GEOLOGIC MAP OF THE NOR AREVIK COAL SITE ... - USGS

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1505.5. 1488.7. 1541.2. DH - 3. DH - 1. DH - 4. DH -8. DH - 2. A '. A. 0 m. 0 m. 500 m. DH - 7. DH - 6. DH - 5. 27. 26. 23. 16. 28. Scale 1:1,000. Contour interval 5 ...
U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY

MISCELLANEOUS FIELD STUDIES MAP MF–2380 Version 1.0 Pamphlet accompanies map CORRELATION OF MAP UNITS 25

1550 15

Qc

Qc

Holocene

QUATERNARY

1525 Unconformity

15

Tnac

T - 15

00

Neogene

5

152

Tnas Tnacb

Tnas

Unconformity

S-2 400 m 14

00

Qc

T-4

15

28

Tnacb

Paleogene

75

Ti

T - 11

TERTIARY

DESCRIPTION OF MAP UNITS

1505.5 Qc

1500

DH - 5

Nor Arevik Deposit (Neogene)—A terrestrial deposit divisible into three distinct units: in ascending order, coal bearing, sandstone, and conglomerate. The upper two units are commonly missing. Deposit covers only 2.75 km2 at the Nor Arevik coal site. Considered Miocene, or early or middle Pliocene in age by previous workers; generalized in our report as Neogene. As thick as 475 m

S-3 T-5 T - 13

Tnac

Conglomerate unit—Clast-supported conglomerate containing subangular to subrounded, pebbles to boulders of various intrusive igneous rocks. Weathers light brown to bluish gray. Includes some lenticular interbeds of medium-grained to very coarse grained sandstone. Erosional contact with underlying unit. As thick as 400 m

Tnas

Sandstone unit—Poorly sorted, very fine to very coarse grained sandstone consisting of subangular to subrounded grains of quartz and lithic fragments. Weathers light brown. Includes some lenticular bodies of matrix-supported conglomerate similar in composition to the overlying conglomerate unit. Conformable contact with underlying unit. Unit ranges from 5 to 48 m thick

0

150

1525

A

Myulk Creek

Tnac

Holocene deposits—Gravel, sand, silt, and clay. As thick as 30 m

5

300 m

147

DH -8 DH - 6 S -1 T-2

Tnacb Tnas

DH - 2

Tnacb

Ti

1541.2

Coal-bearing unit—Mostly mudstone, combustible shale, and coal. Mudstone is carbonaceous and weathers dark gray; ironstone concretions are rare. Combustible shale is fissile and weathers dark brown; bed thickness ranges from 5 cm to 3.3 m and fossil plant debris are common. Coal is subbituminous and occurs in two zones in upper one-third of unit; coal bed thickness ranges from 2 cm to 1.6 m. Very thin to thin beds of siltstone are common throughout unit, and very thin beds of very fine grained sandstone are rare in lower part of unit. Light-yellowish-brown-weathering, thin-bedded, argillaceous limestone occurs locally in upper one-third of unit; plant and mollusk fossils are common. A basal conglomerate 19 m thick fills a erosional depression in underlying igneous rock at one location. Ranges from 10 to 25 m thick

T - 10

1488.7

T - 12

DH - 4 200 m

DH - 1

T - 14

26

16

Ti

Intrusive rocks (Paleogene)—Various acidic to basic intrusive igneous rocks; granodiorite predominates

S-5 152 5

T-9

23

5

147

DH - 7

S-4

1500

1500

A'

T-7 T - 16

Contact—Approximately located

23

Strike of bedding—Showing dip direction

50

15

Tnacb

T-6

27

Strike and dip of bedding

100 m

Mine—Includes trenches T - 3 and T - 8

Ti

DH - 3 T-1

DH - 8

147

Drill hole—Drilled by Drobotova and Saponjian, between 1993 and 1996

5

Tnac

T-6

Trench—Cut by Drobotova and Saponjian, between 1993 and 1996

Ti S-3

Tnas

My

ulk

1475

Shaft—Dug by Drobotova and Saponjian, between 1993 and 1996

1450

Cr

eek

0m

Qc Base from Tarayan (1942). Original contour interval 5 m. Based on a Geographic Positioning System (GPS) reading, lat 39°01'20" N. and long 46°12'15" E. lie within the Nor Arevik coal site. Digitized by Gourgen Malkhassian.

400 m

300 m

200 m

100 m

0m

Building

Mapped by Edward A. Johnson, Artur Martirosyan, and Brenda S. Pierce, June 1999. Modified from Tarayan (1942) and Drobotova and Saponjian (1996).

Scale 1:1,000 200 m

100 m

0m

500 m

Stream

Manuscript approved for publication January 22, 2002 1541.2

Contour interval 5 m

A

A

A' METERS 1550

1525

1525

Myulk Creek

A' Line of cross section

METERS 1550

1500

Survey point—Elevation in meters

1500

Tnac 1475

1475

Tnas

Ti 1450

1450

1

Tnacb

GEOLOGIC MAP OF THE NOR AREVIK COAL SITE, SOUTHERN ARMENIA By Edward A. Johnson1, Artur Martirosyan2, Brenda S. Pierce3, Gourgen Malkhassian2, and Michael E. Brownfield1 2002

U.S. Geological Survey, Denver, CO 80225 2 U.S. Geological Survey Armenian Staff, Yerevan, Armenia 3 U.S. Geological Survey, Reston, VA 20192

Any use of trade names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Geological Survey This map was produced on request, directly from digital files, on an electronic plotter For sale by U.S. Geological Survey Information Services Box 25286, Federal Center, Denver, CO 80225 1-888-ASK-USGS This map is also available as a PDF at http://geology.cr.usgs.gov/greenwood-pubs.html