180900-90-180

180900-90-180

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21,249 METERS-8,208

SCALE 1:70,000,000

Utopiabasin

Argyrebasin

Thaumasiaplateau

Thaumasiahighlands

highla

nd-low

land

transiti

on zon

e

Tharsisregion/rise

Elysiumregion/rise

Hellasbasin

Isidisbasin

1-lHl

2-eHt 3-eAb

5-eAb

10-lHl

15-lHt

11-lHl

4-Av 8-lHt

18-HNt

21-lAv

28-Htu

27-AHtu26-Htu

25-AHtu

7-mNh

14-mNh

22-mNh

32-eNh 33-eNh

40-HNb

46-lNv

41-eAb

43-eNhm

47-lNv

39-lHb

38-eHv

45-eNhm

44-eHb

36-eNh

20-mNh

6-lNl

12-Hto

23-mNh

16-eHt17-lHv

9-lAv

30-lAHtu 29-lHv

37-Nhu

34-lNh

35-lNh

31-mNh

24-HNhu

42-eHv

48-Hp

19-mNh

13-lNhFigure 1. Topography of Mars showing (1) numbered locations of detailed crater counts for some units (red areas; see table 2 for crater count data and Platz and others (2013) for detailed discussion of results) and (2) extents of informally named geographic features (dashed lines). (Mars Orbiter Laser Altimeter digital elevation model; see pamphlet for description.)

MSL

Pathfinder

PHX

MER A

MER B

Viking 2

Viking 1

lApc

Hp

lNhlNhAp

AHi

Hp

Hp

ApuApu

Hpe

ApueNh

lNh

Nhe lNhAHi

Nhu mNh

lNhlNh

lNhlNh

mNhmNh

eHh

lNh

lNh

lNh

eNh

eNh

eNh

Nve

AHi

lNh

eNh

eHh lNh

lNh

mNh

lNhlNh

lNh

lNh

lNhAHi eNh

mNh

mNh

mNh

AHiNhe

HNhumNh

mNh

lNv

lNh

lNv

ANaeHh

HNb

AHiAHi

AHi

eNh

mNh

lNh

lNh

lNh

eHh

lNh

ANa

Nhe

Nhe

lNh HNhu

AHi

mNh

eNh

AHi

lNh

Nhu

Nhe

Nhe

lNheHvmNh

HNhu

lNhNhe

eAb

lNv

AHi

mNhm

eHv

lNh

Nhe

lNh HNtlNh

eNhm

HNt

lHveHv

mNhNhe

eNh

HNb

lHb

eNhm

lNh

lNh

eHb

lNh

lNh

mNh

Hve

mNh

mNh

Nhe

Nhe

lNh HNhuHNhu

lNh Nhe

AHi

Nve eHv

eNhAHi

eNhm

Nve

lNh

lNh

lNh

HNhulHv

AHi

Nve

eHh

Nve

lNh

HNhu

mNh

AHi

mNh

mNh

mNh

mNh

mNh lNh

lNh

Nve

Nhe

eNhm

mNh

eNh

lNh

eHv

lHv

eNh

lNh

lNh

mNh

eNh

eNh

lNh

AHi

lNh

eNh

lNv

lNh

Htu

lNh

eNh

mNh

lNh

eNhlNv Nhu

Htu

Aa Aa

Aa

Aa

Ht

NhueNh

lNhmNh

Hve

lHt

lHvf

lHt

Htu

eHh

AHi

Nhu

eHv

NveeNhAa

Hto

Hto

Nhu

lNhAve

lNh

HtuHtu

Nhu

Htu

eHteHt

Nhu

HtulAa

eHv

mNh

AHi

eHtlNh

lNh

Nhe

AHiHNhu

Ht

eNh

eHhlHv

eNh

lHv

lAvfeHh

lNh

AHtu

AHtu

AHieHh

Htu

lNh

lHt

Htu

AHtu

Ht

Nhu

eNh

Htu

Hve

Htu

Htu

mNhm

mNhm

mNh

lHt

eNh

lHt

mNh

HNtlHvlAa

eHv

mNhm

mNhm

lHt

Ht

mNh

Hto

AHi

lAvfAHi

eHv

mNh

HNt

HNhu

Ht

lHt

Aa

lNh

lNh

HNt

Ht

HNt

lHvfNhu

mNh HNhu

Ht lNhAve

Hto

lHv

eNh

lHv lNh

lAv

lAvf

AHtu

eNh

AHtu

Hto

Hve

mNhm

lHvf

eHt

eHt

HNt

Nhu

eHt

mNh

eHtlAa

AHv

lNh

Ave

eHv

HNt

eNh

eHh

lHt

mNhlAv

eHh

eHh

lHvf

eHv

eHv

lHv

eNh

lHv

eNhHveHve

eHv

lAvf

lNhlAv

lHt

Nhu

eHt

eNheNh

Hve

lAv

lNh

HNt

Aa

eNhAHi eHteHh

lNh

AHv

lHt

Hto

lNhlHt

HNt

lHt

mAl

mNh

HNt

lHvf

ANa

eHh

mNh

mNh

lAv

eHv

eNh

lNh

ANa

Av

Av

ANa

lHt

Av

lHv

ANa

lHl

lHl

mAl

HNteHt

lHt

ANa HNtHNt

eHt

AHi

eAblNh

ANa HNt

lHt

mNh

mAl

AHi

Av

AHi

AHv

mAl

mAllHt

lHt

lHl

mAl

Hpe

Hpe

lApd

Apu

lHl

lHl

lHl

mAl

lApdlApdHpu

ApuApu lApc

lApclApc

eNh

eNh

Apu

Av

AHtu

lNh

AHi

Acidalia

Mensa

Phlegra

Montes

Sisyphi Planum

M A L E A

P L A N U M

P L A N U M A U S T R A L E

Cavi

Angusti

O l y m p i a U n d a eO l y m p i a U n d a e

Lomonosov

V A S T I T A S B O R E A L I S

P L A N U M B O R E U M

A R C A D I A

P L A N I T I A

Milankovic

ALBA

MONS

Cer

aun

ius

Foss

ae

T E M P E T E R R A

A C I D A L I A

P L A N I T I A

Deutero

ni lus

Mensa

e

Protoni lus Mensae

Lyot

U T O P I A P L A N I T I A

Mie

A M A Z O N I S

P L A N I T I A OLYMPUS

MONS

ASCRAEUS

MONS

MONS

PAVONIS

L U N A E

P L A N U MX A N T H E

C H R Y S E

P L A N I T I A

Becquerel

A RA B

I A

T E

R RA

M E R I D I A N I

P L A N U M

Cassini

Antoniadi

Nili

Foss

ae

S Y R T I S

M A J O R

P L A N U M

I S I D I S

P L A N I T I A

Am

enth

es

Foss

ae

ELYSIUM MONS

T E R R A

Medusae

Fossae

T E R R A

D A E D A L I A

P L A N U M

ARSIA

MONS

THAR

SIS

MON

TES

S Y R I A

P L A N U M

S I N A I

P L A N U M

S O L I S

P L A N U MP L A N U M

T H A U M A S I A

V A L L E S

M A R I N E R I S

Claritas

Fossae

T E R R AM A R G A R I T I F E R

T E R R A

Holden

Dollfus

Schiaparelli

Huygens

Scy

lla

S

cop

ulu

s

S A B A E A

Terby

Oenotria

Scopuli

HADRIACUSMONS

T Y R R H E N A

T E R R A

H E S P E R I A

P L A N U M

Gale

Gusev

APOLLINARISMONS

T E R R A

Ma

adim

Va

llis

Newton

Lowell

I C A R I A

P L A N U M

A O N I A

T E R R A

A R G Y R E

P L A N I T I A

N O A C H I S

T E R R A

Galle

Lohse

PeneusPatera

PateraAmphitrites

H E L L A S

P L A N I T I A

P R O M E T H E I

T E R R A

Wallace

C I M M E R I A

S I R E N U M

Ache

ron Fossae

Nocti

s Labyrinthus

TYRRHENUSMONS

LIBYA MONTES

Hel

lesp

ontu

s M

onte

s

NilosyrtisMensae

Echu

s C

hasm

a

Mawrth Vallis

Ares Vallis Nepenthes

Mensae

Nepenthes Planum

Marte

V

allis

EL Y S I U M P L A N I T I

A

Cerberus Fossae

Noctis

Fossae

Man

gala V

alles

Kasei

Valles

OY

Y OOY

YO

OY

YO

Y O

OY

YO

OY

YO

YO

OY

YOYO

YO

YO

OYYOO

Y

OY

OY

YO

YO

YO

OY

OY

YO

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Apu

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Nhu

AHi

lNh

mNh

lNh

AHi

lNh

mNhm

mNh

mNh

mNh

eHh

lNh

eNh

lNh

lNh eNhm

eNh

eNh

P L A N U M

A U S T R A L E

Chasm a Aust

rale

Promethei ChasmaUltimum Chasm

a

CaviAngusti

Promethei Rupes

Dorsa Argentea

Sisyphi PlanumOY

YOO

Y

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Scandia

Tholi

Olymp

ia Undae

Ru

pes

T

enui

s

Scan

dia

Cavi

Chasma

Boreale

mAl

AHi

mAl

mAl

lHt

AHi

AHi

AHi

lHl

Hpe

lApd

Apu

lHl

mAl

lApd

Hpu

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AHV

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OY

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DESCRIPTION OF MAP UNITS

UNIT NAME AND DESCRIPTION (coordinates of center(s) of type area(s) and, where available, counting localities (fig. 1 and table 2))

ADDITIONAL CHARACTERISTICS

INTERPRETATION

LOWLAND UNITS[Materials occupying northern lowlands (mostly 5,000 to about 4,000 m in surface elevation; low kilometer-scale surface roughness)]

Middle Amazonian lowland unitHummocky to undulating; grades into fields of knobs. Internally stratified. Tens of meters thick. (lat 51.43 N., long 118.45 E.)

Distributed within Vastitas Borealis and other northern plains; makes up the platforms of nearby pedestal-crater forms and perhaps whorled, low-re-lief ridge systems (thumbprint terrain, unmapped). Superposes units Av, AHv, eAb, lHl, lHt, Hpe, Hve, HNt, eHt, lNh, and mNh; underlies unit lApd; relation with unit Apu unclear

Ice-rich loess. Periglacial modification formed thumbprint terrain

Late Hesperian lowland unit Planar to undulating; lobate and troughed marginal areas in places. Hundreds of meters to kilometers thick. (lat 21.40 N., long 118.20 E.; localities 1, 6, 10, 11)

Continuous across most of the northern plains. Embays units lHt, Hto, eHt, eHv, HNt, lNh, mNhm, and mNh; superposed by units AHv, Av, eAb, Apu, mAl, lAv, and lApd; temporal relation to units Hpe and Hpu unclear. Contains hundreds of superposed pedestal-crater forms, thumbprint terrain, topographically sub-dued wrinkle ridges, and narrow grabens northeast of Alba Mons

Fluvial/lacustrine/marine and colluvial sedi-ments sourced from circum-lowland outflow channels and bounding highland terrains; likely intercalated with and underlain by lava and volcaniclastic rocks. Pervasively modi-fied and obscured by periglaciation, sedi-mentary diapirism, and particulate mantling

IMPACT UNIT

Amazonian and Hesperian impact unitCraters with rims and sur-rounding blankets; some include single to multi-lobed blanket forms, dense secondary crater chains, and (or) central peak or pit. Blanket thicknesses of meters to a few hundred meters. (lat 23.17 N., long 207.77 E.)

Global occurrence. Superposes Noachian units; other unit superposition relations diverse. High kilometer-scale surface roughness; crater floors may be smooth to rough

Upturned, ejected, and brecciated target rocks and sediments, with local areas of impact melt. Post-impact mass-wasting and fluvial-lacustrine and eolian infill of craters common

POLAR UNITS[Mostly ice, dust, and other fines at polar latitudes; north polar outcrops occur within the northern lowlands and south polar outcrops are within the southern highlands. Some of the units have a relatively low dielectric constant consistent with water ice and water ice and dust mixtures]

Late Amazonian polar cap unitHummocky and pitted at meter (northern cap) to hundreds of meter (southern cap) scales. Very high albedo except on pit floors. Mostly 10 km; narrow,