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HINEMOA PLANITIA

Gashan-Ki

Corona

Taranga Corona

Serova

Patera

Wyrd

Mons

Acrea Corona

Nazit Mons

Hecate Chasma

Hecate Chasma

Rind

Corona

Prthivi

Corona

Ak-Ene

Corona

Pajan Yan 

Tholus

Aruru Corona

Lama

Tholus

Paoro Tholi

Žverine Chasma

Nei-Teukez

Corona

Sinlaku

Corona

Polik-mana

Mons

Xochiquetzal

Mons

Tari Pennu

Corona

Nipa Tholus

Iaso Tholus

Ixtab

Mons

Shulzhenko

Patera

Kono Mons

Pat

Leyster

Yvette

Higgins

Akeley

Hanwi Chasma

Beecher

Montez

Wheatley

Baranamtarra

Asteria Regio

Ul’yana

Nuriet

Johanna

Gaze

Alina

Sobra Fluctus

Garbo

Patera

fPY fPa2 fM

plH psH

pA pcH

pmH

puH

peH

pfH t

phH c

fR

fPa1

fSh

fNi fSo fH

ef

vc

fG fAl

fSe

fK

fW

fX fL fIx

fPoc

fPoa

fIa1

fNa1

fPob fIa2 fNa3

fNa2

fPr

fAE fSib

fSia

fSid fArd

fArc

fAra

fArb

fSic

fGK1

fGK2

fAc1

fAc2 fTP1

fTP2

fTa

fTb

fNT1

fNT2

peH

fH

fH

fW

psH

peH

peH

peH

peH

fArc

fArb

fArb

fArd

fPa1

peH

peH

fK

peH

fPoa

fH

fPa2

psH

fPob

psH

peH

peH

peH

fH

fH

fPoc

psH

fAra

c

pfH

pA

pA

pA

pA

pA

pA

phH

phH

fSo

c

c

fGK1

fGK2

phH

fIx

c

fNa2 fNa1

fNa3

pfH

t

t

fSe

c

fTb

fTb

psH

fR

fPr

fPr

fTa

c ef

fNT2

fNT1

phH

phH

pfH

fAE

fNi

fPY

puH

pfH

pmH

puH

c

c

fG

fTP2

fTP1

fX

pfH

puH

pfH

pfH

fL

pfH

pfH

c

c c

fSib

fSia

fSic

fSid

vc

vc

c ef

pcH

pfH

pfH

psH c

phH

pfH

psH

psH

pfH

pfH

phH

fAc1

fAc2

pcH

pcH

pcH

pcH

vc

ef

fIa2

fIa1

phH

psH

vc

puH

pmH

pmH

fTb

pfH

vc

plH

plH

psH

pfH

pA

vc

vc

ef

pfH

fSh

psH

vc

vc

psH

phH

ef

ef

pmH

pA

t

vc

vc

fAl

vc

vc

pcH

pfH?

vc

c

vc

fG

ef

fTP1

puH

fH

vc

fM

fPY

fK

fSe

fW

fAl

fX

fL

fIx

fNa3

fNa2

fNa1

fH

ef

fSh

vc

fPoc

fR

fM

fPr

fSid

fSic

fAE

fSib

fAra

fGK2

phH

puH

peH

pfH

t

c

fNT2

fNT1

fGK1

fTP2

fTP1

fAc2

fAc1

fTb

plH

psH

fTa

pA

pcH

pmH

fSia

fPob

fPoa

fPa2

fPa1

fG

fIa2

fIa1

fNi

fArd

fArc

fArb

fSo

ef pcH

SCALE 1:5 198 991 (1 mm = 5.199 km) AT 0° LATITUDE

1:4 711 886 AT 25° LATITUDE

MERCATOR PROJECTION

500

25°

15°

0°

5°

10°

20°

400 300 200 100 0 KILOMETERS 100 200 300 400 500

240° 245° 250° 255° 260° 265° 270°

240° 245° 250° 255° 260° 265° 270°

25°

20°

15°

10°

5°

0°

25°

20°

15°

10°

5°

0°

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 Theresa Iki

Cartography by Darlene A. Ryan

Manuscript approved for publication May 10, 2011

Descriptions of nomenclature used on map are listed at 

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

Printed on recycled paper

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/3163

Geologic Map of the Hecate Chasma Quadrangle (V–28), Venus

By

Ellen R. Stofan,1 John E. Guest,2 and Antony W. Brian2

2012

1

Proxemy Research, Rectortown, VA

2

University College, London, UK

SEQUENCE OF MAP UNITS

TESSERA

MATERIAL

CRATER

VOLCANIC EDIFICE AND FLOW MATERIAL MATERIAL

Scientific Investigations Map 3163

Atlas of Venus: Hecate Chasma Quadrangle (V–28)

Pamphlet accompanies map

CORONA MATERIAL PLAINS MATERIAL

75°

50°

25°

75°

25°

–25°

0°

50°

0°

180° 210° 240° 270° 300° 330° 360°

–25°

–50° –50°

–75° –75°

V–1

V–29 V–30 V–28

V–40

V–62

V–41

V–27

V–26

V–15

V–14

V–16

V–39 V–42

V–18

V–51 V–54

V–17

V–52 V–53

V–60

V–6

V–5

V–19

V–50 V–55

V–31

V–38 V–43

V–7

V–59 V–61

QUADRANGLE LOCATION

Photomosaic showing location of map area. An outline of 

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

DESCRIPTION OF MAP UNITS

VOLCANIC EDIFICE AND FLOW MATERIAL

Pajan Yan Tholus material—Low- to intermediate-backscatter, sheet-like, lobate 

deposits occurring on the summit and flanks of Pajan Yan Tholus. Superposes 

units phH, fAE, and puH. Type locality: Lat 8° N., long 252.5° E. Interpretation: 

Lava flows from central or flank vents of the Pajan Yan edifice

Kono Mons material—Intermediate- to high-backscatter digitate deposits on the 

flanks of an edifice cut by Zverine Chasma. Type locality: Lat 20° N., long 269° 

E. Flows both superpose and are cut by fractures of Zverine Chasma. Superposes 

units pA and c. Interpretation: Lava flows from central or flank vents of Kono 

Mons

Serova Patera material—Variable backscatter materials with lobate boundaries and 

digitate to sheet-like form radiating from a circular depression. Superposes units 

phH, pcH, c, and fTb. Type locality: Lat 20.5° N., long 247.5° E. Interpretation: 

Lava flows from Serova Patera

Wyrd Mons material—Intermediate- to high-backscatter digitate deposits on the 

summit and flanks of Wyrd Mons. Superposes units phH, fTb, and psH. Type 

locality: Lat 13.8° N., long 247° E. Interpretation: Lava flows from central or 

flank vents of the Wyrd Mons edifice

Alcyone Tholus material—Sheet-like, lobate, intermediate-backscatter deposits that 

extend from Aleyone Tholus. Superposes units pmH and vc, superposed by unit 

fM. Type locality: Lat 0.3° N., long 257.5° E. Interpretation: Lava flows from 

central or flank vents of the Alcyone Tholus edifice

Xochiquetzal Mons material—Digitate, variable backscatter deposits on the summit 

and flanks of Xochiquetzal Mons. Superposes units puH, ef, and pfH. Type locality: Lat 3° N., long 269° E. Interpretation: Lava flows from central or flank vents 

of the Xochiquetzal Mons edifice

Lama Tholus material—Intermediate-backscatter, digitate to sheet-like deposits on 

the summit and flanks of Lama Tholus. Superposes units puH, ef, and pfH. Type 

locality: Lat 7.8° N., long 266° E. Interpretation: Lava flows from central or flank 

vents of Lama Tholus edifice

Ixtab Mons material—Intermediate- to low-backscatter, digitate to sheet-like deposits on the summit and flanks of Ixtab Mons on the margin of Hecate Chasma. 

Flows cut by faults of Hecate Chasma. Superposes units phH and fH, superposed 

by units psH and c. Type locality: Lat 16° N., long 243° E. Interpretation: Lava 

flows from central or flank vents of the Ixtab Mons edifice

Polik-mana Mons material, member c—Digitate deposits of variable backscatter on 

the flank of Polik-mana Mons. Superposes units fPoa, fH, pfH, and pA. Type 

locality: Lat 23° N., long 269° E. Interpretation: Lava flows from flank vents of 

the Polik-mana Mons edifice

Polik-mana Mons material, member b—Low-backscatter deposits in the central 

summit depression of Polik-mana Mons. Superposes unit fPoa. Type locality: Lat 

24.2° N., long 263.8° E. Interpretation: Lava flows ponded in the central caldera 

of the Polik-mana Mons edifice

Polik-mana Mons material, member a—Intermediate- to high-backscatter, digitate 

to sheet-like deposits on the summit and flanks of Polik-mana Mons. Partially 

deformed by but also superposing fractures of the Hecate Chasma rift. Superposes 

unit pA, embayed by units fPoc and fPob. Type locality: Lat 23.5° N., long 264° 

E. Interpretation: Lava flows from the central and flank vents of Polik-mana 

Mons

Paoro Tholi material, member 2—Variable backscatter, digitate and sheet-like 

deposits on the summit and flanks of Paoro Tholi. Superposes units fPa1, peH, 

puH, and vc. Type locality: Lat 10.5° N., long 268.5° E. Interpretation: Lava 

flows from central or flank vents of the Paoro Tholi edifices

Paoro Tholi material, member 1—Intermediate-backscatter, lobate and sheet-like 

deposits on the summit and flanks of Paoro Tholi. Superposes units peH and fArb

and embayed by unit fPa2. Type locality: Lat 10° N., long 267.5° E. Interpretation: Lava flows from central or flank vents of the Paoro Tholi edifices

Garbo Patera material—Intermediate-backscatter, sheet-like deposits flooding and 

surrounding a quasi-circular depression. Superposes units pmH, phH, puH, and 

vc, embayed by units psH, vc, and fM. Type locality: Lat 2.5° N., long 258° E. 

Interpretation: Lava flows from central vent of the Garbo Patera volcano

Iaso Tholus material, member 2—Intermediate- to high-backscatter, sheet-like 

deposits on the summit and flanks of Iaso Tholus. Superposes units fIa1, peH, 

puH, and pmH. Type locality: Lat 5° N., long 255° E. Interpretation: Lava flows 

from the central vent of Iaso Tholus edifice

Iaso Tholus material, member 1—Low- to intermediate-backscatter, sheet-like 

deposits on the flank of Iaso Tholus. Superposes units phH and pmH, embayed by 

unit fIa2. Type locality: Lat 4° N., long 255° E. Interpretation: Lava flows from 

the central or flank vents of Iaso Tholus edifice

Nipa Tholus material—Digitate deposits with variable backscatter on the summit and 

flanks of Nipa Tholus. Superposes unit phH, embayed by unit fAE. Type locality: 

Lat 8° N., long 256° E. Interpretation: Lava flows from central vent of Nipa 

Tholus

Sobra Fluctus material—Flow material having intermediate backscatter with low 

backscatter along some margins. Lobate boundaries. Superposes units phH, puH, 

peH, embayed by unit fR. Type locality: Lat 5° N., long 248° E. Interpretation: 

Lava flows from an unidentifiable vent

Nazit Mons material, member 3—Intermediate- to high-backscatter, digitate deposits 

on the flank of Nazit Mons. Superposes units fNa1, fNa2, pcH, phH, and pfH. 

Type locality: Lat 20.8° N., long 242.5° E. Interpretation: Lava flows from flank 

vents of the Nazit Mons edifice

Nazit Mons material, member 2—Variable backscatter, digitate and sheet-like deposits on the summit of Nazit Mons. Superposes units fAc1, fNa1, phH, and embayed 

by unit fNa3. Type locality: Lat 23° N., long 240° E. Interpretation: Lava flows 

from the central vent of the Nazit Mons edifice

Nazit Mons material, member 1—Intermediate-backscatter, lobate to sheet-like 

deposits on the flanks of Nazit Mons. Superposes units fAc1 and pcH and 

embayed by units fNa2 and fNa3. Type locality: Lat 22° N., long 243° E. Interpretation: Lava flows from central or flank vents of the Nazit Mons edifice

Hecate Chasma flow material—Digitate to sheet-like flow material with variable 

backscatter along the margins of Hecate Chasma. Multiple occurrences in map 

area with varying superposition relations. Type locality: Lat 12.5° N., long 242° 

E. Interpretation: Lava flows from fissures along Hecate Chasma

Edifice field material—Numerous small shields and cones surrounded by lobate 

deposits with moderate backscatter. Multiple occurrences in map area with 

varying superposition relations. Type locality: Lat 12.5° N., long 255.5° E. Interpretation: Volcanic edifice fields of varying ages

Shulzhenko Patera material—Intermediate- to low-backscatter, lobate deposits 

filling and surrounding a central circular depression. Superposes unit puH, 

embayed by units fL, fAra, and fArb. Type locality: Lat 7° N., long 264.8° E. Interpretation: Lava flows from central vent of Shulzhenko Patera

Volcanic complex material—Flow material with low to high backscatter and lobate 

boundaries. Multiple occurrences in map area with varying superposition 

relations. Type locality: Lat 2° N., long 261° E. Interpretation: Lava flows from 

central or flank vents of an unnamed volcanic complex

CORONA MATERIAL

Rind Corona material—Flow material with intermediate backscatter. Unit is ponded 

in the interior of Rind Corona, and extends to the surrounding plains. Superposes 

units fSo and phH. Type locality: Lat 2° N., long 261° E. Interpretation: Lava 

flows from the interior of Rind Corona

Miti Corona material—Lobate flow material with intermediate backscatter extending 

from Miti Corona. Superposes units puH, fG, fAl, and vc. Type locality: Lat 0° N., 

long 259° E. Interpretation: Lava flows that originated from vents in the flanks or 

interior of Miti Corona

Prthivi Corona material—Lobate flow material with intermediate backscatter, 

emanating from fractures along the rim of Prthivi Corona. Superposes units fTb

and phH. Superposes and is cut by Hecate Chasma faults. Type locality: Lat 13° 

N., long 250° E. Interpretation: Lava flows from fissures along the rim of Prthivi 

Corona

Ak-Ene Corona material—Flow material with intermediate backscatter with lobate 

boundaries, deformed by the rim and radiating fractures of Ak-Ene Corona. Flow 

material extends beyond the corona rim. Superposes units fTb, phH, and fNi, 

embayed by unit fPY. Type locality: Lat 9° N., long 254° E. Interpretation: Lava 

flows from Ak-Ene Corona deformed during corona formation

Sinlaku Corona material, member d—Intermediate backscatter sheet-like flow 

material with lobate boundaries. Superposes unit fSib. Type locality: Lat 18° N., 

long 260° E. Interpretation: Lava flows from a vent on the flank of Sinlaku 

Corona

Sinlaku Corona material, member c—Low backscatter lobate flow material in the 

interior of Sinlaku Corona. Superposes unit fSia. Type locality: Lat 16° N., long 

259.5° E. Interpretation: Lava flows from a vent within Sinlaku Corona

Sinlaku Corona material, member b—Digitate to sheet-like flow material with 

variable backscatter. Superposes units fNT1, pA, pmH, and psH and embayed by 

units vc and fSid. Unclear age relation with unit fSia. Type locality: Lat 17° N., 

long 262° E. Interpretation: Lava flows from Sinlaku Corona partially deformed 

by corona formation

Sinlaku Corona material, member a—Intermediate backscatter flow material on the 

plateau of Sinlaku Corona. Embayed by unit fSic. Unclear age relation with unit 

fSib. Type locality: Lat 17° N., long 260° E. Interpretation: Lava flows from 

central or flank vents of Sinlaku Corona

Aruru Corona material, member d—Digitate, variable backscatter flow material 

that forms a fan from the rim of Aruru Corona. Superposed on unit fArb. Type 

locality: Lat 10° N., long 264° E. Interpretation: Lava flows from a vent on the 

rim of Aruru Corona

Aruru Corona material, member c—Digitate to lobate flow material in the interior 

plateau of Aruru Corona with variable backscatter. Superposes unit fArb. Type 

locality: Lat 8° N., long 263° E. Interpretation: Lava flows from vents in the 

interior of Aruru Corona

Aruru Corona material, member b—Intermediate backscatter flow material with 

digitate to sheet-like form, deformed by the rim and fractures of Aruru Corona. 

Superposes units fSh, fAra, pfH, peH, phH, puH, and vc. Embayed by units fArc, 

fArd, fPa1, psH, and fL. Type locality: Lat 8° N., long 259° E. Interpretation: 

Extensive lava flow units of Aruru Corona deformed during corona formation

Aruru Corona material, member a—Sheet-like flow material with intermediate 

backscatter and lobate boundaries. Superposes units puH and fSh, embayed by 

unit fArb. Type locality: Lat 6.5° N., long 264° E. Interpretation: Lava flows 

originating from Aruru Corona

Gashan-Ki Corona material, member 2—Flow material with low to intermediate 

backscatter and lobate boundaries. Superposes and is cut by Hecate Chasma 

faults. Superposes units fGK1 and phH, embayed by unit fH. Type locality: Lat 

9.2° N., long 243.5° E. Interpretation: Lava flows from the flanks or interior of 

Gashan-Ki Corona

Gashan-Ki Corona material, member 1—Flow material and deformed material with 

variable backscatter and lobate boundaries. Superposes and is cut by Hecate 

Chasma faults. Superposes units fTb and phH, embayed by units fGK2 and fH. 

Type locality: Lat 11° N., long 244° E. Interpretation: Lava flows from Gashan-Ki 

Corona and possibly pre-existing plains materials that have been deformed by 

corona formation

Nei-Teukez Corona material, member 2—Flow material with intermediate backscatter in the interior low of Nei-Teukez Corona. Type locality: Lat 14° N., long 

258.5° E. Superposes unit fNT1. Interpretation: Lava flows from vents in the 

interior of Nei-Teukez Corona

Nei-Teukez Corona material, member 1—Intermediate backscatter lobate material. 

Superposes units peH, phH, and pmH. Embayed by units vc, fNT2, and fSib. 

Type locality: Lat 13.5° N., long 257.7° E. Interpretation: Lava flows originating 

from Nei-Teukez Corona

Tari Pennu Corona material, member 2—Flow material with intermediate backscatter in the interior of Tari Pennu Corona and extending beyond the rim. Superposes 

units fTP1, puH, and pmH. Type locality: Lat 1° N., long 264.5° E. Interpretation: Lava flows from central or flank vents within Tari Pennu Corona

Tari Pennu Corona material, member 1—Flow material with intermediate backscatter and lobate boundaries. Includes the deformed rim of Tari Pennu Corona. 

Embayed by unit fTP2. Type locality: Lat 0° N., long 264° E. Interpretation: Lava 

flows from Tari Pennu Corona partially deformed during corona formation

Acrea Corona material, member 2—Digitate flow material with intermediate 

backscatter located in a depression within Acrea Corona. Superposes unit fAc1. 

Type locality: Lat 24° N., long 241.5° E. Interpretation: Lava flows from within 

Acrea Corona

Acrea Corona material, member 1—Flow material and deformed materials with 

intermediate backscatter, and lobate boundaries. Includes the interior and 

deformed rim of Acrea Corona and exterior flow materials. Superposes units pA

and pcH, embayed by units fAc2, fNa1, and fNa2. Type locality: Lat 24° N., long 

243° E. Interpretation: Lava flows from Acrea Corona

Taranga Corona material, member b—Flow material with intermediate backscatter 

and lobate boundaries. Some portions of the unit are penetratively cut by Hecate 

Chasma fractures. Superposes units t, pA, pfH, and phH, embayed by units fSe, 

fGK1, fPr, fAE, fW, and c. Uncertain age relation with unit fTa, but in part older. 

Type locality: Lat 13° N., long 252° E. Interpretation: Deformed and undeformed 

lava flows from the center of Taranga Corona

Taranga Corona material, member a—Materials in the interior of Taranga Corona, 

some with intermediate backscatter, others with high backscatter marked by 

secondary structures. Uncertain age relation with unit fTb, but in part younger. 

Type locality: Lat 16° N., long 252° E. Interpretation: Lava flows from center of 

Taranga Corona that have been deformed during corona formation

PLAINS MATERIAL

Hinemoa lobate plains material—Generally flat-lying deposits with relatively 

uniform backscatter over hundreds of kilometers; minor occurrences of domes, 

cones, shields, fractures, and ridges. Superposed on pA. Type locality: Lat 25° N., 

long 257.2° E. Interpretation: Volcanic plains composed primarily of areally 

extensive flow units

Hinemoa smooth plains material—Areally limited deposits with relatively low radar 

backscatter, scattered small edifices and (or) pits. Embays all other plains units 

with which it is in contact (units pmH, peH, phH, pA, pcH) and units fArb, vc, 

fG, and fIx. Embayed by unit fSib. Type locality: Lat 20° N., long 244° E. Interpretation: Volcanic plains that have undergone little deformation

Asteria plains material—Extensive, generally flat-lying deposits with variable 

backscatter over hundreds of kilometers; occurrences of domes, cones, shields, 

and moderately spaced to closely spaced fractures. Superposed by phH, pcH, 

plH, psH, fPoc, fPob, fPoa, fK, fTb, fAc1, fSib, vc, fH, and ef. Embays unit pfH. 

Type locality: Lat 23° N., long 256° E. Interpretation: Volcanic plains composed 

primarily of areally extensive flow units cut by multiple suites of fractures

Hinemoa composite-flow plains material—Generally flat-lying deposits with 

variable backscatter with small volcanoes, fractures, and wrinkle ridges. Superposed by units psH, ef, vc, fSe, fNa3, fNa1, fAc1, embays unit pA and phH. 

Type locality: Lat 22° N., long 245° E. Interpretation: Volcanic plains of interfingered deposits that have been locally deformed

Hinemoa mottled plains material—Extensive deposits with variable backscatter 

characterized by numerous small edifices, fractures and wrinkle ridges. Superposed by units phH, psH, vc, fG, fAl, fIa2, fIa1, fTP2, and fSib. Embays units 

pfH and peH; differing age relations with different occurrences of unit puH. Type 

locality: Lat 3.5° N., long 264° E. Interpretation: Volcanic plains composed of a 

number of interfingered deposits, locally deformed

Hinemoa hummocky plains material—Extensive deposits with variable backscatter 

characterized by numerous small edifices, areas of closely spaced fractures, and 

wrinkle ridges. Cut by fractures of Hecate Chasma, and superposed by numerous 

coronae. Superposed by units pcH, psH, fH, vc, ef, fG, fSe, fSo, fIa1, fPY, fNi, 

fNa3, fNa2, fIx, fW, fArb, fR, fGK2, fGK1, fAE, fTb, and fPr. Superposes units 

puH, pA, pmH, pfH, and peH. Type locality: Lat 7° N., long 243° E. Interpretation: Volcanic plains composed of interfingered deposits that have been locally 

deformed, as well as penetratively deformed by Hecate Chasma faults

Hinemoa uniform plains material—Extensive, generally flat-lying deposits with 

relatively uniform backscatter over hundreds of kilometers; minor occurrences of 

domes, cones, shields, fractures, and ridges. Superposed by units phH, fTP2, fG, 

fIa2, fPY, fPa2, fL, fSh, fX, fSo, fM, fArb, and fAra. Embays units peH and pfH; 

differing age relations with different occurrences of unit pmH. Type locality: Lat 

1° N., long 268° E. Interpretation: Volcanic plains composed primarily of areally 

extensive flow units

Hinemoa edifice plains material—Limited extent, generally hummocky unit that 

exhibits low to high backscatter. Contains numerous small domes, cones and 

shields and associated lobate flows and fractures in multiple orientations. Superposed by fIa2, fPa2, fPa1, fSo, fArb, vc, psH, phH, puH, and pmH. Embays unit 

pfH. Type locality: Lat 6° N., long 257° E. Interpretation: Numerous small volcanic edifices and associated flows forming volcanic plains, cut by secondary structures. Occurs in multiple areas with indeterminate age relation between different 

outcrops

Hinemoa fractured plains material—Limited deposits with intermediate radar 

backscatter cut by closely spaced fractures. Typically higher standing and 

embayed by other plains units. Single orientation of fractures in an outcrop, but 

direction not consistent between outcrops. Superposed by phH, peH, pmH, puH, 

vc, fL, fX, fPoc, fNa3, fArb, and fTb. Type locality: Lat 23.5° N., long 248° E. 

Interpretation: Plains of probable volcanic origin cut by single suite of fractures. 

Occurs in multiple areas, indeterminate age relation between different outcrops

TESSERA MATERIAL

Tessera material—Generally high backscatter, locally high standing material with 

two or more orientations of lineaments; typical occurrences are small and appear 

to be embayed by plains and flow materials. Embayed by units phH, pcH, pA and 

fTb. Type locality: Lat 21° N., long 252° E. Interpretation: Extremely tectonically 

deformed, locally older materials embayed by younger volcanic plains and flows

CRATER MATERIAL

Crater material, undifferentiated—Intermediate to high backscatter, hummocky 

ejecta materials surrounding radar bright or dark floor, with crater rim, wall, and 

central peak. See table 2 for age relations. Type locality: Lat 16.5° N., long 268° 

E. Interpretation: Deposits and structures formed by hypervelocity impact

EXPLANATION OF MAP SYMBOLS

Contact—Dashed where approximately located

Lineament—Origin uncertain

Lineament associated with chasma—Parallels chasma trough

Lineament associated with corona—Typically rim fracture

Wrinkle ridge—Interpreted as compressional deformation

Broad topographic ridges or warps

Scarp—Line marks top of slope; hatchures point downslope

Steep-sided volcanic dome

Impact crater rim (diameter >10 km)—Hachures on rim crests

Impact crater (diameter <10 km)

Volcanic caldera—Dashed where partially buried

Volcanic edifice (diameter <5 km)

Flow direction

Flow front—Hachures point in flow direction

Surficial material—Radar-dark, diffuse deposit

Channel—Interpreted as formed by lava erosion

Prepared for the

National Aeronautics and Space Administration

Figure 1. Magellan topographic map of quadrangle V–28, extending from lat 0°–25° N., 

long 240°–270° E. The lowest regions are found in the rift trough (6048.5 km), and the 

highest regions along the rift rim (6056.1 km).

25°

240° 270°

0°

Figure 2. Magellan RMS slope roughness map of quadrangle V–28, extending from 

lat 0°–25° N., long 240°–270° E.

25°

240° 270°

0°

Figure 3. Magellan emissivity map of quadrangle V–28, extending from lat 0°–25° N., 

long 240°–270° E.

Figure 4. Portion of Hinemoa edifice plains material (unit 

peH) illustrating high concentration of small edifices within 

the unit, and the closely spaced lineaments that deform the unit. 

Black arrows indicate small edifices that postdate formation of 

the materials that make up unit peH and the fractures that 

deform the unit; white arrows indicate edifices that are cut by 

fractures that also cut the plains, illustrating that small edifices 

likely formed prior to the lineaments that cut the unit, as well as 

after the deformation that cuts unit peH. The image is approximately 100 km across; lineaments within the unit are spaced 

<10 km apart and are thus not mappable on the 1:5,000,000-

scale map. The origin of the closely spaced lineaments is 

unknown; we interpret them to be polygonal fractures. More 

widely spaced, less sinuous lineaments can also be seen cutting 

unit peH, trending NNW as well as NE, along with an older, 

relatively higher standing patch of radar-bright terrain that is 

embayed by unit peH.

Figure 5. Edifice field material (unit ef), characterized by 

small edifices surrounded by radar-dark flow deposits. These 

deposits truncate structures that cut Hinemoa composite-flow 

plains material (unit pcH), indicating that unit ef is relatively 

younger. Other structures cut both units, indicating ongoing 

deformation in the region. Unit pcH is cut by polygonal 

fractures, similar to unit peH. This image is approximately 40 

km across.

Figure 6. The volcano Kono Mons is cut in half by Zverine 

Chasma; the dashed lines indicate the location of the Zverine 

trough rim. Arrows indicate flows from Kono Mons, x’s 

indicate the approximate location of the topographic edifice 

split by the chasma.

25°

240° 270°

0°

0 5 10 15 20 25 0.6 0.7 0.8 0.9

Root-mean-square slope (degrees) Microwave emissivity

x

x

243.05° 244.15°

2.35°

3.38°

251.4° 251.8°

22.7°

23.1°

267° 270°

17.5°

21.5°

6,048 6,050 6,052 6,055

Planetary radius (km)

U.S. Department of the Interior

U.S. Geological Survey