Britomartis

Chasma

Artemis

E

E

E’

E’

B C B’ C’

High

Low

TR

Da

TC

D

Q

J

AP

AP

A

B

fz

LP

ZP

C

C’

B’

B

cfl cu cp fcCBM s cf fu rf

fchQ fsAa fsAb fsAc

fcAa fcAb

fl1b

frZ

tAa tAb

flu

fu

tAa

tAa

fu

fu

fchQ

fI1b

fcAa

fcAa

fu

fu

fu

fI1b

fI1b

s

s

s

s

s

s

s

s

s

s

s

flu

flu

flu

flu

tAa

flu

flu

flu

flu

tAa

tAa

fu

fu

fsAa

fsAa

cu

cfl

cp

cu

cfl

flu

flu

flu

flu

flu

tAb

tAb

tAa

flu

flu flu

flu

flu

fcAb

fcAb

tAa

cu

fcAb

fsAc

fcAb

cu

fu

cu

rf

fsAc

tAa

tAa

tAa

frZ

frZ

fsAb

fsAb

cu

fu

cfl

cf

cp

fcCBM

fcCBM

tAa

cfl

cp cu

rf

fu

fu

fu

cu

cfl

cf

cu

cp

fchQ

fsAa

fsAb

fsAc

fcCBM

s

fcAa

fcAb

flu

fu

frz

tAa

tAb

rf

fl1b

Veronica

Bonnevie

Britomartis

Chasma

Artemis 

Corona

Laverna Dorsa 

Biliku Dorsa

O'Connor

Colijnsplaat

Corona

Teteoinnan 

Corona

Jalgurik

ZHIBEK PLANITIA

Behn 

Yomile

Janyl 

Ivne

TMa

TMb

TMc

TMd

Bonnevie 

Veronica 

Jalgurik

Ivne

Yomile

Janyl

O'Connor

TMa

TMb

TMc

TMd

Artemis

Chasma

Behn

Teteoinnan 

Corona

fracture zone

Laverna Dorsa

Biliku Dorsa

Zhibek Planitia

–25°

–30°

–35°

–40°

–45°

–50°

135°

130°

125°

120°

140°

145°

135° 130°

125°

120°

140° 145°

150°

SCALE 1:4 711 886 (1 mm = 4.712 km) AT –25° LATITUDE

1:5 000 000 AT –34° and –73° LATITUDES

LAMBERT PROJECTION

500 400 300 200 100 0 KILOMETERS100 200 300 400 500

–50°

–40°

–25°

–30°

–35°

–45°

–25°

–30°

–35°

–40°

–45°

150°

–50°

Prepared on behalf of the Planetary Geology and Geophysics Program, 

Solar System Exploration Division, Office of Space Science, National 

Aeronautics and Space Administration

Edited by Carolyn A. Donlin

Cartography by Darlene A. Ryan

Manuscript approved for publication November 24, 2009

Any use of trade, product, or firm names in this publication is for descriptive 

purposes only and does not imply endorsement by the U.S. Government.

For sale by U.S. Geological Survey, Information Services, Box 25286, 

Federal Center, Denver, CO, 80225, 1–888–ASK–USGS

Digital files available at http://pubs.usgs.gov/sim/3099

Printed on recycled paper

Prepared for the

National Aeronautics and Space Administration

U.S. Department of the Interior

U.S. Geological Survey

Scientific Investigations Map 3099

Atlas of Venus: Artemis Chasma Quadrangle (V–48)

Pamphlet accompanies map

SEQUENCE OF MAP UNITS AND MAJOR STRUCTURAL EVENTS

material unit C

post-dates

units below

material unit B

predates

material above

C

B

A

KEY

Time transgressive

contact; units A

and B form timetransgressively,

but B dominently

post-dates A

Part of the local 

stratigraphic sequence 

over which a 

time-transgressive 

structural suite may 

have formed (solid 

line indicates greater 

confidence)

Nature of lower contact unknown or 

meaningless; no temporal meaning

Nature of upper contact 

unknown or meaningless; 

no temporal meaning

CRATER MATERIAL

TECTONIC AND FRACTURE

TERRAIN UNITS

RADAR

FLOW AND SHIELD MATERIAL UNIT MAJOR STRUCTURAL EVENTS

Penetrative fabric

TMa-d structural suites

Artemis Chasma structural suite

 Radial fracture suite

 Fracture zone suite 

 Concentric wrinkle ridge suite

75°

50°

25°

75°

25°

–25°

0°

50°

0°

0° 30° 60° 90° 120° 150° 180°

–25°

–50° –50°

–75° –75°

V–1

V–23 V–24 V–22

V–34

V–62

V–35

V–21

V–20

V–9

V–8

V–10

V–33 V–36

V–12

V–45 V–48

V–11

V–46 V–47

V–57

V–3

V–2

V–13

V–44 V–49

V–25

V–32 V–37

V–4

V–56 V–58

QUADRANGLE LOCATION

Photomosaic showing location of map area. An outline of 

1:5,000,000-scale quadrangles is provided for reference.

Descriptions of nomenclature used on map are listed at 

http://planetarynames.wr.usgs.gov/

DESCRIPTION OF MAP UNITS

CRATER MATERIAL

Crater fill material—Undifferentiated, low-backscatter, low-RMS 

slope material filling some impact basins. Interpretation: low 

viscosity, gently emplaced material that locally filled craters 

following impact crater formation

Crater flow material—Undifferentiated, high-backscatter material 

apparently flowing from some impact basins. Interpretation: 

Impact melt or fluidized ejecta created by bolide impact

Crater material, undivided—Moderate to high-backscatter, highRMS slope material. Interpretation: Near-field ejecta and structurally uplifted breccia associated with bolide impact

Crater central peak material, undivided—High-backscatter, highRMS slope material located near the center of some impact 

basins as isolated inliers. Interpretation: Structurally uplifted 

breccia or rebounded material associated with bolide impact

FLOW AND SHIELD MATERIAL

Flow material of Quilla Chasma—Low-backscatter, low- to 

moderate-RMS slope, lobate to gradational boundaries, extends 

into local topographic lows. Interpretation: Localized volcanic 

material sourced from structures related to Quilla chasma (V–36)

Flows and shield-related material a of Artemis—Low-backscatter, 

low RMS slope, pock-marked by shield edifices less than 5 km in 

diameter, sharp digitate boundaries with kipukas of unit tAa, 

located in the southwest region of Artemis. Interpretation: Localized thin, low-viscosity veneer of volcanic shields and associated 

deposits

Flows and shield-related material b of Artemis—Low-backscatter, 

low RMS slope, pock-marked by shield edifices less than 5 km in 

diameter, sharp digitate boundaries with kipukas of unit tAa, 

located in the southeast region of Artemis. Interpretation: Localized thin, low-viscosity veneer of volcanic shields and associated 

deposits radiating from a centralized source

Flows and shield-related material c of Artemis—Low-backscatter, 

low-RMS slope, pock-marked by shield edifices less than 5 km 

in diameter, sharp digitate boundaries with kipukas of unit tAa, 

located in the eastern region of Artemis. Interpretation: Localized thin, low-viscosity veneer of volcanic material associated 

with volcanic shields

Ceres, Bona, and Miralaidji Coronae flow material, undivided— 

Intermediate -to-low backscatter material of heterogeneous 

texture including digitate to lobate to homogeneous to mottle 

flows material. Interpretation: Lava flows related to Cere and 

Bona and Miralaidji Corona complex of V–37 (Diana Chasma 

Quadrangle); correlative with unit cCBM of V–37 (Hansen and 

DeShon, 2002)

Inari Corona flow materials, member 1b—Intermediate backscatter 

material of heterogeneous texture, cut by pit chains, shallow 

troughs and fractures. Interpretation: Lava flows related to the 

formation of Inari Corona and Virava Chasma of V–35 (Ovda 

Regio Quadrangle); correlative with unit fI1b of V–35 

(Bleamaster and Hansen, 2005)

Shield terrain material—Intermediate-to-low backscatter material 

of heterogeneous texture. Composed of distributed edifices and 

associated material that forms a locally thin layer. Interpretation: 

Composite shield-related volcanic materials

Composite flow material a of Artemis—Low-backscatter, low RMS 

slope, locally pock-marked by small shield edifices (less than 5 

km diameter), localized lobate flow fronts, deformed by 

magmatic troughs, local inliers of unit tAa, located in the western 

region of Artemis. Interpretation: Composite of volcanic flows 

emplaced after the formation of the basal terrains

Composite flow material b of Artemis—Very low to moderatebackscatter, low RMS slope, pock-marked by small shield 

edifices (less than 5 km diameter), localized lobate flow fronts, 

locally hosts fine-scale polygonal fabric near the eastern margin, 

contact with unit tAa is in general digitate where the contact is at 

high angles to the trend of the penetrative fabric of unit tAa and 

gradational where the contact is near parallel to the trend of the 

penetrative fabric; embays unit tAc on the southeastern margin, 

located in the eastern region of Artemis. Interpretation: Composite of volcanic flows emplaced after the formation of the stratigraphically lower terrains

Localized flow material, undivided—Low-backscatter, low-RMS 

slope material located in local topographic lows, commonly 

associated with small shield edifices (less than 5 km diameter). 

Interpretation: Localized flood-lava flows

Flows, undivided—Undivided, low to moderate-backscatter, 

low-RMS slope, texturally homogeneous, discontinuous radarboundaries, locally pock-marked by small shield edifices (less 

than 5 km in diameter), locally deformed by fractures, pit chains, 

and magmatic troughs. Interpretation: Composite of individual 

local to regional events, unlikely to represent a coherent stratigraphic unit across the entire map area

TECTONIC AND FRACTURE TERRAIN UNITS

Fracture terrain of Zhibek Planitia—Moderate to low backscatter, 

low regional relief, terrain exposed locally through surrounding 

regions, and marked by penetratively developed parallel 

fractures. Interpretation: Materials of unknown genetic origin 

deformed by regional and local tectonic structures prior to being 

locally covered

Tectonic terrain of Artemis, unit a—High to very high-backscatter, 

high RMS slope, host to dominantly northeast-southwest trending 0.3–0.6 km wavelength penetrative tectonic fabric of undetermined origin. Gradational contact with unit tAb. 

Interpretation: Local basal material with penetratively developed 

tectonic fabric

Tectonic terrain of Artemis, unit b—Moderate-backscatter, high 

RMS slope, host to dominantly northeast-southwest trending 

0.3–0.6 km wavelength penetrative tectonic fabric of undetermined origin and topographic ridges spaced 10–50 km. Gradational contact with unit tAa. Interpretation: Local basal material 

with penetratively developed tectonic fabric

RADAR UNIT

Radar facies—High backscatter radar facies marked by penetratively 

developed (that is, spaced at or below data resolution) tectonic 

fractures and flows(?). Major trends marked by lineaments. 

Interpretation: This facies does not represent a single coherent 

geologic unit formed at a specific time, or of a specific character. 

Radar facies representing a composite unit of tectonic fabrics and 

flows

MAP EXPLANATION

PRIMARY STRUCTURES

Crater rim crest

Shield (< 5 km)

Shield (> 5 km)

Pit crater

Pit chain

Channel

Shallow trough

Radar boundary

Flow direction

Flow front

Dome

SECONDARY STRUCTURES

Linear fracture

Concentric fracture

Ridge

Fine

Intermediate

Broad

Trough lineament

Other lineament

Double lineament

Graben

Wrinkle ridge

Scarp

Fold crest

Penetrative fabric

Interior penetrative fabric

Chasma penetrative fabric

Fracture zone fabric

Chasma boundary

OTHER SYMBOLS

Contact—Short-dashed where gradational

Penetrative fabric wavelenth measure

6,053

6,052

6,050

6,051

6,054

NW NE

0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400

Distance (km)

Topographic profile for A–A’

Vertical Exaggeration ~87x

6,053

6,052

6,050

6,051

6,054

A A'

Mean Planetary Radius (km)

B

120°

–25°

150°

–50°

120°

–25°

150°

–50°

120°

–25°

150°

–50°

120°

–25°

150°

–50°

120°

–25°

–50°

A

12,000 12,000

11,000

9,000

7,000

5,000

3,000

1,000

–1,000

–3,000

1.0

0.75

0.50

0.25

.125

0.0

0

5,000

1,300

1,100

900

700

600

500

300

200

0

–1,000

–3,000

Elevation, in meters

1.0

0.20

0.17

0.15

0.13

0.10

0.08

0.06

0.03

0.005

Reflectivity C D E

0.99

0.9

0.85

0.8

0.7

0.6

0.5

0.4

0.279

Emissivity

0.95

12

10

8

6

4

2

0.2

RMS Slope, in degrees

Figure 9. Diagram summarizing four hypotheses proposed to accommodate Artemis formation. See text for 

discussion.

150°

Predictions:

1. Southwest part of the trough 

formed prior to, and unrelated to, 

the northeast-southeast part.

2. The southwest trough should 

record focused right-lateral shear.

3. The northeast trough should 

record focused left-lateral shear. 

4. Interior volcanism predated 

subduction (no upper-plate volcanism as in the case of terrestrial 

subduction..

5. Normal faulting in the outer rise 

in response to bending of the 

subducting plate.

References: Brown and Grimm 

(1995; 1996), Schubert and 

Sandwell (1995), McKenzie and 

others (1992)

Predictions:

1. Trough and paired rises represent multi-ringed impact structure.

2. Artemis formed at ~3.9 Ga, and 

therefore it represents a large 

ancient track of crust.

3. Any prexisting interior deformation fabric was obliterated by the 

impact event.

4. All structures formed nearly 

instantaneously.

5. The trough exists, but it is buried 

from ~9:00-12:00.

6. Interior region should form a 

deep basin.

7. Outer rise should preserve some 

sort of eject deposits or evidence of 

eroded ejecta deposits.

Reference: Hamilton (2005)

Predictions:

1. Approximately 170 km 

northwest-southeast directed extension in the center exposes deep 

crustal and possibly mantle rocks.

2. Artemis’ interior is characterized 

by a dominant northwest-trending 

elongational ductile fabric.

3. A sharp transition should mark 

the postulated lower plate-upper 

plate boundary.

4. Does not address formation of 

the trough or the outer rise.

Reference: Spencer (2001)

Predictions:

1. Artemis interior, chasma, and 

outer rise are genetically related and 

form broadly contemporaneously.

2. Interior volcanism and deformation contemporaneous with annulus 

formation.

3. Trough forms coherently and 

migrates either inward or outward 

with time.

4. Lineaments cut and are cut by 

other interior lineaments and trough 

structures.

5. Lava flows overlap in time and 

space both with one another, and 

with local tectonic fabrics.

References: Griffiths and Campbell 

(1991), Hansen (2002), Smrekar and 

Stofan (1997)

?

? ?

multi-ringed?

central peak?

Subduction Metamorphic Core Complex Meteorite Impact Mantle Plume

Single rising plume

ejecta blanket?

Small scale

convection

or secondary diapirs

Explanation

trough outline

lineament

lava flow

Figure 8. Inverted left-look SAR image of western Artemis Chasma; inset shows location within map area. 

The approximately 10 km wide diagonal stripes in the SAR data represent data gaps in left-look SAR filled 

with lower resolution right-look SAR data. White lines indicate major trend of lineaments that define shallow 

troughs. Apparent right-lateral offset of trough lineaments across the chasma likely reflects shortening across 

the chasma, rather than true right-lateral displacement across the chasma.

0 50 KILOMETERS

1

2

1

2

Figure 7. Inverted left-look SAR image of the southwestern tectonomagmatic center, TMa; inset shows 

location within V–48 quadrangle. White lines highlight lineaments that appear to change trend as they cross 

a ridge. Deflection may be explained solely by radar artifacts with the westward “translation” of lineaments 

that sit upon the high to the north. Illustrations to right show predicted patterns of lineaments for both 

left-lateral and right-lateral simple shear deformation of preexisting lineaments (top), extensional structures 

formed coincident with shear (middle), and contractional structures formed coincident with shear (bottom). 

Gray boxes indicate geometries that are inconsistent with the lineament patterns shown in the SAR image. 

The two white boxes show interpretations that might be consistent with the SAR data (left-lateral shear), 

assuming simple shear across the break in slope (as interpreted by Brown and Grimm [1995].) Brown and 

Grimm (1995) call for right-lateral simple shear across this region within the context of the subduction zone 

hypothesis.

Left Lateral Right Lateral

Illumination

Direction

0 50 KILOMETERS

Figure 10. Mars Orbital Laser Altimetry (MOLA) of Hellas Planitia, Mars, and topographic profiles (100 

times vertical exaggeration) across Hellas Impact basin (D–D’ and E–E’). Compare with Artemis 

topographic profiles (B–B’ and C–C’) below figure 1. MPR, mean planetary radius.

45° E 60° E 75° E 90° E

MOLA

2.5

–8Kilometers above MPR

Kilometers above MPR

D

D

D’

D’

–8

0

4

5,000 kilometers

Vertical exaggeration ~100x

0°

–15°

–30°

–45°

15° W 60° E 75° E 90° E 105° E 120° E 135° E 150° E 0° 15° E 30° E 45° E

HELLAS PLANITIA, MARS

Figure 2. Lambert projection images of V–48 showing NASA Magellan mission data. A, Elevation 

data. The stretched scale emphasizes the range of topography across Artemis; the other scale allows 

for global comparison; B, Reflectivity; reflectivity is a measure of the efficiency of a surface in 

reflecting electromagnetic radiation; a value of 1.0 represents perfect, total reflection. The stretched 

scale emphasizes the range of reflectivity across Artemis; the other scale allows for global 

comparison. C, Emissivity; emissivity ranges from 0 to 1, and it provides a measure of how well an 

object approximates a perfect blackbody radiator. D, RMS (root mean square) slope. Image 2E is a 

structural sketch map highlighting tectonic patterns with regard to Artemis Chasma (hachured line); 

penetrative fabric (blue fields with purple lines mark trends; blue lines mark fracture trends) 

outcrops in the interior of Artemis, whereas radial fractures and faults (thick blue lines) and 

concentric wrinkle ridges (red lines) occur within the exterior region. Structures within Artemis 

Chasma parallel the trace of the chasma. Note that the chasma and exterior structures share a center 

point. Tectonomagmatic centers (TMa–d) lie within Artemis’ interior region, and they mark regions 

in which the penetrative fabric changes local trend.

120° 135° 150°

105°

–30°

–45°

–15°

GTDR

3

–0.5Kilometers above MPR

0

2.5

5

0 2,000

Distance (km)

4,000

(km)

Figure 1. Topography of V-48 and surrounding region showing Aphrodite Terra, major chasmata, and 

planitiae. Artemis Chasma marks the near circular trough in the center of the map; topographic profiles B–B’

and C–C’, with 100 times vertical exaggeration show the chasma, interior, and exterior regions with respect 

to one another; chasma marked by arrows on profile. Outline shows the location of V–48 map area. Labeled 

features clockwise from the top: TR, ribbon tessera; D, Diana Chasma; Da, Dali Chasma, TC, Teteoinnon 

Corona; ZP, Zhibek Planitia; IP, Imapinua Planitia; fz, fracture zone; LP, Laimdota Planitia, AP, Aino 

Planitia; J, Juno Chasma, Q, Quilla Chasma; and A, Artemis Chasma, which defines Artemis, and B, Britoniartis Chasma in Artemis' interior.

Geologic Map of the Artemis Chasma Quadrangle (V–48), Venus

By

Roger A. Bannister1 and Vicki L. Hansen1

2010

1

Department of Geological Sciences,

 University of Minnesota Duluth, Duluth, MN

A

A’

Figure 11. Three-dimensional diagram sequence showing a new hypothesis for Artemis formation 

and evolution that combines aspects of other hypotheses. Diagram oriented to look southward 

across Artemis. TMC, tectonomagnetic center. See text for discussion.

mantle thermal

anomaly

South

South

time 5

TMC

trough

TMC

Hybrid hypothesis

for Artemis evolution

time 1

South

global crust

zone of crustal thinning

broad mantle

upwelling

time 0

time 6

time 3

South

trough

time 2

South

trough

trough

time 4

South

South

trough

TMC