PROFESSIONAL PAPER 1689PLATE 24 OF 26

U.S. DEPARTMENT OF THE INTERIORU.S. GEOLOGICAL SURVEY

Keefer, W.R., Whitney, J.W., and Taylor, E.M., eds., 2004, Quaternary Paleoseismology and Stratigraphy of the Yucca Mountain Area, Nevada: U.S. Geological Survey Professional Paper 1689

U.S. DEPARTMENT OF ENERGYPREPARED IN COOPERATION WITH THE

5 10 15 20 25 30 FEET

1

0

0 2 3 4 5 6 7 8 9 METERS

Horizontal and vertical scale

Modern rootModern burrows

Modern burrowsBenchAvk

TRENCH RV4, WEST WALL

TRENCH RV4, EAST WALL

TRENCH RV4A, WEST WALL

55

4

33

2e

2b

11c 1

1c

TL-54

Location of soil-horizon andlithologic-unit descriptions

1

2e

3

3 3b4 4

5

5 5 54

43

3

3

2e

Modern burrow

Spoil

5

Coppice mound

4

3

2c 2c

2a

2b2f

2c

2b2a 2b

2a

4Bkb2

3Bkb1

2Bkb1

2Kb1

2Kqmb12Bwb1B

Avk

2c2f

2e

2a1

2e

3a

3

33a

3

3

34

55

2b 2b

2a2b 2a 2b

2a

2a

1

2f

3 3b

3b3c

3

34

55

2c2e

2c2b

3

2b

1a1c 1b

2c2c 2c

2b 2b 2b2c

1 1

2d

2c

2e

1

2f

2f

2d

2c 2c

2c2b

1

2e

2b

2c

2e

2f 2f

1

3c

5

54

33

3

2e

43

3

3

55

3b3b

3b3

34

3b

33c

3b

444 4

43c 3

5 5(B)

5(B)

5(B)

5

Brown laminarsilty sand

Weak AvLoose brownsilty sand

Loose brownsilty sand

5(Avk)

5(Avk)

5(Avk)5(Avk)5(Avk) 5(Avk)

5(Avk)

5(Avk)5(Avk)5(Avk)

5(Avk)

5(Avk)

5(Avk)(Avk)

(Bwb1)

3

5(B)5

43

3

(Bwb1)

(2Kqmb1)

(2Kb1)

(3Bkb1)

(2Bkb1)

(4Bkb2)

(Bwb1)(2Kqmb1)

(2Bkb1)(2Kb1)

(Bwb1)(2Kqmb1)

(2Bkb1)

55

43

3

33a

2

5

43

3

3

5 (2Kqmb1)

3 3 33

Loose, reworked, brown silty sand

4

3

44

4

3

4

(2Kqmb1) 3 33

3 44 4 4 4

45 5

5 5

55

5 (Avk)

5

Loose, reworked, brown silty sand

4

3

5 5

3

3

3

3

Brown silty sandBrown

silty sand

543

3

43

3

5

43

3

3

3

34

Approximate base of secondary carbonate(CaCO3 stage II+ morphology)

Fault zone, reworked by burrowing animals

(2Kqmb1)

Approximate base of secondary carbonate(CaCO3 stage II+ morphology)

Approximate base of secondary carbonate(CaCO3 stage II+ morphology)

Approximate base of secondary carbonate(CaCO3 stage II+ morphology)

Approximate base of secondary carbonate(CaCO3 stage II+ morphology)

Approximate base ofsecondary carbonate(CaCO3 stage II+ morphology)

Approximate base ofsecondary carbonate(CaCO3 stage II+ morphology)

Silty sandBrown silty sand

33

3

445

5

5

3

2e

2d

11d

3

3

3

5(B)

Silty sand

4

2f

2f2f2e

? ??

?

1d1d

1 1 1 11b

1

2d

4

3 3 3 3

33d

3b

2e

2d

3

4

Silty sand5(Avk)5(Avk)5(Avk)

5(Avk)5

Brown silty sand

5

2e

3

5 Brown silty sand3

Bench floor

Approximate base of secondary carbonate(CaCO3 stage II+ morphology)

Approximate base ofsecondary carbonate

(CaCO3 stage II+ morphology)

(2Kb1)

(2Bwb1)

(2Kqmb1)3

(2Bkb1)

(3Bkb1) 2e

(4Bkb2)

Brown silty sand5(B)

Coppice moundCoppice mound

33

???

?

54

Brown silty sand (Bwb1)

Brown silty sand Brown silty sand

?

TL-53-

HD 1805

HD 1804

HD 1803

Bench floor

NORTH

NORTHSOUTH

NORTHSOUTH

SOUTH

EXPLANATION

TL-53

3

(2Kqmb1)

Combined lithologic-unit/soil-horizon boundary—Dashed where approximately located, queried where uncertain

Lithologic-unit boundary—Dashed where approximately located, queried where uncertain

Soil-horizon boundary—Within lithologic units, most soil- horizon boundaries correspond to lithologic-unit boundaries. Queried where uncertain

Fault margin—Dashed where approximate, queried where uncertain

Fracture—Dashed where approximate, queried where uncertain

Bedding

Shear zone

Zone of crossbeds

Cavity

Photogrammetric target

Location of sample for age determination—Number refers to sample listed in table 39

Zone of fissile bedding

Selected bedrock clasts

Selected silica/carbonate clasts

Carbonate-silica stringers

Krotovina

Rhizolith

Modern roots

Modern burrows

Lithologic unit—Letters a, b, and so on designate subunits

Soil horizon

PLATE 24. LOGS OF TRENCHES RV4 AND RV4A