic rock, metamorphic rock, or 

Precambrian basement. Moderately resistive (30 to 300 ohm-m) rocks were inferred to be 

volcanic and/or clastic sedimentary rocks. Evidence supporting these interpretations, such as 

exposures of Cretaceous quartz monzonite, Tertiary granodiorite, or widespread re-crystallized 

carbonates, and broad magnetic highs supporting the presence of large concealed plutons near 

MT stations, are reported in Rodriguez and Williams (2001; 2002). Narrow, sub-vertical, 2-D, 

low-resistivity (1 to 30 ohm-m) conductors that penetrate to mid-crustal depths (5-20 km) are 

4
Figure 2. Index image of study area showing magnetotelluric (MT) profiles MT1 to MT9 

(thick black lines), acquired from 1994 to 2000 in north-central Nevada (fig. 1). The gray 

lines represent generally accepted mineral belts in north-central Nevada (AR = Alligator 

Ridge district; BME = Battle Mountain-Eureka trend; CT = Carlin trend; GT = Getchell 

trend). Numbered MT stations are shown as open circles for MT data that are 

two-dimensional (2-D) in character and open triangles for data that have 

three-dimensional character in the lower frequencies. Thin black lines are county 

boundaries. KGRA is Beowawe Known Geothermal Resource Area.

5
Figure 3. Two-dimensional resistivity models of magnetotelluric (MT) profiles MT1 to 

MT4. Depths are relative to ground surface. Black squares show stations whose MT 

data indicate three-dimensional character at lower frequencies. White arrows and 

serpentine black lines show deep model conductor that is inferred crustal fault zone 

(CFZ). Question marks indicate less certain model definition due to poor data quality. 

NNR is Northern Nevada Rift. Pz is Paleozoic rocks. Vertical exaggeration is 1.33:1, 

and physiographic locations are as in figure 2.

6
Figure 4. Two-dimensional resistivity models at no vertical exaggeration of 

magnetotelluric (MT) profiles MT5 to MT9. Depths are relative to ground surface. Black 

squares show stations whose MT data indicate three-dimensional character at the lower 

frequencies. White arrows and serpentine black lines show deep model conductor that 

is inferred crustal fault zone (CFZ). NNR is Northern Nevada Rift. Pz is Paleozoic rocks. 

Physiographic locations are as in figure 2.

7
best explained by major crustal-scale fault or fracture zones. The low resistivities can be caused 

by material associated with faulting or fracture filling, such as mylonitic breccia, brine-filled 

fractures, argillaceous alteration from hydrothermal fluids, substantial graphitic carbon 

associated with shearing, or fluid-deposited graphite derived from organic shales in the section 

(Wannamaker and others, 2002), or possibly some combination of these (Eberhart-Phillips and 

others, 1995). The width of the inferred crustal fault zones, in general, are not well constrained 

due to the combination of wide station spacing, the resolving power of diffusive EM, and the 

node spacing of the grid size used in the resistivity models (0.5-2 km). In the resistivity models 

(figs. 3 and 4), the overall range of widths at about 10 km depth varies from about 0.5 to 7 km

(after adjusting for projection widths). The actual conductor widths could be much narrower, and 

the exact cause of these conductors is inferred, not known. Not all crustal conductors were 

interpreted to be crustal fault zones. For example, the conductor (3 ohm-m) beneath stations 12 

and 19 (profile MT3, fig. 3) correlates with a known geothermal resource area (Beowawe 

KGRA, fig. 2). Conductors that are 3-D in character are attributed to other causes. For example, 

a large 3-D conductor (1 ohm-m) from 1 to 12 km depth between stations 27A and 28A (profile 

MT4, fig. 3) may also be from a geothermal system, a thick section of carbonaceous rocks, 

graphitized deep-water clastic Paleozoic rocks, or even some combination of these. Also, 

shallow 3-D conductors in the upper 2 km may be a combination of conductive (1 to 30 ohm-m) 

basin fill resting on shaley basement units, such as Devonian Pilot or early Mississippian 

Chainman Formations that have similar resistivities depending on their hydrocarbon maturity 

(Wannamaker and others, 2002). Finally, conductors that are 3-D in character may be due to a 

change in conductor strike direction or an intersection with another conductor with a different 

strike direction. 

Some of the narrow, sub-vertical, 2-D conductors mapped by the MT profiles that 

penetrate to mid-crustal depths (5-20 km) correlate reasonably well with the locations of the 

major trends, but most have preferred electrical strike directions that are at oblique angles to the 

trends (fig. 5). The majority of the narrow conductors have north and northeast strikes, but a few 

have west and northwest strikes. Previous investigations of crustal structures that may be related 

to the genesis of gold deposits along the northwest-striking Battle Mountain-Eureka (BME) and 

Carlin trends point to the strong gravity gradient along the BME trend (Grauch and others, 

1995), and the inferred fault zones under both BME and Carlin gold trends based on variations in 

the isotope geochemistry of granitoid intrusions (Tosdal and others, 2000). In earlier reports 

(Rodriguez and Williams, 2001; 2002) we inferred a major northwest-trending crustal fault zone 

along the BME trend based on data from an older MT data acquisition system that did not have 

the vertical magnetic field needed to resolve the 90o

 ambiguity in electrical strike directions 

inherent with principal impedance directions. In 2004, as part of a different survey (Williams and 

Rodriguez, 2005), key stations were reoccupied that had been previously used to define the 

major northwest-trending inferred crustal fault zone along the BME trend. After collecting the 

vertical magnetic field with the new MT system, it was clear that the wrong electrical strike 

direction (the 90o

 ambiguity) had been chosen. Figure 5 shows both the crustal fault zone strike 

directions determined with the new MT system (shown with red arrows) and the older MT 

system (that have the 90o

 ambiguity in principal impedance strike directions; shown with the 

double set of blue arrows). 

8
Figure 5. Deep conductor, electrical-strike directions for magnetotelluric (MT) profiles 

MT1 to MT9 (fig. 2). Arrow symbols show estimated 2-D strike directions for 2-D 

conductors at mid-crustal depths (5-20 km). Red arrows indicate strike directions 

constrained by vertical magnetic field. Blue arrows indicate strike directions that have 

90o

 ambiguity from impedance directions. Electrical strike resolution is about ±10o. The 

gray lines represent generally accepted mineral belts in north-central Nevada (AR = 

Alligator Ridge district; BME = Battle Mountain-Eureka trend; CT = Carlin trend; GT = 

Getchell trend). Numbered MT stations are shown as open circles for MT data that are 

two-dimensional (2-D) in character and open triangles for data that have 

three-dimensional character in the lower frequencies. Thin black lines are county 

boundaries. KGRA is Beowawe Known Geothermal Resource Area.

9
The crustal fault zones in the upper crust (1-5 km) show similar strike directions within the 

margin of error, ± 10o

, as the deeper fault zones (5-20 km) except near stations 25, 48, and 49 

(fig. 6). Near the Getchell trend, the shallow crustal fault zone strike directions of stations 48 and 

49 are subparallel with the mountain range where this mineral belt is found. In the Carlin trend, 

the shallow crustal fault zone strike direction at station 25 is either north-south or east-west (as 

defined by an old MT station with 90o

 ambiguity). 

An interpretation of the deeper crustal fault zone strike directions appears in figure 7 (red 

and green ellipses) where the inferred strike directions for the ambiguous strikes are guided by 

the unambiguous strike directions of nearby conductors (fig. 5) and nearby modeled resistivity 

structure (figs. 3 and 4). The ellipses in figure 7 illustrate the conductor widths and lengths 

based on the horizontal electromagnetic response of the modeled 2-D conductors. The conductor 

widths are based on the resistivity model widths (figs. 3 and 4) corrected for projection between 

the profile direction and the conductor strike direction (fig. 5). The modeled 2-D conductor 

lengths, by definition, are infinite in a 2-D resistivity model. However, each conductor length 

represented in figure 7 is derived from the conductivity-thickness product (conductance) that is a 

function of the depth limit of the modeled conductor, which in turn is constrained by the lowest 

usable measured frequency that indicates a 2-D conductor. Some of the inferred crustal fault 

zones in figs. 3 and 4 are not shown to penetrate as deep as other crustal fault zones because 

nearby 3-D conductors did not provide a resistivity contrast to resolve how deep the 2-D 

conductor penetrated the crust. The assumption is that the same principle that applies to how 

deep a crustal fault zone is resolved also applies to the minimum resolvable length of a crustal 

fault zone because the electromagnetic response of a conductor is a function of 3-D space. In 

order to resolve the maximum length of crustal fault zones adequate, nearby MT station coverage 

is needed. The only inferred crustal fault zones that are subparallel to the major trends (green 

ellipses in fig. 7) are located in the Carlin trend, Getchell trend, and Alligator Ridge district. All 

other inferred crustal fault zones (red ellipses) in figure 7 are perpendicular or oblique to the 

trends. 

Gravity and isotope data (Grauch and others, 2003) reveal northwest structural trends in 

basement rocks that reflect the deformational history of the region. The thick sections of 

deep-water clastic sediments in this area are prime candidates as source rocks for gold, with the 

Eocene Northeast Nevada Volcanic Field providing a major heat source to drive fluid circulation 

(Wannamaker and others, 2002). The proximity of several inferred crustal fault zones (fig. 7) to 

many major deposits (Goldstrike, Gold Quarry, Battle Mountain Complex, Getchell, Bootstrap, 

Marigold, Twin Creeks, and Meikle) suggests that subsurface fluid flow may have been 

significantly influenced by these fault zones. The correlation of the strikes of three inferred 

crustal fault zones with the strikes of the Carlin and Getchell trends and the Alligator Ridge 

district suggests they may have been the root fluid flow pathways that fed faults and fracture 

networks at shallower levels where gold precipitated in favorable host rocks. Some of the 

ore-controlling faults within the major trends are at large angles to the overall strike of the trends 

(Cline and others, 2005). Hence, dilation of oblique faults within trends due to translation, or 

dilation of faults between the trends at intersections with discordant crustal faults, may have 

influenced fluid movement. It is also possible that most of the crustal structures detected that do 

not correlate with ore-controlling fault zones are not representative of those that were open to 

fluid flow when the deposits formed. Rather, they may be structures that are open to fluid flow 

today. 

10
Figure 6. Shallow conductor, electrical-strike directions for magnetotelluric (MT) 

profiles MT1 to MT9 (fig. 2). Arrow symbols show estimated 2-D strike directions for 2-D 

conductors in the upper crust (1-5 km). Red arrows indicate strike directions constrained 

by vertical magnetic field. Blue arrows indicate strike directions that have 90o

 ambiguity 

from impedance directions. Electrical strike resolution is about ±10o

. The gray lines 

represent generally accepted mineral belts in north-central Nevada (AR = Alligator 

Ridge district; BME = Battle Mountain-Eureka trend; CT = Carlin trend; GT = Getchell 

trend). Numbered MT stations are shown as open circles for MT data that are 

two-dimensional (2-D) in character and open triangles for data that have 

three-dimensional character in the lower frequencies. Thin black lines are county 

boundaries. KGRA is Beowawe Known Geothermal Resource Area.

11
Figure 7. Deep crustal fault zone conductors in north-central Nevada. Ellipses illustrate 

estimated minimum widths and lengths based on deep sub-vertical 2-D conductors 

modeled (figs. 3 and 4) using magnetotelluric (MT) profiles MT1 to MT9 (fig. 2). Red 

ellipses illustrate crustal fault zones that are oblique to mineral belts, while green 

ellipses are for those that are subparallel. Orange-filled circles are disseminated gold 

deposits. Bold, orange-filled circles are major gold deposits. Blue-filled circles are 

pluton-related gold deposits. Yellow-filled circles are epithermal gold deposits. Gold 

deposit localities are from Brady (2005), Davis and Tingley (1999; 2005), Davis and 

others (2006), Driesner and Coyner (2006), and Wallace and others (2004). The gray 

lines represent generally accepted mineral belts in north-central Nevada (AR = Alligator 

Ridge district; BME = Battle Mountain-Eureka trend; CT = Carlin trend; GT = Getchell 

trend). Thin black lines are county boundaries.

12
Conclusions 

Magnetotelluric data collected along nine profiles show deep resistivity structures 

beneath the Battle Mountain-Eureka (BME) and Carlin gold trends in north-central Nevada that 

appear consistent with tectonic breaks in the crust that possibly influenced preferred fluid flow 

pathways for hydrothermal fluids. Two-dimensional resistivity modeling of the magnetotelluric 

data generally show resistive (30 to 1,000 ohm-m) crustal blocks broken by sub-vertical, 

two-dimensional conductors (1 to 30 ohm-m) that are indicative of large-scale crustal fault 

zones. These inferred regional fault zones trend predominately northeast-southwest, but also 

north-south and northwest-southeast, and extend to mid-crustal depths (5-20 km). Some gold 

deposits along these linear trends possibly were controlled by deep regional crustal fault systems 

that intersected them. 

The interpreted structure from these profiles provides constraints for future geologic 

interpretations of the genesis of gold deposits in the area of these mineral trends. The deep 

regional resistivity structure across the Carlin and BME trends may have direct implications for 

large gold resources in northeastern Nevada. The resistivity variations at mid-crustal levels 

reveal fault/fracture zones that may have influenced deformation in upper crustal rocks that 

localized fluid flow and precipitation of gold ores in the Northern Nevada Gold Province. 

Acknowledgements 

Data collection, processing, resistivity modeling, and preliminary interpretations in this 

project were supported by the U.S. Geological Survey Mineral Resources Program under the 

Nevada Gold and Metallogeny of the Great Basin projects. We are grateful for access to survey 

sites by the Bureau of Land Management, the Humboldt National Forest Service, Barrick Gold, 

Hecla Mining, Kennecott Minerals, Newmont Mining, and Placer Dome Mining. 

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