united states department of the interior lynn r. … · figure 1. recorder and shot locations for...

UNITED STATES DEPARTMENT OF THE INTERIOR

GEOLOGICAL SURVEY

A seismic Study of Yucca Mountain and Vicinity, Southern Nevada; Data Report and Preliminary Results

Lynn R. Hoffmanl and Walter D. Mooney2

Open-File Report 83-588

Prepared in cooperation with the Nevada Operational OfficeU.S. Department of Energy

(Interagency Agreement DE-AI08-78ET44802)

The report is preliminary and has not been reviewed for conformity with U.S Geological Survey editorial standards and stratigraphic nomenclature.

1. U.S.G.S., Pasadena, CA 911252. U.S.G.S., Menlo Park, CA 94025

1984

CONTENTS

Page Abstract ............................................................. 3Introduc tion ......................................................... 4Acknowlegments ....................................................... 7Instrumentation and Field Operations ................................. 8

Seismic Recorders ............................................... 8Deployment ...................................................... 8Data Reduc tion .................................................. 8Logistics ....................................................... 9

Observations ......................................................... 10Seismic Profiles ................................................ 10Traveltime Delays ............................................... 16Rock Velocities ................................................. 16

Interpretation ....................................................... 19P-wave Delay Data ............................................... 19Shot Point 4 Profile ............................................ 21Shot Point 3 East Profile ....................................... 24Summary ......................................................... 24

References ........................................................... 25Appendix A: Seismic Recorder Locations .............................. 26Appendix B: Master Shot List and Team-Shot Data Sheets with

Tape Grade Scale ........................................ 32Appendix C: First Arrival Times ..................................... 45

ILLUSTRATIONS

Figure1. Recorder and shot locations for nuclear event deployments ....... 52. Recorder and shot locations for shot point 4 deployment ......... 63. Nevada Test Site shot point 1 - Normalized record sections ...... 114. Nevada Test Site shot point 2 - Normalized record sections ...... 125. Nevada Test Site shot point 3 - Normalized record sections ...... 136 T-X/6 (sec) traveltimes for shot points 1 and 3 with 10 mgal

Bouguer gravity contours (2.67) reduction velocity .............. 147. Nevada Test Site shot point 4 - Filtered 2-10 Hz record section . 158. Velocity model for P-wave delay data ............................ 179. Ray diagram for shot point 4 data ............................... 20

10. Velocity model for shot point 4 data ............................ 2211. Traveltime curve and crustal velocity model for southern Nevada . 23

TABLE

Table 1: Density-velocity relationship .............................. 19

PLATE

Plate 1: Nevada Test Site numbered recorder site locations

ABSTRACT

From 1980 to 1982, the U.S. Geological Survey conducted seismic refraction studies at the Nevada Test Site to aid in an investigation of the regional crustal structure at a possible nuclear waste repository site near Yucca Mountain. Two regionally distributed deployments and one north-south deployment recorded nuclear events. First arrival times from these deployments were plotted on a location map and contoured to determine traveltime delays. The results indicate delays as large as 0.5 s in the Yucca Mountain and Crater Flat areas relative to the Jackass Flats area. A fourth east-west deployment recorded a chemical explosion and was interpreted using a two-dimensional computer raytracing technique. Delays as high as 0.7 s were observed over Crater Flat and Yucca Mountain. The crustal model derived from this profile indicates that Paleozoic rocks, which outcrop to the east at Skull Mountain and the Calico Hills, and to the west at Bare Mountain, lie at a minimum depth of 3 km beneath part of Yucca Mountain. These results confirm earlier estimates based on the modeling of detailed gravity data. A mid-crustal boundary at 15 + 2 km beneath Yucca Mountain is evidenced by a prominent reflection recorded beyond 43 km range at 1.5 s reduced time. Other mid-crustal boundaries have been identified at 24 and 30 km and the total crustal thickness is 35 km.

INTRODUCTION

During the spring of 1980 and 1981, the U.S. Geological Survey conducted preliminary seismic refraction studies in the vicinity of Yucca Mountain, Nevada. The purpose of the study was to determine variations in the near-surface velocity structure of the upper crust which will aid in assessing the feasibility of nuclear waste storage in this area. These variations consist of changes in depth to a prevolcanic (pre-Tertiary) surface and in tne thickness of near-surface lithologic units. In combination with other geophysical data, these variations can be used to derive cross sections of the uppermost crust that are important to structural, tectonic, and hydrologic analysis of the area.

Portable seismographs were deployed near Yucca Mountain and three separate nuclear events were recorded. Figure 1 shows the locations of the recording equipment and the nuclear events that were used as seismic sources. To better constrain the velocity structure of the uppermost crust and determine field parameters for a future detailed study, an east-west profile was deployed in April 1982. It extended from a shot point southeast of Beatty, Nevada, across Yucca Mountain to the Skull Mountain area of the Nevada Test Site. Figure 2 shows the recording locations and the shot point for this additional deployment. Data with clear first arrivals and a high signal to noise ratio were recorded from all four sources. P(compressional)-wave arrival times can be determined on the records to an accuracy of 0.02 s.

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Figure 1. Recorder and shot locations for nuclear event deployments.Recorder site locations are indicated by dots, nuclear events by stars, selected drill holes by triangles, and shallow seismic refraction profiles by double circles. B-B* indicates the referenced gravity study of Snyder and Carr (1982).

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Figure 2. Shot point 4 recorder locations. SP 4 is the shot point location. Recorder site locations are indicated by dots. Line B-B 1 as in figure 1.

ACKNOWLEDGMENTS

This investigation was initiated by J. H. Healy; we are grateful to him for his encouragement throughout all stages. We wish to express our appreci ation to S. K. Gallanthine, W. M. Kohler, W. J. Lutter, J. N. Roloff, V. D. Sutton, A. W. Walter, and S. S. Wegener for their diligent work in recording data from the nuclear events. Thanks are extended to J. M. Bonomolo, E. E. Criley, R. P. Meyer Jr., R. M. Kaderabek and G. A. Molina for their field work in connection with the fourth deployment. A. L. Boken's graphical ray tracing and R. 0. Colburn's two-dimensional computer raytracing of the Beatty-Skull Mountain line is greatly appreciated. H. W. Oliver and D. B. Snyder provided valuable advice and assistance in planning the field work at the Nevada Test Site, and have suggested improvements to the text.

INSTRUMENTATION AND FIELD OPERATIONS

SEISMIC RECORDERS

One hundred portable seismic recorders, each weighing approximately 40 pounds and powered by two 6-volt rechargeable batteries, recorded the data in FM-analog form on 30-minute cassette tapes. The instruments were divided into five sets of 20 units each. Five observers were responsible for the mainte nance, deployment and accurate site location for each of the 20 units in their designated set.

These seismic recorders allow much flexibility in deployment. They do not record continuously but are preprogrammed with up to ten recording times. The recording time window can vary depending on how many times the unit is to record for each thirty-minute side of tape. Instrument electronics begin warming up ten minutes prior to each recording time. Prior to the expected energy arrival time, the unit will perform a geophone release, an amplification check and a calibration sequence of 1, 10, 100 and 1,000 mv, with a 10 Hz signal. These are recorded on the cassette and can be referenced during data processing for the evaluation of performance quality of the instrument. Following the calibration sequence, the unit begins to record data. The geophone is a vertical-component velocity transducer with a natural resonance frequency of two cycles per second and a motor constant of one volt per cm/s. Three data channels are used, each with a different, pre-set amplifier gain. Maximum gain is approximately 104 db; minimum gain is 0 db. In addition, 1RIG-E time signals from the internal chronometer and WWVB radio time signals are recorded (Healy and others, 1982).

DEPLOYMENT

Since nuclear events do not always occur as scheduled, it was necessary to program several large recording windows at estimated event times. These estimated times were essentially guesses based on a combination of the scheduled time of the event and experience from past recording attempts. Due to the limited amount of tape in each recorder and the lack of field mobility during times of probable nuclear events, two units were placed at each location with alternating recording times. This limited the data coverage to fifty locations, but resulted in the successful recording of the first two nuclear events. Continuous reprogramming of the equipment and added mobility in the field area made it possible to occupy 100 sites to record the third event.

A second complication resulting from the nuclear event delays was that the batteries on the recorders would run down, often causing instrument malfunctions. Where normally 100 sites are occupied with a 90% data recovery,, the data return for these nuclear event recordings was less than 70%.

The shot time for the fourth deployment was selected by the seismic experiment field staff and the recorders were programmed accordingly. A 2,480-pound charge of ammonium nitrate was fired below the water table at a location southeast of Beatty, Nevada. Data recovery in this instance was 85%.

DATA REDUCTION

Following each deployment, recording units were retrieved and several preliminary data processing steps were taken. All information pertaining to the operation of the seismographs was entered on the team-shot data sheets (Appendix B). Shot information for the nuclear events was obtained through personal communication with the Nevada Test Site Control Point. The shot time for shot number four was picked from the shot record, a paper tape showing shot time and shot detonation. Recorder locations and elevations were deter mined from the topographic maps. Chronometer corrections were calculated in order to adjust for the clock drift at shot time. These data were entered into various computer files and used in conjunction with recorder information for digitizing. Following accuracy checks for errors in timing and site locations, the cassette tapes were digitized. Calibration settings were used to compare data channels while digitizing and performance quality of the recorder was graded (Healy and others, 1982). Trace normalized record sections were plotted using the standard reduction velocity of 6 km/s. (In trace normalized plots, all seismograms in a record section have their maximum amplitude set to an equal trace width, thus producing a uniform appearance.) Some data from shot points 1 and 2 were plotted as fan shots with the first station as zero distance and successive stations as a function of distance from that point. All lines are unreversed in that a shot was not fired from the opposite direction. Data from shot point A were filtered to remove some high frequency noise, and the data from some sites were omitted due to overlapping traces.

LOGISTICS

When this project was initiated, very few roads penetrated the Yucca Mountain area, making adequate coverage of the proposed repository site difficult. As the Yucca Mountain investigations continued more roads were constructed. By the 1982 deployment, the area could be covered fairly well and the east-west deployment line across the mountain was possible.

Due to this continuous road construction, the indicated roads on topographic maps for Yucca Mountain and vicinity are very outdated. Recorder stations could not be as easily located as in normal field operations. Many sites had to be located using a Brunton compass, which tends to reduce the accuracy in determining the location of the site. Where normally station locations are accurate to 25 feet, those along the unmapped roads have a larger error margin of 50 to 100 feet. All locations are indicated on Plate 1, which is at a scale of 1:250,000. Location numbers on this plate are also indicated on the record sections.

10

OBSERVATIONS

SEISMIC PROFILES

Data for the first nuclear event, shot point 1, were collected in a short north-south line and an extended east-west fan array (Figure 3). The second nuclear event, shot point 2, resulted in a northeast-southwest line of data and an east-north-east to west-southwest fan array (Figure 4). These data are of greatest value presented as delay time observations for apparent velocity analysis.

Some of the most useful data from the nuclear event recordings were obtained from the third nuclear event, shot point 3. Two lines deployed to the east and west of Yucca Mountain provide the closest data to the proposed repository (Figure 5). The distance from the source at Pahute Mesa to Yucca Mountain is approximately 50 km, and at this distance all first arrivals are basement (Pg) arrivals. The eastern profile, from Yucca Mountain to Death Valley Junction, was recorded at a distance of 48 to 110 km. Significant traveltime variations in the first-arrival curve suggest delays in near- surface rocks that amount to 0.5 s in the Yucca Mountain area. In addition, clear reflections from the mantle and midcrust indicate layering within the crust beneath Yucca Mountain. The western profile for shot point 3, from Yucca Mountain to the Amargosa Desert, was recorded in the distance range of 52 to 86 km. The data along this profile also indicate 0.5 s delays in the Yucca Mountain area and the northern data show a lower dominant frequency than those taken further south. This is due to the greater seismic attenuation at the sites above thicker sections of tuff.

First arrival times (Appendix C) for shot points 1 and 3 were plotted on a location map in order to contour the reduced traveltimes in the area of Yucca Mountain. Some recorder locations were occupied for both events which put better constraints on the traveltime correlation by enabling comparison of arrival times from the two events. The larger delay times in the vicinity of Yucca Mountain and Crater Flat are interpreted to be due to the thicker section of low velocity layers (e.g., ash-flow tuffs and Cenozoic volcanic layers) in that area . Figure 6 illustrates these delays and compares them with the Bouguer gravity anomalies (Healey and others, 1980). Traveltime delays of 1.2 s or larger generally correlate with Bouguer gravity values of -140 to -170 mgal, indicating that both the seismic and gravity data were affected by low velocity, low density volcanic material.

Data for shot point 4 (Figure 7), the chemical explosion near Beatty, Nevada, were recorded to a distance of 65 km from the shot point. Average station spacing along this profile was 1 km. The first arrivals are delayed over Crater Flat and Yucca Mountain by as much as 0.7 s relative to Bare Mountain. In addition to clear first arrivals, a prominent reflected (secondary) arrival was recorded beyond 40 km range.

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TRAVELTIME DELAYS

Since all of the P-wave arrivals are from a nearly horizontal refractor, the velocity structure between that depth and the recording stations will largely determine the relative difference in traveltime between neighboring stations. For example, considering neighboring stations at identical distances from the source, the station located on outcropping Paleozoic rocks will record significantly shorter traveltimes than one located on a thick sequence of ash- flow tuff due to the lower intrinsic velocity of the latter rocks relative to the former. These differences in traveltimes can be clearly seen in the contour map of reduced traveltimes in the study area (Figure 6).

Since the magnitude of the delay is proportional to both the depth of the horizontal refractor and the thickness of low velocity layers beneath a given station, we can estimate this thickness by combining the observed delay times with other geophysical data. We have found that the observed delay times fall into three groups:

1) 1.4 to 1.2 s, large delays over Crater Flat and Yucca Mountain2) 1.2 to 0.8 s, moderate delays over Jackass Flats3) 0.8 to 0.4 s, small delays over Skull and Bare Mountains

These three groups correspond to the presence of thick low velocity layers, moderately thick low velocity layers and a very thin to nonexistent low velocity layer, respectively (Figure 8).

Rock Velocities

Some knowledge of the velocities of the rocks within the study area is required in order to make use of the P-wave delay times to infer the near- surface structure. Four sources of information were used to estimate the rock velocities: local geologic studies, seismic refraction surveys, borehole measurements, and the subsurface density distribution as inferred from modeling of detailed gravity data.

The local geology (Christiansen and others, 1977; Snyder and Carr, 1982) indicates that at least three main rock types must be considered: Precambrian and Paleozoic clastic, metamorphic, and sedimentary rocks; Cenozoic ash-flow tuffs; and Cenozoic volcanics and alluvium. The velocities of these types of rocks are known to vary from about 1.0 km/s to over 6.0 km/s and this wide range of velocities is reflected in the one-second spread in the values of the bserved P-wave delay times in the study area (Figure 8). Seismic refraction surveys that have been conducted in the areaprovide important information on the velocities of individual rock types (L. W. Pankratz, 1982; figure 1). These profiles at the easternmost end of this study show velocities in the alluvium of from 1.0 to 2.2 km/s, while the ash-flow tuffs are characterized by a velocity of 2.6 to 3.2 km/s. A layer presumed to be altered argillite has a velocity of from 3.8 to 4.5 km/s and the lowest layer has a velocity of 4.4 to 5.1 km/s. The lowest layer detected is presumed to be the top of a granitic body in the profile area. The velocity in the basement refractor at

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about 4 km depth is estimated to be 6.0 to 6.15 km/s based on the refraction profiles reported by Johnson (1965) and confirmed by the profiles reported here (Figures 3, 4, 5, and 7).

Additional information has been obtained from borehole velocity measure ments made at two 1,830 m (6,000 ft)-deep holes on the eastern flank of Yucca Mountain. The velocity measurements in holes Gl and HI (Figure 1) show velocities in the range of 3.3 to 4.2 km/s in the 400 to 1,830 m (1,300 to 6,000 ft) interval. Furthermore, it was determined that the one-way traveltime to the bottom of HI is 0.6 s, an average velocity in the hole of 3.0 km/s (D. C. Muller, written communication, 1982).

Whereas the typical velocities of the various rock types have been determined from the foregoing seismic measurements, the distribution of rock types was estimated by modeling of the regional gravity (Ponce, 1981; Snyder and Carr, 1982). These comprehensive studies have proposed crustal structures in the study area which are unlikely to be significantly improved upon until additional deep drilling or seismic refraction work is done. In choosing rock velocities, therefore, care has been taken to use values which are reasonable for the densities shown in the gravity models.

19

INTERPRETATION

The upper crustal structure in the Yucca Mountain area has been inferred from both the seismic P-wave delays (Figures 3, 4, and 5) and the unreversed refraction profile from shot point 4 (Figure 7). Since the present seismic data alone is insufficient for deriving the crustal structure in this geologically complex region, we have relied heavily on existing models and have modified these to obtain new, closely related models in agreement with the seismic observations. The results provide new details on the structure in the study area, and have been used to define the need for further seismic investigations.

P-WAVE DELAY DATA

The seismic P-wave delay data from Crater Flat to Skull Mountain have been interpreted using the B-B 1 crustal density section of Snyder and Carr (1982; Figure 9) as a basis. Since the P-wave data reaches as far as Skull Mountain (i.e., beyond section B-B 1 , figure 2), their model was extrapolated an additional 15 km to the east. The densities in their model were converted to velocities with close reference to the available seismic information, as shown in Table 1.

TABLE 1DENSITY - VELOCITY RELATIONSHIP

Density Velocity (g/c3) (km/s)

1.8 2.02.0 2.22.3 3.22.4 4.62.6 5.72.7 5.8

6.1

The P-wave delay times associated with this velocity model were calculated by raytracing critically refracted rays through the model. A velocity of 6.1 km/s was used for the refracting medium located at a depth of 2.3 km below sea level (3.6 km below the surface; Figure 8). The comparison of observed and calculated delay times indicates that the velocity model is a reasonable one; the observed delay times clearly confirm the greater depth to the pre-volcanic rocks beneath Crater Flat and Yucca Mountain. The main discrepancy between the observed and calculated values occurs on Crater Flat where the observed delay is greater than that predicted by the model. This indicates a westward increase in either the depth of the pre-volcanic layer or in the amount of low velocity near-surface materials. We note on the contour map of Figure 6 that the maximum delay time on Crater Flat, 1.4 s, is matched by an equal delay time on Yucca Mountain at a location 5 km north of the profile line B-B 1 . This suggests that local variations in thickness of the low velocity tuffs is the cause of the 1.4 s delay on Crater Flat, rather than a systematic westward deepening of the pre-volcanic layer.

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velocity model provides the

model traveltimes

(solid line,

top)

which have be

en adjusted to

fi

t th

e observed

time

s (open circles).

Reflected, re

frac

ted,

an

d diffracted rays

have been considered.

The final

model was

obtained by iteratively

adjusting velocities and

boundary depths in the

star

ting

model

derived from the

crustal density section of Snyder an

d Carr

(198

2).

Model

parameters ar

e given in Figure 10

.

NJ

o

21

Shot Point 4 Profile

The refraction profile from shot point 4 (near Beatty) to Skull Mountain demonstrated the feasibility of recording clear refracted arrivals to a distance of 65 km in an area considered to be in a "bad data" region for seismic reflection profiling. Since the profile is unreversed, a unique model cannot be derived with the present information, despite the high signal-to- noise ratio of the data. The data does, however, give additional control on the existing density model of the upper crust obtained from the interpretation of gravity data.

The method of interpretation used for shot point 4 data was similar to that applied to the P-wave delay data; the B-B* crustal section of Snyder and Carr (1982) was converted into a velocity model and traveltimes of compressional waves were calculated through this model, in this case by two-dimensional computer raytracing. A comparison of observed and theoretical traveltimes (Figure 9) shows that the velocity model provides a close fit to the data, the error being +0.05 s in most places. The ray diagram shows that the arrivals to stations on Crater Flat and Yucca Mountain reach their bottoming points beneath Bare Mountain, and the arrivals to Jackass Flats bottom beneath Yucca Mountain. The diagram also makes clear that additional shot points at 20, 40, and 60 km on the distance scale would provide excellent seismic reversal coverage along the refracting and reflecting horizons. The traveltimes of the prominent secondary phase recorded on this profile (Figure 7) is fit by reflections from a boundary at a depth of 15 +_ 2 km below sea level.

The velocities and layer boundaries used to compute the theoretical traveltimes in two alternative models are shown in Figure 10. In considering this diagram, it should be understood that the method of computation requires that boundaries be included wherever a change in velocity or velocity gradient is desired. Since the depth to a boundary can often be traded off against velocity at that boundary, the depth to some boundaries is non-unique, and some boundaries are included only to allow a change in the velocity gradient (e.g., the boundary at a depth of 5 km in Figure 10). To distinguish the boundaries with first order geologic importance from those that are mainly the product of the analysis method, the former boundaries are shown as heavy solid lines and the latter by light solid lines. The two heavy lines correspond to the volcanic/pre-volcanic boundary and to the major mid-crustal boundary at a depth of 15+2 km. The depth estimates to pre-volcanic rocks are 3.2 km (10,500 ft) beneath eastern Crater Flat and 1.1 km (3,650 ft) beneath Jackass Flats. Whereas the gravity model of Snyder and Carr (1982) shows a single east-dipping contact between Bare Mountain and Crater Flat, located 3 km east of outcropping Paleozoic rocks on Bare Mountain, the velocity model shows a distinct 2.5 km-wide bench (down-dropped block?) at a depth of 1.6 km (5,250 ft). The apparent velocity of the pre-volcanic layer increases from about 5.7 to about 6.0 km/s or higher within the first two kilometers. The absolute velocity of the basement remains uncertain with the present unreversed seismic data. A north- south reversed profile within Crater Flat is planned in order to resolve this uncertainty and to confirm the velocity-depth structure.

UJ J UJ Q_

LU

Q

2.

o- 10

-

15- C

i

BE

AT

TY

B

AR

E

MT

N

5.3

^-3

5.7

69 .c.

(6.4

)

6.3

(6.5

0)

6.3

(6.5

)

6.35

J655

)_ _

__

__

_

i)

i i

YU

CC

A

CR

AT

ER

M

TN

F

LA

T_

__

__

__

__

__

_

^<

~-^

t2

^ y2.2

/ 1>

^" "

J o

-^\

7X

\46

4-8

/

\D.t

\R7

1

\

/

(6.4

) ^'X

5.

82

' /

~~~

6.3(

6.5)

2

6.

3(6.

4)6

.3(6

.5)

6.3

(6.4

)

6.35

*-

*"

6.35

"*

**

(6 5

5)

fe-4

5)

I i

20

DIS

TA

NC

E

i i

i

JAC

KA

SS

F

LA

TS

S

KU

LL

MT

N

.2

/2.0

.2.2

_ ,

2*

2 A

-^N

TS

MD

5

5.7

*S

7 /

/»

« /

fi ?

// '

(6.3

) 6.

3 6.3

(6.3

)6.3

6.3

6.35

_ J

6_35

1_ _

__

__

__

__

__

_ 1

6.35

1

i i

I40

60

(K

M )

Figu

re 10

. Crustal

velo

city

mo

del

derived

from

sh

ot point

4 da

ta.

Average

layer

velocities are

indicated

in km

/s.

Solid

lines

are

layer

boundaries,

and

dashed lines

are

alte

rnat

ive

boundary depths

calc

ulat

ed fo

r th

e av

erage

laye

r velocities in parentheses.

The

heavy

soli

d li

ne ab

ove

a depth

of 5

km is

the

volcanic/pre-

volcanic bo

unda

ry.

The

mid-crustal

boun

dary

below

15 km

is

indi

cate

d by a

heav

y line where

the

depth

is controlled by

the

seis

mic

data

(c

.f.,

Figure 9)

. Th

e depth

to pr

e-vo

lcan

ic

rock

s (v

eloc

ity

greater

than

5.

0 km

/s)

is 3.2

km (10,500

ft)

bene

ath

eastern

Crater Fl

at.

10 ro

NTS SHOT POINT 3 EAST PROFILE______i____i____i____i_______i

23

0 LJC/)

<3 i

00

-Direct wave v through volcanics

Pg (basement)

40 80 120 160

DISTANCE (KM)

200

io-

i _x 20-f-Q. LJ

° 30-

4O

6.0 km/s

6.35* 1

6.6*

78

2468 VELOCITY (KM/SEC)

Figure 11. Traveltime curve and crustal velocity model for southern Nevada Top: Observed (solid dots) and calculated (solid lines)

traveltimes for shot point 3 profile from Yucca Mountain to Death Valley Junction (Figure 5). Definitions: Pg is the "seismic basement" refractor;

is the first intracrustal reflector (24 km); is the second intracrustal reflector (30 km);

PmP is the mantle reflector.

Bottom: Interpreted compressional-wave velocity structure ofthe crust. Velocity boundaries in the upper crust may not have been detected since the minimum source- recorder range was 47 km. Asterisks indicate estimated

24

SHOT POINT 3 EAST PROFILE

Further evidence for the deep crustal structure beneath the study area is provided by the clear secondary arrivals observed on the easternmost profile from shot point 3 (Figure 5). This profile recorded a crust-mantle and two intra-crustal reflections.

In view of the lack of reversal on this profile, the crustal model derived from it was constrained by the other seismic profiles in the area. An average velocity of 3.0 km/s has been used for the near-surface layer, and of 6.0 km/s for the basement (Pg) refractor. The first arrivals along this proifle show considerable scatter (Figure 11), but an average line through these points gives a depth to basement of 1.5 km. The first intracrustal reflection is most clearly observed at a reduced time of 2.6 s and a range of 93 to 97 km (Figure 5). These arrivals can be fit by a pre-criticai reflection from a boundary at 24 km depth where the velocity increases from 6.0 to 6.35 km/s (Figure 11). The second reflection occurs at a reduced time of 3.15 to 3.55 s and a range of 86 to 97 km. These arrivals have been fit by a second pre-critical reflection from a boundary at 30 km depth where the velocity increases from 6.35 to 6.6 km/s. Finally, the mantle reflections between 3.4 and 4.5 s and 81 to 109 km have been fit with a reflection from the crust-mantle boundary at a depth of 35 km. A mantle velocity of 7.8 km/s has been used based on the work of Johnson (1965). This structure is illustrated in the velocity-depth plot of Figure 11.

SUMMARY

Seismic refraction data from nuclear and chemical explosions tiave been used to calculate the crustal velocity structure in the vicinity of Yucca Mountain, southern Nevada. A contour map of P-wave delay times and an unreversed refraction profile have been used in conjunction with gravity models to estimate the configuration of pre-volcanic surface between outcrops at Bare Mountain and Skull Mountain. The models have been constrained by geologic and geophysical information, including geologic mapping, shallow seismic refraction surveys, borehole measurements and the subsurface density distribution as inferred from modeling detailed gravity data. The greatest depth to basement (somewhat more than 3 km) is beneath eastern Crater Flat-western Yucca Mountain, where a graben-iike structure exists in the deeper rocks.

The total crustal thickness has been calculated from an unreversed profile from a nuclear shot at Pahute Mesa. The crust is 35 km thick and contains intracrustal boundaries at 24 and 30 km; an additional boundary at 15 km depth has been identified on the east-west profile across Yucca Mountain.

25

REFERENCES

Christiansen, R. L., Lipman, P. W., Carr, W. J., Byers, F. M., Jr., Orkild, P. P., and Sargent, K. A., 1977, Timber Mountain-Oasis Valley caldera complex of southern Nevada: Geological Society of America Bulletin, v. 88, p. 943-959.

Healey, D.L., Wahl, R.R., and Oliver, H.W., 1980, Complete Bouguer gravity map map of Nevada, Death Valley sheet: Nevada Bureau of Mines and Geology Map 68, scale 1:250,000.

Healy, J.H., Mooney, W.D., Blank, H.R., Gettings, M.E., Kohler, W.M., Lamson, R.J. and Leone, L.E., 1982, Saudi Arabian Seismic Deep-Refraction Profile: Final Project Report: U.S. Geological Survey Open-File Report 02-37, 429 pp.

Johnson, L.R., 1965, Crustal Structure between Lake Mead, Nevada and Mono Lake, California: Journal of Geophysical Research, v. 70, No. 12, p. 2863-2872.

Pancratz, L.W., 1982, Reconnaissance Seismic Refraction Studies at Calico Hills, Wahmonie, and Yucca Mountain, Southwest Nevada Test Site, Nye County, Nevada: U.S. Geological Survey Open-File Report 82-478, 25 pp.

Ponce, D. A., 1981, Preliminary gravity investigations of the Wahmonie Site, Nevada Test Site, Nye County, Nevada: U.S. Geological Survey Open-File Report 81-522, 64 pp.

Snyder, D. B., and Carr, W. J., 1982, Preliminary results of gravity investi gations at Yucca Mountain and vicinity, southern Nye County, Nevada: U.S. Geological Survey Open-File Report 82-701, 36 pp.

Spengler, R. W., Muller, D. C., and Livermore, R. B., 1979, Preliminary report on the geology and geophysics of drill hole UE25A-1, Yucca Mountain, Nevada Test Site: U.S. Geological Survey Open-File Report 79-1244, 43 pp.

26

APPENDIX A

Seismic Recorder Locations

Appendix A is a listing of all recorder sites that were used for this experiment. "Location Number" is the reference number for the site which is used on all maps and record sections. Other information in this appendix is the latitude, longitude, and elevation in feet of each recorder location.

27

SEISMIC RECORDER LOCATIONS

LOCATION NUMBER-

LATITUDE (DEGrMINrSEC)

LONGITUDE (DEGrMINrSEC) ELEV

1234

101102103104105106107108109110111112113114115116117118119120121201202203204205206207208209210211212213214215216217218219220301302303304305

3737373636363636363636363636363636363636363636363636363636363636363636363636363636363636363636363636

146

185348505050484949484848484848484747474746454651515151505050494948484849494949484848484847464545

546

1220215554113047

4241312931150

524434181928265947365

38369

216

5147553

11201254453723283338512

44

4

4

»

»

«

»

»

»

»

»

4

»

»

»

4

37270593323210616319

»54

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

68482510375132425822517709

5 4

61

116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116

250

194700236789

1010111112121313141515151527272626252423232323222221212020181817162323232323

20143219422920405

5045320

387

43205323584656422944265

5524443550594733562656255319546

28134232252422

4

4

4

4

4

4

»

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

66126787220423729689543024910088484696705280202695

62734385696036803210335534603620392541704280430342704200415041104010391038453750365035143500349535004320420041303940375035403432334032973550334033903445351035803578353535753600362033103240318031283070

28


LOCATION NUMBER

LATITUDE (DEGfMINfSEC)

LONGITUDE (DEGrMINrSEC) ELEV

306307308309310400401402403404405406407408409410421422424441442443444445446447448449450466467468469481482483484485486487488489490501502503504505506507

3636363636363636363636363636363636363636363636363636363636363636363636363636363636363636363636363636

4443424147525050505050494948484848494845444443424241414140494848474747474646464646464619202020212122

13*824.136.047*458.40.4

55*556*856*336*29*8

43*519*859.931*130*357*76*3

59*529*446*98*8

24.258.428*057*625*28*9

17*241*952*615.044*418*313*25*4

57*546*332*831*626*321*315*835*33*2

29*856*022.148*915.8

116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116

2323232323270123344556778

21212122222223232324151616171516171718181919202125252525252525

19*223*034*447*033*229*029*717.717*910*442*64*3

30*00*7

33*35.27*2

30*419.314*537*257*423*836*554*111*729.439*47*1

24*510*135*419*556*830.74*5

49*416*450*226*057.829.81*6

18*919*319.119*318*518*718*4

30102950289028403270434033403400346035603620368037403800386039204080412042103150306030202960293028902860282028102750382036903590350035143480342233903340329032553210321031532200220022002200220022002200

29


LOCATION NUMBER-

LATITUDE <DEG>MIN>SEC)

LONGITUDE <DEG,MIN,SEC) ELEV

508509510511512513514515516517518519520521522523524525526527528529530541542543544545546547548549550551552553554555556557558559560561562563564565566567

3636363636363636363636363636363636363636363636363636363636363636363636363636363636363636363636363636

2223232424252526262727272853535252515151505050444545455346464753484852494951495051515235353636373738

428

340

26204511374

285623218

51175440124237255213284736275432127

36136

262558286

43403056224914405

,2 6»9»9,6»1»8.8.7»1»4»4»2»8*7»4.8*4»8.8»8»0*3»0»2.4»2»9« 2*5»7»6.9»9»2.3»6»1.0»4.9»4»2»6»6.7.3»2# 2»5

116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116

2525252525252525252525252527272726262625252524383837373436363634363634353534353434343442424242424242

1818181817161615151514151446174

483110585473

261333124

564634122313273920422

534939*?*?

53474541363329

* jC.

»1»1,1.0.5»0*9.4»1»8.1»8.9»4»1»8.8» 2»9 6»9*8»8.4»1»4»5.0.9*5.1» 2.8» 2»5.1.3*4»7*9.1»2*3*2»4»4»4»1.8

22002200220022002200220022002200220022002200220022005160494048004500429039203810379036203470278028402951292136403800297030203533307937203420313031953500358032603300335734703260300029602780270026802660

30


LOCATION NUMBER

LATITUDE (DEGfMINfSEC)

LONGITUDE (DEGfMINfSEC) ELEV

568569570571572573574575576577578581582583584585586587588589590591592593594595596597598599600619620621622623624625629630631632633634635636637638639640

3636363636363636363636363636363636363636363636363636363636363636363636363636363636363636363636363636

3838394040414242434344403939383837373636353534343332323131303049505052545352484748484849495050504948

32* 156.235.10.46.29.2.

36.11.38.4.

14*42.11.38.6.

36.4.

34.4.

33.2.

31.1.

30.59.28.58.27.56.25.32.14.16.0.

23.36.51.14.58.17.31.55.29.

792053669466697973089306424013439724435915

58.23.9.

16.36.49.

16310

116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116116

4242424141414040403939242424242424242424242424242424252525252543

2423222223242525262626272727282827

25222

47331457401947167

13121339

152025313642475358147

101312364241315835294

581937462

153651

46

.3

.5

.3

.2

.3

.9

.8

.1

.2

.7

.2

.1

.2

.7

.2

.9

.2

.0

.5

.8

.1

.9

.1

.4

.2

.2

.2

.6

.6

.6

.2

.7

.8

.1

.5

.2

.8

.2

.5

.3

.5

.8

.2

.9

.4

.5

.7

.7

.4

.7

26202610259026102620262826402650266026702680275027202690266026302610258025602540252024902470245024202400238023602340231023003700360035803640380037503720330034003560368037803960420043604620495148404680

31


LOCATION NUMBER

LATITUDE <DEG»MIN>SEC>

642643644646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678681682683686687688694

36363636363636363636363636363636363636363636363636363636363636363636363636363636363636

53 19*353 4*653 4*253 34*253 39*753 44*753 44*953 29*253 17*553 17.353 24*153 7*652 44*052 19,952 5*052 4.252 2*252 3*450 56*150 26*549 53*348 37.048 27.248 15.948 5*847 55*747 44*847 33*148 6*648 15*248 15.248 29.248 38.549 0.249 19,549 50.847 25.747 54.148 31.748 51.348 57.449 3.648 38.8

LONGITUDE (DEGfMINfSEC) ELEV

116 46 52.0116 46 13.2116 45 38.5116 44 26.5116 43 55.0116 43 23.1116 42 51,6116 42 25,9116 41 54,1116 41 21,6116 40 44,3116 40 28,3116 40 13.6116 39 54.2116 39 31*6116 39 2*6116 38 35*2116 37 57*4116 37 56*5116 37 29*9116 36 51*2116 36 15*5116 35 41*1116 35 10*6116 34 40*2116 34 12*6116 33 40*6116 33 12*6116 32 39*6116 32 6*8116 31 30*9116 30 56*1116 30 17*3116 29 46*0116 29 11*4116 29 2*7116 15 25*9116 16 6*1116 16 54*8116 18 38*4116 19 10*1116 19 41.6116 23 8*2

3380340033203400352036803808400042004310453346804966472044004320416040403780362034603195318031703170314031603160326033403440352036003720382041003565356036103550355035603320

32

APPENDIX B

Master Shot List and Team-Shot Data Sheets with Tape Grade Scale

The "Master Shot List" (page 33) is a table containing all important information pertaining to each recorded shot or nuclear event. Most of the information is self-explanatory. "Shot Point" refers to the location number for that particular shot. For this experiment, the shot point and shot number are the same. Additional information and the size of the shot are listed to the right of the data.

The "Team-Shot Data Sheets" (pages 34-43) contain all of the information related to the seismic recorders. Each set of 20 recorders is given a designated team number under which data is stored and referenced. Each "Data for One Team-Shot" contains shot number, team number, shot point, and shot time. Column headings for the table are explained below:

Loc - location number from the seismic recorder location file (Appendix A)

Dist (km) - distance in kilometers from the shot point to the recorder location

Azim - azimuthal projection from the shot point to the recorder location

Unit - I.D. number of the recording unit

Chron - chronometer correction for the recorder at shot time (calculated from the total clock drift)

Chan - channel number (1, 2, or 3) which was selected to be digitized by the computer

Cl, C2, C3 - amplifier gain setting (db) for each data recording channel

Tape Grade - value used to rate the performance quality of the seismic recorder (see Tape Grade Scale, following)

Additional information relevant to analysis of the data is listed to the right of the data columns.

The "Tape Grade Scale" (page 44) is a listing of all tape grade numbers used on the Team-Shot Data Sheets. Each number corresponds to a specific problem with the recording unit.

MASTER SHOT LIST

EXPERIMENT NO,

12

NEVADA TEST SITE* 1980-1982

SHOT

NUMBER

1 2 3 4

DATE

APR 26* 1980

MAY 29* 1981

JUN

6* 1981

APR 28 *

1982

SHOT

POINT

LATITUDE

1 37 14,9057

2 37

6.1111

3 37 18.2038

4 36 53.3450

LONGITUDE

116 25.3440

116

0.2438

116 19.5358

116 47.3204

SHOT TIME

117 17

149 16

157 18

119

4

0 0 0 0

0.083

0.094

0.084

0.014

COLWICK -

APPROX. 120 KT.

ALIGOTE -

APPROX. 20 KT.

HARZER -

APPROX. 120 KT.

BEATTY -

2480 LBS.

OJ

DATA FOR ONE TEAM-SHOT

EXPERIMENT NO* 12 NEVADA TEST SITE* 1980-1982 SHOT NUMBER 1 TEAM 1 SHOT POINT 1SHOT TIME: 117:17; o: o*083

TAPE LOG DIST(KM) AZIM UNIT CHRON CHAN Cl C2 C3 GRADE

34

123456789

10111213

120121118220219218217216215114115116117

56*54*52*50*49*49*49*48*47*53*53*52*52*

368532912865985547024117753072054982924

165*0164*9164*7164*6166*5167*5168*8171*1172*0159*6160*5161*5162*8

103322638

12513060909415172425

0-4 O

03

-5 »522 *?-5

333333

33

3

44444444444444444444444444

26262626262626262626262626

62626262626262626262626262

000

O/ 6/30O/ 6

0100

6/17/2410

18


EXPERIMENT NO* 12 NEVADA TEST SITE* 1980-1982 SHOT NUMBER 1 TEAM 2 SHOT POINT 1SHOT TIME: 117:17: o: o*083


123456789

101112

211210301310302303304305306307308309

48*48*48*49*50*52*53*55*56*58*59*61*

433260962884640354799325817342809294

175*8176*9177*1176*9177*0176*9177*0177*0177*0177*1177*5177*8

62976311811033525112410410530

010

-3-40

-80

-7041

33333333333

444444444444444444444444

262626262626262626262626

626262626262626262626262

17/18/25000000000

O/ 6/300

DATA FOR ONE TEAh-SHOT

EXPERIMENT NO* 12 NEVADA TEST SITE* 1980-1982 SHOT NUMBER 1 TEAM 3 SHOT POINT 1SHOT TIME: 117:17: o: o*083

35

123456789

10111213

LOG DIST(KM) AZIM

101102103104105106107108109110111112113

61*214 57*642 55.961 55*876 56*613 54*382 53*664 53*834 53*569 53*460 53*208 52.822 52*917

143*4 140*3 142*5 144*9 149*7 151*5 152.7 154*2 154.9 155*9 156*7 157*5 158*6

181

434076759889

113112143133101

IRON

0033

-4201

-22

241

-2

CHAN

33

3333

33

Cl

44444444444444444444444444

C2

26262626262626262626262626

C3

62626262626262626262626262

TAPEGRADE

00

17/25110

O/ 6/110011

O/ 6/300

DATA FOR ONE TEAh-SHOT

EXPERIMENT NO* 12 NEVADA TEST SITE* 1980-1982 SHOT NUMBER 1 TEAM 4 SHOT POINT 1SHOT TIME: 117:17: o: 0.093


1^

3456789

101112

214213212209208207206205204203202201

474848474745444444434242

.904*073*254*777*308*826*947*887*090*166*831.503

173*0174*0174*9177.2177*6177*2178*6180.7182.0183*1183*5184*2

141939

1215356666970727793

0-41151*?

20210

3333333

3333

444444444444444444444444

262626262626262626262626

626262626262626262626262

0000000

12/17000

0/12


EXPERIMENT NO* 12 SHOT NUMBER 2 SHOT POINT 2SHOT TIME: 149:16: o: 0*094

NEVADA TEST SITE* 1980-1982 TEAM 1

LOG DIST(KM) AZIM UNIT CHRON CHAN Cl C2 C3TAPE

GRADE

36

123456789

10

401402403404405406407408409410

28*09028*07128*09029*01029,94130,83431*67432*43133*48033*699

180181183188189190191192193194

*8»3»2*6»9*6*5*6*6»9

15172425263236384458

11o«u

-5726 3

12 *?27

-37 6

3111111111

64646464646464646464

42424242424242424242

82828282828282828282

0000000000





GRADE

12345678910

421422106424107108109110111112

33*33*33*33,33*35*35*36*36*36*

319249473856863030337016371728

197*8198*9199*7200*7201,9203,2204,2205*4206.4207*6

10133034495152556263

460

109 -6

-221279

1111

111

64646464646464646464

46464646464646464646

82828282828282828282

0000130003





37

123456789

10

450449448447446445444443442441

59575756555453515049

*494*804*254«193*182*172*354*867*636*262

216*6217*0217*1217*4217*6217*8218*1218*4218*8219*3

1182235404365747576

390

14-401415 33017

-13

121111

111

64646464646464646464

46464646464646464646

82828282828282828282

000000

25000


iEXPERIMENT NO* 12 NEVADA TEST SITE, 1980-1982SHOT NUMBER- SHOT POINT SHOT TIME:

2 TEAM 4 2149:16: o: 0*094


GRADE

123456789

113114115116117466467468469

37*38*38*39*40*37*39*40*42*

588394982616506790684989397

208*6209*3210*1211*0212*2216*6216*6216*3216*7

141939485356666970

-8-35

54204

-331011

111111111

646464646464646464

464646464646464646

828282828282828282

000000000


EXPERIMENT NO* 12 NEVADA TEST SITE* 1980-1982 SHOT NUMBER 2 TEAM 5 SHOT POINT 2SHOT TIME: 149:16: o: 0*094


123456789

10

481482483484485486487488489490

41*42*43*44*44*45*46*46*47*47*

873475152001676513085702323955

213*8214*7215*4216*4216*8217*3218*2218*8219*5220*1

3122328314573788283

1229334315 18

-25_sr

\J

22

1111

1111

64646464646464646464

46464646464646464646

82828282828282828282

12000010000

38


EXPERIMENT NO* 12 NEVADA TEST SITE* 1980-1982 SHOT NUMBER 3 TEAM 1 SHOT POINT 3SHOT TIME: 157:18: o: o»084


GRADE

1o3456789

1011121314151617181920

501502503504505506507508509510511512513514515516517518519520

108108107106105104104103102101100999897969595949392

*960*102*284.479*672»849*018»207*395»584»785»990*344»550»752»952*141*392.531»707

184*5184*6184*6184*6184*7184*7184*7184.8184*8184*8184*9184*9185.0185*0185*1185*1185*1185*2185*2185*3

151724252632363844586071859094103106125130146

14 9

-8315_o

-22-15

i.;~ 36

-148-23-13-76

121278

40-4365

-55-27

33

333

3

3

3333333

4444444444444444444444444444444444444444

2626262626262626262626262626262626262626

6262626262626262626262626262626262626262

00

17170003010110000000


EXPERIMENT NO. 12 SHOT NUMBER 3 SHOT POINT 3SHOT TIME: 157:18: o: o*084



GRADE

123456789

1011121314151617181920

521522523524525526527528529206530207209301302303304444446448

47*47*48*49*49*50*50*51.51*51*51.52.54*55*56*58.60*64*66*68*

543752192117730034828716695582822265191347979662099507286288

194*9193.9193.4192.7192*0191.3190*8190.5189*2188.4187*4187.0186*7186*4186*0185*6185.5183.8184*3184.9

101330344951525562636497104105110118124137142145

42-26

810

-49-8216141716266

19-108-32-44-7549 2

3333

33

3

3

3331

6464646464646464646464646464646464646464

4646464646464646464646464646464646464646

8282828282828282828282828282828282828282

00003003330

1717030000

17

39

EXPERIMENT NO* 12 SHOT NUMBER 3 SHOT POINT 3 SHOT TIME: 157:10:


NEVADA TEST SITE, 1980-1982 TEAM 3

0: 0*084


GRADE

123456789

1011121314151617181920

541542543544545546547548549550551552553554555556557558559560

67*67.66*65*50*64.63.62*51*60*60*52*58*58*54*57*56*54.53*52.

739007171433322142279080081973062900888121404058116993858093

204.5204*4203*8203.6205.3203*7203*8204*0205*2204*2204*3204*7203*9203*8204*4203*8203*9204*3204.6205*0

118223540436574757679878998

100101112113133143

373215 855

2261251

16-228885837

-48-1619

-59

333

3

3

3333

3

33

6464646464646464646464646464646464646464

4646464646464646464646464646464646464646

8282828282828282828282828282828282828282

0001

1717290

170

170000170

1700


EXPERIhENT NO. 12 SHOT NUMBER 3 SHOT POINT 3SHOT TIME: i57:ie: o: o*084


123456789

1011121314151617181920

LOG

561562563564565566567568569570571572573574575

576577578

DIST(KM)

86*85*84*84*83*82*81*80*80*78*77*76*75*74*72*

71*70*69,

347552795004250486739946240831688557169055924

719634568

AZIM

203,7203*8204*0204*2204*3204*5204*7204*8205*0205,1205*2205*3205,4205,4205,5

205*5205*2204*9

UNIT

14193948535666697072779396115119121122132134139

CHRON

-556978

-13 o

3192

-11-35

1-19 131319

CHAN Cl

1

113

3

13

3333

333

6464646464645864646464646464646464646464

C2

5246464646464646464646464646464646464646

C3

8282828282828282828282828282828282828282

TAPEGRADE

0100030

170030000

20200

0/170/30

40


EXPERIMENT NO* 12 NEVADA TEST SITE* 1980-1982SHOT NUMBER 3 TEAM 5SHOT POINT 3SHOT TIMEJ 157tl8: 0: 0*084


GRADE

123456789

1011121314151617181920

581582583584585586587588589590591592593594595596597598599600

70*71*72*73*74*75*76*77*78*79*80*81*82*83*84*85*86*87*87*88*

545535485499451390379318264236330293247220167134071026999952

185*5185*6185,5185*4185*2185*2185*3185*3185*3185*4185*4185*4185*5185,5185*5185*5185*5185*5185*5185*5

3122328314573788283889299107108120128129131136

1339

-1855311147

-23-19273820

-78-165

447

294135

-133

111

1

1

1

1

6464646464646464646464646464646464646464

4646464646464646464646464646464646464646

8282828282828282828282828282828282828282

33

17000

1717171717030

1731030


EXPERIMENT NO. 12 SHOT NUMBER 4 SHOT POINT 4SHOT TIME: 119: 4: o: 0*014



GRADE

123456789

1011121314151617181920

409410421422106424107108109110111112113114115116117408619620

62.61.60.59.59.58.57.56*56.55.54.53.52.52.51.50.49.63.64.65.

722945301697218526862812137254543667831124439631545400459211

98.298.397.797.597.797.997.898*798*899*399*599*6100*3100.9101*4101*8102*497.396*395*1

151724252632363844586071859094103106125130146

119

-10-12

22

_ O «£

2-2 *~t 309942

4 7

7 A

1

121

122221222

1

2

2424242424242424242424242424242424242424

66666666666666666666

4242424242424242424242424242424242424242

01

120001000000000

250

120

41


EXPERIMENT NO. 12 SHOT NUMBER 4 SHOT POINT 4SHOT TIME: 119: 4: o: 0.014

NEVADA TEST SITE, 1980-1982 TEAM 2

123456789

1011121314151617181920

LOG

640639638637636635634633632631630629625624623622621528204201

DIST(KM)

30.23329.50629.13229.88030.43430.78231.34931.84032.44833.07934.53635.22535.27536.16436.89435.19734.09432.19031.36929.647

AZIM

106.1103.6101.2101.4101.5101.7103.1104.9105.9106.4106.7105.591.589.287.094.099.698.797.794.9

UNIT

101330344951525562636497104105110118124137142145

CHRON

18-422262222333680

»5

0-13

6

CHAN Cl

21111111

11112111111

5424242424242424242424242424242424242424

C2

186666666666666666666

C3

2442424242424242424242424242424242424242

TAPEGRADE

00000000130

0/17/3000

0/17/30000000

VABM

UE25A-1


EXPERIMENT NO. 12 NEVADA TEST SITE* 1980-1982SHOT NUMBER 4 TEAM 3SHOT POINT 4SHOT TIME** 119: 4t 0! 0*014

LOG DIST(KM) AZIM UNIT CHRON CHAN Cl C2 C3

42

TAPE GRADE

123456789

1011121314151617181920

4642643644645646647648649650651652653654655656657658659660

0012

45567889

10101111121314

.000

.676

.708

.544

.296

.089

.894

.669

.269

.051

.855

.779

.183

.601

.180

.813

.524

.201

.116

180*093.7106*8101.5

84.483*482*883*687*990*790*789*492*396*199*6101*4100*9100*699*7

118223540436574757679878998100101112113133143

19

-32

-182

8

11-18 5

99

-19

515

-10 vJ

116

331

113333331131331

6464644444442424242424242424242424242424

46464626262666666666666666

8282826262624242424242424242424242424242

10001000000000000000

BAD LOG


EXPERIMENT NO* 12 SHOT NUMBER 4 SHOT POINT 4 SHOT TIME: 119: 4:

NEVADA TEST SITE* TEAM 4

o: 0*014

1980-1982

123456789

1011121314151617181920

LOG

661662663664665666667668669670671672673674675676677678

DIST(KM)

141516181920212122232324252526272727

.634*555*819*626*520*351*164*914*772*556*847*491*312*962*770*300*955*924

AZIM

107*7110*2112*3118*0117*6117*5117*3117*2117*0117*1114*0112*6111*8110*3109*0107*1105*4103*4

UNIT

14193948535666697072779396115119132134139

CHRON

20145810

-1046707

-223

-96

145

CHAN Cl

33

11111111331

1

242424242424242424242424242424242424

C2

666666666666666666

C3

424242424242424242424242424242424242

TAPEGRADE

00

250000

0/3000

0/300/11

00

25250

25

TRUNCATED


EXPERIMENT NO, 12 NEVADA TEST SITE* 1980-1982 SHOT NUMBER 4 TEAM 5 SHOT POINT 4SHOT TIME: 119: 4: o: 0,014


43

123456789

1011121314151617181920

118681682468683219218686687688216215214213212694301209530206

47,48,47,46,46,

969654490644069

45,22544,43,42,41,40,39.39,38,37,36.36,35.34,34,

238434625823851989243545866985252836984148

103,5103,0102,2101,7101,2101,1101,1101,0101.0100.9100,8100,7101.3101,9102,5103,6104,4102,698,998,5

3122328314573788283889299107108120128129131136

21

_.«=: %j5300

12_oJi.

5633

-18411121

12121111

11211111111

242424242424242424242424r> *

24242424242424

66666666666666666666

4242424242424242424242424242424242424242

00000000100000000000

44

Tape Grade Scale

0 - Good

1 - Tape did not run

2 - Tape ran but no signal

3 - Skipped record time

4 - Fast forward; no signal

5 - Rewound and erased

6 - Weak signal; cannot read TCT; low record level

7 - Continuous calibration of periodic offsets

8 - Noise, sinusoidal

9 - Noise, spike

10 - Noise, WWVB cross-feed

11 - Noise, periodic ticks

12 - Noise, random

13 - Bad clock

14 - Off frequency, tape speed

15 - Calibration

16 - Incomplete record; recorder stopped

17 - Bad time code

18 - Tape speed way off; belt slipped

19 - Turned on too early

20 - In for repair; not deployed

21 - Geophone disconnected or shorted

22 - Wrong unit number

23 - Wrong gain settings

24 - Late start

25 - Bad geophone test (usually no signal)

26 - One or more channels missing

27 - Bad WWVB

28 - Unit or tape damaged/vandalized

29 - Wrong program time

30 - Digitized without calibrations

31 - Amplifier out of balance

45

APPENDIX C

First Arrival Times

Appendix C is a listing of the first arrival times picked from the record sections. Included are: shot point number, recorder site location, traveltime picks in both real and reduced (T-X/6) times, and distance (km) and azimuth of the recorder from the shot point.

46

SHOT POINT

111111111111111111111111111111111111111

2222222222

RECORDER LOCATION

301310302303304305306307309308120121118219218216215116220210101102106107108109113112214213212208209207206204202201203

482483484485487488489490421422

TRAVEL TIME (REAL)

9*1859.3199*4709*7269*90610*11610*33510*58411*15110*93810.1959*9949*7299*3569*3139*1559*1049*7009*4939*13310*75710*1229*5099*4249*4179*3689*5959*4099*1099*1879*1078*9059*0088.7388*5668.5138.3848.3948.424

7.2997.4977.5747*6817.7817.9498.1328.4575.7635.772

TRAVEL TIME (T-X/6)

1.0251.0051.0301.0000.9400.8950.8650.8600.9350.9700.8000.9050.9101.0251.0551.1351.1450.8701.0151.0890.5550.5150.4450.4800.4450.4400.7750.6051.1251.1751*0651.0201.0451.1001.0751.1651.2451.3101.230

0.2200.3050.2400.2350.1000.1650*2450*4650*2100*230

DISTANCE

48*96249*88450*64052*35453*79955*32556.81758.34261.29459.80956.36854.53252.91249.98549.54748.11747.75352.98250.86548.26061.21457.64254.38253.66453.83453.56952.91752.82247.90448.07348.25447*30847.77745.82644.94744.09042.83142.50343*166

42*47543*15244*00144*67646.08546*70247.32347.95533.31933.249

AZIMUTH

177.147176.949176.965176.886176.950176.974176.970177.142177.834177.481164*959164.851164.717166.485167.501171.100172.036161.454164.573176.852143.358140.286151.485152.705154*191154.868158.640157.511173.038173.978174.894177.566177.245177.224178*586182*035183.483184*193183*099

214.655215.387216.383216.812218.189218.824219.453220.051197.839198.918

47

SHOTPOINT

22222222292299

99

292 99 9 9 9

22222229

2

3333333333333333

RECORDERLOCATION

106424109110111401402403404405406407408409410448447446113114115116117466467468469441442443445449450

522561521524523526527530301303304446444563564565

TRAVELTIME(REAL)

5*7645*8786*0746*1886*3025*1825*0385*1125*3255*4605*5795*6695*5755*8755*82710*38710*24510*0826*6806*8097*0526*9437*1116*7086*9897*1217*2969*0289*2869*3849*96810*48810*798

9*36415*3419*2899*5119*4329*5099*5819*74710*19410*70710*93611*82811*52615*08214*95114*825

TRAVELTIME(T-X/6)

0*1850*2350*1850*1850*2400*5000*3600*4300*4900*4700*4400*3900*1700*2950*2100*8450*8800*8850*4150*4100*5550*3400*3600*4100*3750*2900*2300*8180*8460*7390*9390*8540*882

1*4050*9501*3651*3251*4001*1701*1101*1100*9700*9300*9200*7800*7750.9500*9500*950

DISTANCE AZIMUTH

33*473 33*856 35*337 36*016 36*371 28*090 28*071 28*090 29*010 29*941 30*834 31*674 32*431 33*480 33*699 57*254 56*193 55*182 37*588 38*394 38*982 39*616 40*506 37*790 39*684 40*989 42*397 49*262 50*636 51*867 54*172 57*804 59*494

47*752 86*347 47*543 49*117 48*192 50*034 50*828 51*822 55*347 58*662 60*099 66*286 64*507 84*795 84*004 83*250

199*678 200*740 204*202 205*369 206*374 180*758 183*185 186*199 188*617 189*893 190*618 191*504 192*604 193*621 194*913 217*095 217*354 217*582 208*557 209*280 210*057 210*985 212*182 216*554 216*559 216*299 216*735 219*266 218*822 218*441 217*820 216*995 216*601

193*922 203*703 194*893 192*684 193*392 191*334 190*834 187*441 186*406 185*645 185*492 184*320 183*773 204*018 204*183 204*320

48

SHOT POINT

3333333333333333333333333333333333333333333

444444

RECORDER LOCATION

567569570572573574575576577578542541543548550553554557555559560552505506507509515517518520584585586592598600519516514511502501594

642643644646647648

TRAVEL TIME (REAL)

14*55314.25814*11813*80513*65313*52313*28913.09312.88212*64512*20312*34512.05911*54211*38711*09511*00710.72310.50710.42110.10710.24718.74718.39018.09117.98617.28516.83716.56716.29113.11513.35813.43014.36715.35115*74316.46416.79617.04817.58018.98519.05614.645

0.2950.4240.5280.8701.0451.207

TRAVEL TIME (T-X/6)

0.9300.8850.9801.0451.1251.1801.1351.1401.1101.0501.0351.0551.0301.1951.2251.2801.3201.3701.4401.4451.4251.4301.1350.9150.7550.9201.1600.9800.8350.8400.8650.9500.8650.8180.8460.9180.8750.8040.7890.7820.9680.8960.775

0.1820.1390.1040.1540.1960.225

DISTANCE

81.73980,24078.83176.55775.16974.05572.92471.71970.63469.56867.00767.73966.17162.08060.97358.88858.12156.11654.40453.85852.09352.900105.672104.849104.018102.39596.75295.14194.39292.70773.49974.45175.39081.29387.02688.95293.53195.95297.550100.785108.102108.96083.220

0.6761.7082.5444.2965.0895.894

AZIMUTH

204.672205.018205.062205.263205.376205.420205,461205.460205.177204.881204.432204.458203.813204.014204.187204.187204.187203.934204.409204.578204.958204.702184.668184.708184.741184.812185.059185.132185.169185.262185.428185.181185.216185.425185.486185.457185.220185.094185.018184.888184.575184.533185.490

93.697106.839101.49784.43083.39982.779

49

SHOT POINT

44444444444444444444444444444444444444444444444444

RECORDER LOCATION

649650651652653654655656657658659660661662664665666667668669670671672673674677638639201637640636635633528631630530209212213214215204634621206622629625

TRAVEL TIME (REAL)

1*3581*4861*6311*7791*9552*0152*0852*2032*2222*4552*5252*6562*7712*9893*6083*8004*0024*2094*4994*5424*6444*7284*9425*1295*2095*4995*8165*8435*8665*9055,9075*9475*9635*9966*1546*1106*3246*4346*7196*9076*9637*0807*2406*1396*1356*2936*3526*5416*5036*504

TRAVEL TIME (T-X/6)

0*2460*2750*2890*3040*3250*3180*3180*3390*2540*3680*3250*3040*3320*3960*5040*5460*6110*6820*8460*7460*7180*7540*8610*9110*8820*8390*9610*9250*9250*9250*8680*8750*8320*6890*7890*5960*5680*6040*7460*5960*5390*5390*5750*9110*9110*6110*6610*6750*6320*625

DISTANCE

6*6697*2698,0518*8559*77910*18310*60111*18011*81312,52413*20114*11614*63415*55518*62619*52020*35121*16421*91422.77223*55623*84724*49125*31225*96227*95529*13229*50629*64729*88030*23330*43430*78231*84032*19033*07934*53634*98435*83637*86638*54539*24339*98931*36931*34934*09434*14835*19735*22535*275

AZIMUTH

83*57187*94490*70590*67989*38592*28096*12599*645101*401100*858100*56099*720107*739110*200118*008117*610117*492117*298117*203117*045117*055113*955112*617111*845110*251105*422101*249103*56994*859

101*372106*081101*544101*702104*90098*696106*412106*72598*891102*642102*481101*871101*275100*68597*663103*14099*59598*51394*007105*54991*466

50

SHOT POINT

44444444444444444444444444444

RECORDER LOCATION

624301623694116115114113112111110109108424106422409408620216688686218219683468682118681

TRAVEL TIME (REAL)

6*5956.6816.8456.7548*9789*0779*1849.2529*3629*4449*5559*74510*25810*10810.09510.41711*02911*02711*5227*4127*5957*8217*9348*0988*4998*5738*6638*7268*797

TRAVEL TIME (T-X/6)

0*5680.6390.6960*5890*5390*5040*4960*4460*4180*3540*3460*3890*7890.3540*2250*4680*5750*4610*6540*6040*6250*5820.5610*5610*8210*7990*7480*7310*688

DISTANCE

36*16436.25236*89436*98550*63151*43952*12452.83153*66754.54355*25456*13756*81258*52659.21859*69762*72263*40065*21140*85141*82343*43444*23845*22546*06946*64447*49047*96948*654

AZIMUTH

89*244104*41286.984103*591101*797101.356100*923100*25399*57499*47099*30298*83298*69297*90697*67297*54898*18297*28495.052100*807100*924101*023101*070101*120101*151101*655102*238103*456102*996

GPO 787-042/117

united states department of the interior lynn r. … · figure 1. recorder and shot locations for...

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