There are six sediment-landform assemblages.

Assemblage 1: Glacier ice and snow.a. Glaciers

(cirque, dome, tidewater, valley)

a. Perennial snow

Assemblage 2: Last Glacial Maximum

a. Drift sheet with isolated granite boulders;

b. Sandstone and siltstone breccia;

c. Coastal drift sheet with abundant erratics;

d. Patches of drift on sculpted cols and passes, with abundant erratics;

e. Moraine fragments and ridges;

f. Marine terrace.

Assemblage 3: Mid-Holocene.

a. Boulder train from Whisky Glacier to Brandy Bay;

b. Drift sheet (basalt pebble-cobble gravel);

c. Moraine in Brandy Bay;

d. Degraded moraine (in front of Whisky Glacier).

Assemblage 4: Late Holocene.

a. Ice-cored moraines

b. Abandoned cirques

Assemblage 5: Paraglacial.

a. Scree slopes;

b. Rivers, streams and lakes;

c. Pebble-boulder lags;

d. Spits;

e. Beaches and coastal boulder lags.

Assemblage 6: Periglacial.

a. Rock glacier;

b. Protalus rampart;

c. Freeze-thaw products;

d. Blockfields on mesas;

e. Slope processes.

7. Conclusions• This holistic and systematic sediment-landform study on the Ulu Peninsula,

James Ross Island, has used detailed sedimentary descriptions, geomorphology

and clast shape-roundness and lithology data to present the first landsystem

model for the northern Antarctic Peninsula.

• The availability of water leads to significantly different sediment-landform

assemblages than in other, drier and colder, parts of Antarctica. Periglacial and

paraglacial processes have significantly modified the glacial landscape.

• This research presents new data for the interplay between cold-based and warm

based ice, and presents significant new data regarding subglacial conditions and

the basal thermal regime during LGM glaciation.

• This data challenges the paradigm that cold-based glaciers do not erode or

deposit, but rather result in an identifiable sediment-landform assemblage.

2. Aims and Objectives1. To describe and determine past and present sediment-

landform process relationships;

2. To provide a modern analogue to aid interpretation ofpalaeo landsystems;

3. To present new data regardingthe character and behaviour ofthe Antarctic Peninsula Ice Sheetthrough the LGM and Holocene.

1. Rationale• Polar deserts are now, and would have been at the LGM, important and widespread landsystems in both the northern and

southern hemispheres.

• The interrelationship of processes (glacial, periglacial, paraglacial) is poorly understood. In particular, there have been few

studies of cold-based glaciers on soft beds.

• This new landsystem here can be used as a modern analogue to interpret landforms deposited in palaeo environments.

• Palaeo ice sheet reconstructions require a thorough understanding of current and past processes and subglacial

conditions. There is sparse information regarding the subglacial thermal regime during the LGM in the northern Antarctic

Peninsula.

3. Study area• Our geographical focus is the Ulu Peninsula,

James Ross Island, which has a well-preservedrecord of glacier fluctuations, but one that islargely unexploited.

• James Ross Island is composed of Cretaceoussedimentary strata, overlain by the NeogeneJames Ross Island Volcanic Group, whichcomprises basalt deltas (forming mesas), tuffs,and glacigenic diamictites.

• The Ulu Peninsula is largely ice-free, with severallarge glaciers draining Dobson Dome.Precipitation is around 200 m per year and meanannual temperatures are -5°C to -7.5°C, makingthis a polar desert.

• Granite erratics from Trinity Peninsula arereported to be distributed across the island.

A polar, arid, glacial-periglacial-paraglacial landsystem for James Ross IslandBethan Davies, Neil Glasser, Jonathan Carrivick, Mike Hambrey, John Smellie

bdd@aber.ac.uk

4. Methods4.1 Field Methods

• 7-week onshore field campaign (January to March 2011) with one field camp at Monolith Lake, Ulu Peninsula, James Ross Island.

• Geomorphological mapping, structural glaciology, sedimentological analysis, logging of ice-cored facies.

• 101 shape-roundness and lithology counts, each of 50 clasts, on a variety of different landforms.

4.2 Remote-Sensing Methods

• Data sources: ASTER and SPOT-5 satellite imagery, BAS aerial photographs, and DEMs created by the SPIRIT programme and by the Czech Geological Survey.

• Detailed geomorphological and glaciological maps were created for the study region.

• Identification of features followed standard procedures (Glasser et al., 2008; 2009).

• These maps were ‘ground-checked’ during fieldwork.

6. Discussion

6.1 A glacial-paraglacial-periglacial landsystem

Geological and glaciological studies on James Ross Island resulted in the

development of a new landsystem model, which will aid interpretation of

other palaeo-glaciated environments.

LGM glacial sediments have been reworked throughout the Holocene by

paraglacial and periglacial processes.

Abundant meltwater, streams and freeze-thaw encourages periglacial

processes, including patterned ground, gelifluction and frost shattering.

6.1 The Antarctic Peninsula Ice Sheet during the LGM

The glacial drift sheets here suggest difference s in the thermal regime under

the LGM ice sheet:

• Facies 2a. Widespread basalt cobble-gravel. Deposited by a cold-based ice

sheet; slow sheet-flow. Typical sediment-landform assemblage, similar to

that found in the Dry Valleys, East Antarctica.

• Facies 2b. Scoured bedrock; slow flow under a cold-based ice sheet.

• Facies 2c: Erratic-rich drift on cols and passes. Warm-based ice sheet; slow

sheet flow. Obstacles and focussed flow encourage basal melting.

• Facies 2d: Erratic-rich drift in coastal regions. Warm-based ice sheet; ice

streaming. Lateral margins of the Prince Gustav Ice Stream during the

LGM. Sharp boundaries in the thermal regime result in sharp onshore

facies transitions.

5. Landsystem Development

Geological map of the region, indicating field work location.

Source regions of granite erratics are shown in red. Basecamp by Monolith Lake. Lookalike Peaks and the large, degraded ice-cored moraine

of Whisky Glacier are in the background.

Geomorphological map of the Ulu Peninsula, Brandy Bay region.

Facies 3a: hyaloclastite boulder train. Photo taken

from the crest of Whisky Glacier moraine, looking

towards Brandy Bay.

Facies 4a: San José

Glacier and prominent

ice-cored moraines.

8. AcknowledgementsWe gratefully acknowledge the logistical support provided by BAS. We were deployed

by the RRS Ernest Shackleton and uplifted by the RRS James Clark Ross. We thank Alan Hill (BAS FGA) for

assistance in the field. This project is funded by NERC grant AFI 9/01 (NE/F012942/1). We thank the Czech

Geological Survey for providing access to their 2006 DEM, aerial photographs and map. The team

acknowledge support from Alpkit, who provided down jackets and other clothing.

Neogene tillites are well preserved

on the island, and were

redistributed as glacial erratics

across the surface. Some of these

tillites contain granite boulders,

which could have been reworked

by Quaternary glaciers. This one

was part of the boulder train.

Facies 6d. Blockfield

on top of Lachman

Mesa.

The team. From left: Bethan Davies, Alan Hill

(FGA), Neil Glasser and Jonathan Carrivick.

� � � � � � � � � � � �� � � � � � � � � �� � � � � � � � � � ! � " � � � # $% &' '() * + , - . / 0 1 2 3 4 5 6 7 4 38 9 :; < = > ? < @ >A B C DE F G H I JK L MN O P Q R ST U V W X Y Z [ X \ ] ^ X _ _` a b cd e f eg b ah i j k l m n ko p q q r s t uv w x xy z { | } ~ � � � � | � } z | � � � � � � � � � �� � � � � � � �� � � � �� � � � � � � ��   ¡¢ £ ¤¥ ¦ § ¨© ª «¬ ­® °̄ ± ² ³ µ́¶ ¶· ¸ ¹ º º » ¼½ ¾ ¿ ÀÁ Â Ã Ã Ä Å Æ Ç È Æ É È ÊË Ì Í Î Ï Ð Ñ Ò Ó Ô ÏÕ Ö × Ø Ù Ú Û Ü Ý Û Ü

Þ ß à á â ã ä å æ å ç è é ê ë ìí î ï ï ð ï ñ ò ó ôõ ö ÷ ø ö ùú û ü ý þÿ � � � �� � � ��� � � � � �� � � �� � �� � � � � � � �� � � � ! " # $ % & ' ( ) * + ,- . / 0 1 2 3 4 5 5 6 7 89 : ; < = > ? @A B C D EF G H I J K L M NO P Q R S P T TU V W X YZ [ \ ]^ _ ` a b c d e f gh if j k l mn o p q r r ql rs m tu v w xy z{ y y |y }v ~ � � �� �� � ��� �� � �� � � � � � �� � � � � �� � � � �� �   ¡ ¢ £¤ ¥ ¦ ¦ §¨ © ª « ¬ ­® ¯ ° ± °® ²³ ´ µ ¶ µ· ¸ ¹º » ¼ ½ ¾¿ À Á Â Ã Ä Å Æ Ç È É ÊË Ì Í Î Ï Ð ÑÒ Ó Ô Õ Ö × ×Ø Ù Ú Û Ü Ý Þ ß à á â ã ä å ã æ çè é ê ë ì í îï ð ñ ò ó ô õö ÷ ø ù ú û ü ý þ ÿ � � � �� � � � � � � � � � � � �� � � � � � � � � � � � � � � � � ! " # $ % & '( ) * + , - . / + 0 + 1 23 4 5 6 7 5 89 : ; ; < => ? @ A B C D E F G HI J K K LM N O P Q R P S S T U V W X Y Z[ \ ] ^ _ `a b c cd e f g h i j k l

m n o p q r s t s u r v w x y z{ | } ~ � �� � � � � � �� � � � � � � � � � � � � �� � � � � �� � � � �  ¡ ¢ £ ¤ ¥¦ §¨ © ª ª « ¬ ­ © ® ¯ ° ± ² ³ ´ µ ¶ ·

¸ ¹ º » ¼ ¼ ½ ¾ ¿ À Á ÂÃ Ä Å Æ Ç È É ÊË Ì Í ÎÏ Ð Ñ Ò Ó Ô Õ Ö × Ø ÙÚ ÛÚ Ü Ý Þßà á â ãä ä ã åæ çè éê ëì íî ì

ï ð ñ òó ô õ ö

÷ ø ù úû ü ý þ

ÿ � � �� � � ��� �� � �������� ������ ��� !" #$%&' () * +, - . /0 12 3 42 5

6 78 9 : ; <= > ? @ A B C D EF GHI H JK L M I HI N O PQ R S TU V WX V V YV ZS [\] ^ _ ^ ` ab cd e fg h ie gj k k l m n o pn q rstu v w xu y z{ | } ~ } �� ��� � � � �� � � �� � �� �� � �� � ��� �� �� � � � �� �� � � ���  ¡ ¢ £¤ ¥¦ § ¨ ¦ ©¦ª « ¬­ ® °̄ ® ® ±® ²« ³´ µ ° ²¶ « ³ ·¶ ¸ ¹° º »¼½ ¾ ¿À Á  ÃÄ ÅÆ ÇÈ É ÂÀ Á Ê Ë ÌÍ Î Ï Ð Í Ñ ÒÓÔ ÕÖ ×Ø Ù Ö Ú ÛÜ Ý Þ Û ×Ú ß àÜ áâã äã å æ çè é äè ê ëì íî ïð ñ ì òó í ô õ ö ÷ø ù ù úûü ý þÿ � � �� � � ý �� � �� � � � � � � �� � � � � � �� � �� � � �� � �� � � �� � ! " # " $% &' # " #( ) *+ , !- ) .

Monolith Lake with San Jose Pass

in the distance, looking towards

Santa Martha Cove. Note the

smoothed and sculpted slopes,

across which are distributed rare

granite erratics.

Facies 2b: sandstone breccia. Note the basalt

stone stripes resulting from periglacial weathering.

Facies 2d: coastal erratic-rich deposits, with a

sharp transition to basalt cobble-gravels, neck of

the Cape Lachman promontory, northern JRI.

Protalus ramparts