HARDY ASSOCIATES CIB7EIJ LTD.

TERRAIN ANALYSIS OF THE DEMPSTER

For. Foothills Pipe Lines (Yukon) Ltd.

BY Hardy Associates (1978) Ltd.

February, 1979 K4239 HARDV ASSOCIATES ClB7BJ LTD.

TABLE OF CONTENTS

PAGE

1.0 INTRODUCTION 1 1.1 General 1 1.2 Sources of Data 1 1.3 Presentation of Terrain Data 2 2. O TERRAIN MAPPING 2.1 Principles of Terrain Mapping 3 2.2 Terrain Mapping Legend 5 3.0 PHYSIOGRAPHIC SETTING 8 3.1 Arctic Coastal Plain 9 3.1.1 Mackenzie Delta 9 3.2 The Interior Plains 10 3.2.1 Anderson Plain 10 3.2.2 Peel Plain 11 3.2.3 Peel plateau 12 3.3 Cordillera (Eastern System) 13 3.3.1 Richardson Mduntains 13 3.3.2 Porcupine Plateau 14

I 3.4 Cordillera (Interior System) 15 3.4.1 Ogilvie Mountains 15 3.4.2 Tintina Trench 16 3.4.3 Yukon Plateau 18 4.0 GEOLOGIC HISTORY 20 Be drock Geology4.1 Bedrock 20 4.1.1 Arctic Coastal Plain, Interior Plains and Cordillera (Eastern System) 20 4.2.2 Cordillera (Interior Systems) 21 Ogilvie Mountains 21 Tintina Trench 23 Yukon Plateau 24

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TABLE OF CONTENTS CON'T

4.2 Quaternary Geology 26 4.2.1 Arctic Coastal Plain and Interior Plaina 26 4.2.2 Cordillera (Eastern System) 28 4.2.3 Cordillera (Interior System) 30 Ogilvie Mountains 30 Tintina Trench 32 Yukon Plateau 34 5.0 CHARACTERISTICS OF TERRAIN UNITS. BY PHYSIOGRAPHIC REGION 36 6.0 REFERENCES 38

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I 1.0 INTRODUCTION

I 1.1 General I Terrain analysis, which includes terrain classi- I fication and mapping,was conducted by Hardy Associates (1978) Ltd., Calgary, Alberta, along the Dempster routeof I Foothills Pipe Lines (Yukon) Ltd. Basic information obtained I during terrain classificationand mapping describesand identifies 1) the bedrock and soils materials near ground surface, 2) geologic and engineering propertiesof these materials, 3) stratigraphy and permafrost characteristics of surficial materials, 4) geologic history of terrain units and landforms, 5) topography and drainage character- istics of landforms.

1.2 Sources of Data

Terrain analysisis based on airphoto interpre- tation and supplementedby published information, field investigations, and drilling programs. Terrain classification and mapping information appearsas the photomosaic portion of the alignment sheets. Geological and geophysical field investigations and drilling programs conducted during1977 and 1978 provided field information to substantiate airphoto interpretation.

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Ground reconnaissanceand field surveys included observations onlandforms, geologic materials, permafrost, vegetation, topography, drainage, and present erosional features .

Drilling and laboratory work provided information on soil and rock type, permafrost, moisture content, grain size, and other engineering properties. Thermistor strings were installed at selected localities to provide ground temperature data.

Reports and maps by the Geological Surveyof Canada, Department of Energy,.Mines and Resources, were the largest source of published information on bedrock and soil materials along the Dempsterpipeline corridor. Principal works are referredto in this report andare listed in the References Section.

1.3 Presentation of Terrain Data

The photomosaic alignment sheets preparedby Hardy Associates (1978) Ltd. during 1978 show the distribution and characteristics of terrain units along the pipeline corridor. This information is supplemented by reports on geophysical surveys and drilling programswhich were prepared for Foothills Pipe Lines (Yukon)Ltd. and have these titles:

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3) ' Demp.ster Lateral Ga's Pipe'lin'e.P'rQje.ct .-' Pe'rhafrbst 1 Delineation Geophys.i'c'a'1:S'Wvey, .Dec.ember 1978, Hardy and Associates (1978) Ltd.

Further information on the terrain typing system developed for the Dempster route is described in this report. Also data on physiography,.,geologic history, geologic processes, and major terrain units along the pipeline corridor are discussed here.

2.0 TERRAIN MAPPING.

2.1 ' Princ.iples''of Te'rEain Mappïnq

Terrain analysis for the' proposedDempster pipeline

route was based on Es, r.ev;iew of publishe'd geological and geographïcal information and on redpgnition, .and classi- fication of landforms visible on airphôtos.

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A 1and.form is the' most significant recognizable unit that canbe kee.n whe'n vertic41 airpho.tos 'are examined with a stereoscope.' La'ndforms have distinctive topographic and,geomorphïcexpresaion,,,geologic origin and material, drainage and vegetation characteristics. Following iden- tification, ,landformsare mapped as terrain units or terrain types on the basis of their environmerit of deposition. Each terrain unit is the'n described in a legend witha list of characteristic properties.

Terrain mapping not only outlines the boundaries of various terrain unitsbut also fcrrrns a necessary base for use in choosing specific areas where field investigations can provide additional informationfor characterizing terrain units. Field investigations, including., geological and,geophysical surveys and,geotechnical drilling and sampling programs, may then' be 'carried out to determine the geological and engineering properties of .the units,.fox example, material type 'and,ground ice content. Variability of these properties withïn each keirain unitcan also be determined during field studies.

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2.2 Terrain Mz@p'in.g Legend

The legen'd developedfor terrain mapping of this pipeline route 'makes USE ôf letters to symbolize teirain units of different geo'logic origin, specific landformsand erosional features., ,for example:'

peat (veneer) , 1. 3.ov L-R moraine'deposi i" plain rills ,(glacial origin) (land- (erosional form) feature)

When two or mwe terrain units cannot be differentiated at the scale of mapping, they are shown as a complex, for example, Lb.pO, where subscriptsindicate the relative 82 proportion of each.' Where subscripts are absent proportions are approximately equal. Graphic symbols are used to show the location of prominent geologic or man-made features, e,g. 8 / (@SCaKp?Wnt)Or A (borxow pit).

Dominqnt mater'ial, .topography, drainage,and permafrost character'isticsof terrain units, ,as estimated from ai~phdtoe,,geophysicalsurveys, .and a limited number of .. ., drill hole logs;,are 'des'cribedon th& 'terrain legends.

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Soil and bedrock types were identifiedand des- cribed on the basisof published data and thelogs of bore- holes drilled for Foothills Pipe Lines(Yukon) Ltd. during i977 and 1978.

Soil type may vary withinterrain units which had a similar environmentof deposition , due to differences in underlying bedrock, climate, topography, and geologic history. Such regional variations between similar terrain units are accounted,forby means of legends developed for the major physiographic regions crossed by the route. These regions, from north to south, are:

Reqion Number -Name I Mackenzie Delta II Anderson Plain 111 Peel Plain IV Peel Plateau V Richardson Mountains VI Porcupine Plateau VfI Ogilvie Mountains VI11 Tintina Trench IX Yukon Plateau

Topography and drainage have been estimated from airphoto interpretation. The topographic descriptionis based on average slopes occuringwithin a terrain unit, as follows :

-6- Top0.graph.y.I ' 'Slope Angles Terrain Unit . ' ' Exalnp'le'

Depxegsional or flat ta 0-5' Lb undulating Undulating to rolling 5-10' Mm

Hummocky and ridged 5-15a Mh ' Gently to modekatel'y 5-15,' Cb (Pl sloping Moderately to steeply >15* Cm

Drainage, ,as estimated from airphatos, is classified as

The estimates of expected ice contents (unfrozen, low, medium, or high) contained in the terrain legends were arrived at by reviewing the 1977 and 1978 soila logs which include data on ice lens thickness and spacing, NRC ice descriptions, and moisture 'contents. Where logs were unavailable 'ice 'content information has been extrapolated from terrain unite in the 'same area with similar materials and physical settings.

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3 O PHYSIOGRAPHIC:'SETTXNG :

The .Demps.tek pipeline route is located in divisions af the Arctic Coastal Plsin, ,the Xnterior Plains, ,and the Cordilleran physiographic regions .of western Canada. The pipeline route 'and the physiographïc divisions that it croeses are shown on Figure 1 and are categorized from north ta south as follows:

TABLE 1: ' Physiag'r'ap'hic'Eleme'nts

Ma jO'I? Region Physiographic Division Alignment Sheet on' Aiig,nmen't'Sheet Numbers as of December. 1978 Arctic Coasta.1 X- Mackenzie Delta Plain Interiox Plains XI. Andersgn Plain 12,- 13, 13A, 13B, 13C, 13D, 13E(part), 14 III. Peel Plain

m. Peel Plateau 16A, 17, 18 (part) Cordillera Y. Richardson (Eastern Mountains System) VI. Porcupine Plateau 20F, 20G, 21, 22, (E9gle Plain) 22AI 22Bt 22C, 22D, 223, 23, 24, 25, 2 6 (part1 Cordillera VI1 Ogilvie Mountains 26(part) , 27, 27A, (Interior 27B, 27C, 27D, System) 273, 27F, 27G, 27H, 271, 28, 29, 30, 31, 32, 33

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I VITI. Tintina Trench . 33A, 33B, 34, 35, 36, 37, 38, 39, 40 I IX. Yukon Plateau 41, 41A, 41B, 41C, 41D, 42, 43, 44, 45, 46, 47, 48, 48A, 48B, 48Cf 48D, 48Ef I 48F, 48G, 48H, 481, 49, 50 also I 48E-1-6 1 The characteristics of each of the physiographic I elements crossed by the pipeline are described below.

I 3.1- Arctic.. . Coastal. Plain I 3.1.1 Mackenzie Delta I The Mackenzie Delta division of the Arctic Coastal 'I Plain covers that part of the pipeline route from Richards I Island to 4.4 km south of Noel1 Lake and includes the Parsons Lake and Niglintgak laterals. It consists of the I modern Mackenzie Delta and the Pleistocene Delta. The flat- lying modern Mackenzie Delta is a vast deposit of silt and ,I sand that fills the Mackenzie Trough and extends seaward I (Hughes, et al., 1973). It lies a few metres above sea level and is flat and channeled with numerous levees and 1 lakes. I -9- I I HARW ASSOCIATES Cl97EII LTD. I

I The Pleistocene Delta is a complex of older deltic, fluvial, glacial and marine sediments up to 30 m I thick overlying poorly consolidated Tertiary sandstone, I mudstone, and conglomerate. Elevations in the old delta reach 200 m ASL. The Mackenzie Delta division is in the I continuous permafrost zone (Brown, 1967). Thick permafrost and thermokarst lakes and peat-filled depressions are I common. Taliks are encountered beneath major streams. I 3.2 The Interior Plains I The Anderson Plain, Peel Plain and Peel Plateau of 'I the Interior Plains are south.of theArctic Coastal Plain I and east of the Cordillera.

I 3.2.1 Anderson Plain

I The Anderson Plain is the northernmost of these I divisions. It extends along the pipeline corridor from 4.4 km south of Noel1 Lake to the east side of the Mackenzie ,I River. The drift covered Anderson Plain is dissected and undulating. It rises in elevation inland and, along its I southern boundary elevations may reach 300 m ASL (Hughes, et 1 al., 1973). However, along the pipeline corridor elevations range from 30 to 150 rn ASL. I - 10 - I I , HARm ASSOCIATES Cl9781 LTD. I

I The easternpart of the Anderson Plain (eastof 13O03O1WLong) is underlainby Middle Devonian limestoneand I shale with some plateau summit areascapped by Cretaceous I sandstone and shale. The western part is underlain by Upper Devonian sandstone and shale. The Anderson Plain is inthe I continuous permafrost zone and has thick permafrost, thermo- karst lakes andpeat-filled depressions. Taliks are encoun- I tered beneath major stream channels. I 3.2.2 Peel Plain I Peel Plain liesbetween the Mackenzie and Peel I Rivers and is bounded on the north by the Mackenzie Delta I and in the south by Peel Plateau, Mackenzie Plain and the Franklin Mountains. Peel Plain is a flat-lying and poorly I drained glaciated plainwith two localizedareas of greater relief, the Grandview Hills anda moraine belt between I Arctic Red River and Fort McPherson. Along the pipeline I route elevations are in theorder of 30-60 m ASL, but in Grandview Hills, southof the pipeline, elevationscan reach I 300 to 450 m ASL. The southern and central parts of Peel Plain are underlain by flat-lyingLower Cretaceous shale and I minor sandstone. In the north flat-lying Devonian shale and I sandstone are present. In the vicinity of the pipeline I I - 11 - HARDY ASSOCIATES ClS78l LTD.

route Peel Plain lies within the continuous permafrostzone and has fairly thick permafrost,-peat-filled depressions, and thermokarstlakes.

3.2.3 Peel Plateau

Peel Plateau is south and west of Peel Plain and east of the Richardson and Mackenzie Mountains. It rises in steps from Peel Plainto the mountains. The southeastern part of Peel Plateau, whichis adjacent to theMackenzie Mountains, consistsof broad mesa-likeuplands which are developed on resistant Cretaceous sandstone(Hughes, et al., 1973). The pipeline crosses the northernand western part of Peel Plateau which, preglacially, wasa rather uniformly sloping piedmont slope developedon shale and sandstone. Ice from the east deposited till on allof the Peel Plateau during the Pleistocene, In postglacial times it was dissected by meltwater channelsand by streams which have incised their courses to considerable depth(up to 300 m) . The Peel Plateau lies within the continuous permafrostzone and in the northern part of the "widespread" discontinuous permafrost zone. Drill holes and geophysical data indicate that most surficial materialsare frozen.

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3.3 Cordillera (Eastern System)

The Richardson Mountains and the Porcupine Plateau are the two divisions of the eastern Cordillera that are crossed by the pipeline corridor.

3.3 .1 Richardson Mountains

Thb Richardson Mountains are adjacent to Peel Plateau and begin about 40 km west of Peel River. Their western boundary along the corridor is situated appraxixately 20 km north of the Eagle River. The northern and southern Richardsons have slightly different physiographic and geologic characteristics. North of latitude 67' the mountains are more rugged with several peaks to 1525 m ASL- Sandstone, shale, conglomerate, and carbonate rock of Paleozoic and Mesozoic age form this structurally complicated part of the mountains. South of latitude 67' the Richardsons are developed on a broad, faulted anticline with relatively resistant carbonate, chert and argillite of the Road River Formation on the east and west flanks and a central core of siltstone and mudstone. Elevations in this part of the mountains are at 1220 m ASL. Several low points, e.g. MacDougall Pass, along the Richardson Mountains were glaciated

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I by tongues of ice from the east. The part.of theRichardson Mountains crossed by the pipeline route lies within the I "widespread" discontinuous permafrost zone. Drill hole logs I I I 3.3.2 Porcupine Plateau I The Porcupine Plateau begins at the western edge of Richardson Mountains approximately 20 km north of the I Eagle River and extends southward toward the Taiga and Ogilvie Ranges. The southern boundary of the Porcupine I Plateau has been placed at Churchward Hill near the Ogilvie 'I River. However, it should be noted that between Churchward Hill and Chapman Lake inliers of both the Mackenzie Mountains I (Taiga Ranges) and the Porcupine Plateau are also present 1 within the Ogilvie Mountains region. Included in the Porcupine Plateau areunglaciated plains, uplands, and I mountains which are quite diverse. The pipeline corridor is situated mostly in the southern portion of the Porcupine I Plateau known as the Eagle Plain. The Eagle Plain is a I broadly dissected unglaciated plain developed on flat-lying or gently deformed sandstone and shale of Mesozoic age. In I this area long even-topped ridges have broad, gently rounded summits. Elevations reach 760 m ASL on some ridges. I I - 14 - I HARDV ASSOCIATES 119781 LTD. I I At lower elevations throughout Eagle Plain nonglacial alluvial deposits fill valleys and colluvial deposits I blanket slopes. The Porcupine Plateau lies within the "widespread" discontinuous permafrost zone. Most subsurface I data indicate that surficial materials are frozen throughout I this area.

I 3.4 Cordillera (Interior System)

I 3.4.1 Ogilvie Mountains I The Ogilvie Mountains physiographic division 'I begins at the south end of the Porcupine Plateau (Eagle Plain) and extends southward to the Tintina Trench. This 'I division has two parts (1) the northern area which includes I Central Ogilvie Ranges, Taiga Ranges, Ogilvie Valley, and Taiga Valley, and (2) the southern area or Southern Ogilvie I Ranges. The northern area extends from Porcupine Plateau to a point about 16 km south of Chapman Lake and consists of I sedimentary and metamorphic strata of Paleozoic and Precambrian I age. Plateaux with elevations near 900 m ASL are underlain by less resistant formations and mountains with elevations - " _" .. "" I of 1500 m ASL by more resistant units. Some of this area I was glaciated during the Pleistocene by valley glaciers.

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The southern area of the Ogilvies begins about 16 km south of Chapman Lake and consists of a belt of metamorphic and igneous rock. Large streams flow normal to this belt of mountains and cut it into segments. The mountains have a rugged appearance and consist of long branching ridges connecting jagged peaks. Elevations on the peaks range from 1525 rn to 2130 rn ASL and in the river valleys elevations are approximately 760 m ASL. Pleistocene valley glaciers existed in the interior of these ranges. However, they did not extend beyond the southern borders of the mountains and decreased in extent and number to the west (Bostock, 1948). Cirques are located in the Ogilvies, but they have no existing glaciers. The Ogilvie Mountains are 'I within the "widespread" discontinuous permafrost zone. North of North Fork Pass drill holes and geophysical surveys indicate permafrost is found in most deposits. South of North Fork Pass permafrost is still comon especially in fine grained deposits and on north facing slopes, but some unfrozen drill holes were present.

3.4.2 Tintina Trench

Tintina Trench physiographic division lies south- west of the Ogilvie Mountains. It is bounded on the north- east and south by subdivisions of the Yukon Plateau. The

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Tintina Trench is a broad valley feature comparableto the Rocky Mountain Trench. It extends from near longitude 130° northwest across longitude 141O into Alaska, The pipeline corridor crosses thisregion between Benson Creek eastof Dawson and Stewart Crossing southwestof Mayo, The Tintina Trench has straight walledsides and accordant floor levels with elevations from 425 m to 820 m ASL. The trench is a zone of intense fracturing, faulting, and shearing with the geology on either side being dissimilar (Bostock,1963). In the mountain ridgeson the northeast side metamorphic phyllite, quartzite, marble, slate, and paragneissof Precambrian and Paleozoic age predominate. Some Mesozoic intrusive ,granites are alsopresent. Southwest of Stewart River, in the trenchfloor and in the first hills of the upland, Mesozoic intrusivesincluding granites and volcanics predominate. Further southwest into the hills Precambrian schists, gneisses and quartzites are present.

The trench itselfis floored by broad terraces of Tertiary gravels and Pleistocene drift in which larger creeks are entrenched, exposing outcrops in thebases of their cutbanks (BostÔck, 1948) The trench was glaciated at least twiceby. coalescing valley glaciersin early Pleistocene time and drift from the later of these two glaciations is at ground surface. The Tintina Trench lies within the "widespread"

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discontinuous permafrost zone. Drill holes and geophysical surveys indicate that permafrost is present in areas with thick organic cover or fine grained deposits. Coarse grained deposits without surface cover Of organic 01 eolian material are often unfrozen.

3.4.3 Yukon Plateau

The Yukon Plateau division lies both northeast and southwest of the Tintina Trench. The pipeline enters the Yukon Plateau southwest of Tintina Trench near Stewart that slope and diminish in size northward. Elevations in this area range from 750 to 1370 m ASL. Northern Lewes Plateau is underlain by Precambrian metamorphic rock on the northeast and a belt of Mesozoic rock on the southwest. Both rock typeshave been intruded by granite plutons and contain some small bodies of Tertiary volcanics.

The southern part of Lewes Plateau consists of a broad, irregular depression underlain by relatively non- resistant, folded Mesozoic sediments flanked by tougher Mesozoic volcanics that form Semenoff Hills on the northeast and Miners Range on the southwest. In this Part of Lewes

Plateau the upland surface is'raflected in the accordance of summit levels. The average elevation 1060 m to 1220 m ASL, about 150 m lower than the surrounding plateau area.

Several areas northeast of Carmacks and in Miners Range appear to have escaped glaciation in Pleistocene time, but elsewhere Lewes Plateau was completely covered by ice. The Lewes Plateau portion of Yukon Plateau lies within the "southern fringe" of the discontinuous permafrost zone. Permafrost is found at some localities but it is generally 'I sporadic in occurrence and is usally fairly thin. It is most often found in areas with thick eolian silt or organic cover and on north-facing slopes.

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I 4.0 GEOLOGIC HISTORY I 4.1 Bedrock Geoloqy I 4.1.1 Arctic Coasta,1 Plain,Interior Plains I and Cordillera (Eastern System)

I Bedrock along the routeis varied and ranges in age from Precambrian to Tertiary. In the ArcticCoastal I plain (Mackenzie Delta), Interior Plains (Mackenzie Delta, I anderson Plain, Peel Plain, and Peel Plateau) I and Eastern Cordillera (Richardson Mountains and Porcupine Plateau), the .I bedrock consists of Paleozoic, Mesozoic, and Tertiary sedimentary formations. Sediments deposited in shallow I marine, continental, and marginal marine environments formed I these rocks which include limestone, mudstone, siltstone, shale, sandstone, argillite, conglomerate, chert, limestone, I and dolomite. In the ArcticCoastal Plain and Interior Plains most of the area has remained undisturbed or has I experienced only minor folding, faulting, and uplift. ,I However, in the Richardson Mountains and Porcupine Plateau the formations mentioned above and older strata have been I uplifted during periods of crustal movement to form the I Richardson Mountains and the hills of Porcupine Plateau.

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I 4.2.2 Cordillera (Interior System) I The Interior System of the Cordillera (Ogilvie I Mountains, Tintina Trench, Yukon Plateau) includes folded and faulted sedimentary and volcanic strata, massive : I metamorphic rock, small and large bodies of igneous intru- 1 sives, and local areas of flat-lying volcanics.

I Ogilvie Mountains

I The northern part of the Ogilvie Mountains I consists of sedimentary and metamorphic formations of Precambrian, Paleozoic, and Mesozoic ages. Sedimentary I rocks include limestone, dolomite, chert, conglomerate, sandstone, shale and argillite. Precambrian sedimentary I rocks, e.g. argillite and limestone, were derived from well- I sorted arenaceous and argillaceous sediments and dolomite- rich arenaceous sediments, which were eroded and deposited I during the Precambrian and deformed during the Racklm Orogeny shortly after their deposition. Structures produced ,I during this orogeny range from block faults through open I folds to complex folds (Green, 1972).

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From the. Late 'Precambrian to. nextthe major orogeny in Cr.etaceo.us.time (Laramide Orogeny) , ,poorly sor.ted clastic sedimentary,units,, che'rt, limestoneand dolomite were deposited. The Laramide Orogeny deformed these Paleozoic and Me.sozoic units 'as well as the underlying Precambrian formations. Deformationwas not as strong in the northern Ogilvies'as in the southern belt and areasof relatively open foldsseparate structurally complex areas.

In the southern Ogilvies (beginning approximately 16 km south of Chapman Lake) sedimentary unitsinclude chert, shale, argillite, and canglomerate withminor lime- stone and dolomite which were.depositedin Precambrian, Paleozoic and Mesozoic time.

During the late Frecambrian and earlyPaleozoic, volcanic activity resultedin deposition of tuff, volcanic breccia, agglomerate,,. ,and andesite inthis part of the Ogilvies. Xn early Mesozoic time more 'shale andlimestone were deposited and in theëcretaceous dioriteand gabbro sills were intruded intothe'ss sediments prior to themajor period of deformqtion. The' Laramide Orogenywas strongest in the southe'rn Ogilvies' resultingin the formation of complex folds, .and intrusion of granitic stocks. Met'a-

., morphic units, including quartzite, schist,and phyllite,

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I were formed at this time from sedimentary units that were I folded, faulted and intruded.

I Tintina Trench

I Tintina Trench is filled with a thick sequence of I Tertiary gravels and Pleistocene glacial deposits. Bedrock structures related to formation of the trench arepresent I along its northeast side. Some bedrock (Mesozoic granite and volcanic rock) occur near the surface in the trench I southwest of Stewart Rivez. These formations also form the principal element in the upland south of the trench (Bostock, 1963) . Further south in these hills Precambrian metamorphic schist, gneiss, and quartzite predominate. Some of these metamorphic rocks are of Paleozoic age and there is no evidence of an earlier period of orogenic activity predating them or of the presence of a crystalline basement (Green, 1972). The metamorphic rocks have been intruded by Mesozoic

granite which has produced granite-gneiss. A string of ultrabasic intrusions also lies in a belt parallel to and southwest of Tintina Trench. After Mesozoic intrusive activity, volcanics and associated sedimentary rocks were deposited at scattered localities. These units have been subsequently folded or tilted after the main period of deformation. Still later, planation, tilting, and deep weathering occurred.

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I Northeast of Tintina Trench, uplands consisting I of metamorphic phyllite, quarzite, marble, slate and para- gneiss of Precambrian and Paleozoic ages occur. There is no I direct correlation with rock units southwest of the trench; however, some units have certain similarities. Units to the I southwest have higher metamorphic rank than those to the I northeast. I Yukon Plateau

I The southwestern Yukon Plateau (Lewes Plateau ,I division), which is crossed by the pipeline corridor south of Tintina Trench, is underlain by Precambrian metamorphic *I rocks including schist, quartzite, and phyllite which are overlain in some localities, particularly south of Minto, by I Mesozoic clastics and carbonates. Granitic intrusions of I Mesozoic age and Tertiary volcanics and clastic sedimentary formations are also present. I In the northern section of the Lewes Plateau, I schist, quartzite, and phyllite of the Yukon River Group I represent metamorphosed sediments and volcanics which have been intruded by granite plutons in Precambrian and early Paleozoic time. Mesozoic granites and granodiorites were

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I also emplaced in thes'e'rocks:during the Laramide Orogeny. I Precambr,ian fomatians and Mesozcric intrusives occur at the surface along the pipeline 'corridor from south 'of Stewart I Crossing to Minto.

I Mesozc?ic conglomegste, ,sandstone, ,shale, coal, I arkose, and tuff of thê Tantalus,and Laberge Series overlie Precambrian metamorphïc units between Minto and Carmacks. I Mesozoic granitic intrusives are also present.

I The southern section of Lewes Plateau begins near I Carmacks and extends southward to Whitehorse. In this area, Mesozoic clastic and volcanic.rocks including the Laberge *I Series (conglomerate, sandstone, shale, tuff, coal), the Tantalus Formation (conglomerate, .sandstone, shale, coal) , I the Lewes River Group (sandstone, argillite), Mt Nassen 1 Volcanics (basalt, andes'ite, ,dacite, breccia, and tuff) , Hutshi Group Volcsnics (andesite, basalt, breccia, and tuff) I and Tertiary volcanics of the Carmacks Formation predominate. Some Mesozoic granite intrusives occur in this portion of I the corridor just north 'of Whitehôrse. I 1 I - 25 - I I I

I 4.2 Quaternary Geology I The portion of the Northwest Territories and the I Yukon that is crossed by the Dempster pipeline corridor has since I had a diverse history Tertiary time. I 4.2.1 Arctic Coastal Plain and Interior Plains

I The Arctic Coastal Plain (Mackenzie Delta), Interior Plains (Anderson Plain, Peel Plain, Peel Plateau) I and MacDougall Pass in the Richardson Mountains underwent I erosion from Tertiary until Quaternary time and were glaciated at least twice during the Pleistocene epoch by .I continental or Laurentide ice-sheets moving from the south and east. Drift associated with the last glacial advance I and retreat is commonly at ground surface throughout these I areas. Drift includes all rock and soil material deposited directly from glacier ice and all types of materials deposited I by water associated with themelting of glacier ice-sheets. Till derived directly from glacier ice and deposited in I morainal landforms is the major type of drift which covers I bedrock throughout the Arctic Coastal Plain and Interior Plains physiographic regions. Stratified drift including I ice contact stratified drift (eskers, kames, kame terraces), I proglacial sediments (glaciofluvial plains and terraces, I - 26 - I I I glaciolacustrine, anddeltaic plains), and.glaciomarine materials have been deposited from water associated with I melting of the Laurentide ice-sheet. The ice-contact I stratified drift deposits commonly overlie deposits till and are scattered throughout the area. Proglacial deposits I including glaciofluvial, deltaic, and glaciomarine materials are found mostly near the Beaufor4 Sea in the Mackenzie I Delta division of the Arctic Coastal Plain and glaciolacustrine I deposits are found at some isolated localities overlying till deposits in the Anderson Plain. I Laurentide ice moved generally northwestward across the Arctic Coastal Plain and Interior Plains during the last Wisconsin glaciation. However, during its retreat the development of minor lobations controlled by low relief features in the Mackenzielowlands produced a complicated pattern of ice-flow features (Hughes, 1972). Major halts or readvances are inferred from moraineslike the one near Fort McPherson. In these ridged andhummocky moraine landforms, drift can be up to 30 m thick. However, in large areas of Anderson Plain, Peel Plain, and Peel Plateau morainal deposits can be less than 2 m thick.

- 27 - I HARW ASSOCIATES Cl8781 LTD. I I

I After the glacial retreat and draining of glacial lakes, weathering processes continued to erode bedrock and I soil materials. Alluvial plains and terraces formed along I rivers and streams, and deltaic sedimentation continued along the mouth of the Mackenzie River. Water erosion and I mass wasting resulted in the formation of colluvial deposits along river and stream valleys. Topogyaphic lows were the I site of deposition of fine grained sediments from slopewash and small streams. Organic deposits also accumulated in these low areas. Permafrost formed in surficial materials and in some areas where permafrost had thawed thermokarst features developed.

4.2.2 Cordillera (Eastern System)

The Eastern System of the Cordillera includihg Richardson Mountains and southern Porcupine Plateau have undergone erosion and weathering from the Teritary until the present. NO Cordilleran or Laurentide ice-sheets covered the area except for a tongue of Laurentide ice which entered MacDougall Pass from the east. Also peaks south of MacDougall Pass with elevations of 1525 m supported restricted cirque glaciers. Because Richardson Mountains and southern Porcupine Platelu were not glaciated, the character of local terrain

- 28 - HARDV ASSOCIATES ClB781 LTD.

is determined mainly by the .lithology and .structure of subjacent bedrock.. Mo:untain slopes are mo,stly co.vered with detritus ranging from silty gravel to coarse 'blQcky debris which ap.pears to. have. little 'segregated ice. Lower slopes are mantled by finer slopewash 'sedimen'tswith high ice contents. Alluvial plains and terraces' consisting of sands I and.gravels are 'found alongmountain va1.ley streams. In the southern.Porcupine Plateau (Eagle Plain) sediments and low hills rise toward high hills and mountains. I The low hills and sediments are developed mainly on sand- stones, carbonates, ,siltstones and shales. Pediments are .I mantled by 1 to 2 m of silty, ,poorly sorted gravel overlain I by 1 to 2 m of organic silt which is generally ice-rich. The low hills typically have a thin mantle .of Stoney silt to I silty gravel (1.to2 m thick) with local accumulations of ice-rich slopewash silts (1 to 10 rn thick) on,gently slopes I and valley bottoms. The relationships of pediments to

modern rives's suggests.. that erosion kept pace with local upwarping that may have begun during or just after pediment development (Hughes, 1972).

- 29 - I HARDY ASSOCIATES lIB78l LTD. ~Ii i I Permafrost has :fo'rmed in col.l.uvia1and alluvial deposits. throughout the Ri.chardson Mountains and southern 1 Porcupine Plateau. Organic deposits have also accumulated 1 in areas wher'e 'fine .grained'mates'ials 'are present, ,e.g. lower slopes on pediment surfaces ,and alluvial deposits along river's. I 4.2 ..3 Cordillera (Interior System) I The Interior System of Cordillera including the Ogilvie Mountains, .Tintina Trench, and Yukon Plateau had related yet slightly different histories during the Quaternary. All three divisions have been glaciated.

Ogilvie Mountains

Valley glaciation occurred in the Ogilvies and evidence for this is best displayed in the vicinity of the headwaters of Ogilvie River where at least three glacial advances have been recorded (Hughes, .1972). Deposits left by these advsnces include:

- 30 - HARDY ASSOCIATES t’lB781 LTD.

b) moraines that are subdued but still recognizable (intermediate glaciation)

c) patches of till with little or no characteristic moraine form (old glaciation)

Ricker in detailed mapping of the North Klondike and East Blackstone Valleys alsoinferred two advances from moraines in the vicinity of Chapman Lake (Hughes, et. al,1972). I‘ Each successive glacial advance was less extensivethan the previous one.

Morainal deposits associated with the valley glaciation described abovebegin along the pipeline route near Chapman Lake and are comon as far south Northas Fork Pass. These deposits include undifferentiated morainal materials, ablation moraine, hummockymoraine, rolling moraine, ridged moraine, and moraine veneer deposits.Some glaciofluvial and scattered glaciolacustrine deposits are also associated with these morainal materials. Postglacial windblown silt and organic deposits overlie morainaland glaciofluvial materials throughout the area. Permafrost is present in almost all glacialand nonglacial surficial materials throughout thenorthern Ogilvies.

- 31 -

...... CEb HARW ASSOCIATES ClB78l LTD.

From Nor.th Fork 'Pass southward to the beginningof Tintina Trench,scattered morainal and glaciofluvial deposits related to a piedmont glacierthat occupied North Klondike Valley. are 'found along .the valleywalls. However, along this section of th&, route the most common materialsinclude postglacial alluvial plaindeposits. of the North Klondike River and alluvial fanand colluvial deEjosits which originated in the mountains adjacent to the North Klondike Valley. Varying thicknesses of postglacial windblown silt cover these deposits and organic materials are found insome areas. Permafrost is found in most deposits throughout this section, but some unfrozen coarse materials are alsopresent.

Xn the Ogilvie Mountains northof Chapman Lake, the most prominent materials along the pipelineare sediment- ary rock, thin and thick colluvium on pediment slopes, and alluvial plain, fanand terrace deposits. Glacial deposits seem to be absent from this portion of the Ogilvies. PeT'mafrost is found in most surficial deposits.

Tintina Trench

Tintina Txenchand the Stewart River Valley are filled with thick glacial deposits (up to 180m), which representseveral advances ofthe Cordilleran ice-sheet during Pleistocene,the

- 32 - HARW ASSOCIATES tlB781 LTD.

The youngest glacial materialswere deposited during the McConnell Glaciation.The youngest of the older drift units, the Reid, extends westward down Stewart Valley about 64 km beyond the McConnell limitand displays glacial features including an end mazaine(Reid end moraine). West of this moraine in lower Stewart Valley, glacial landforms are not visible but grey siltyto clayey till and erraticsof the older Klaza Glaciationare present. The Klaza Glaciation extended at least 40 km beyond the Reid limit and in lower Stewart Valley the oldest glacier(the Nansen) extended 40 km beyond the Klaza. This oldest glaciation is represented by thick hummocky drift which is extensively weathered

Thick glacial deposits near the Klondike River in Tintina Trench include 90 m of glaciolacustrine sediments overlain by 120 m of glaciolacustrine or morainaldeposits which is overlain by a surface deposit of gravels. These surface gravelsare from a Pre-Reid or Prs-Wisconsin glacia- tion and are overlainby a thin coverof loess of McConnell age (Hughes, et. al., 1972). These materials near the Klondike River originatedfrom piedmont glaciers in the North Klondike and Klondike Valleys. Similar surficial gravels and silts are foundalong the pipeline corridor

- 33 - HARDV ASSOCIAYES t18781 LTD.

between Klondike River and a point north of McQuesten River. In this area organic deposits have accumulated where thick loess deposits and poor drainage are present. Alluvial deposits have formed along steams and colluvium has accumu- lated on valley walls. Permafrost exists throughout this area in localities with thick loess and organic cover.

Just north of McQuesten River, outwash material from the Reid Glaciation is present in a terrace. Loess which mantles the terrace surface is of McConnell age. From McQuesten River to Stewart Crossing, traces of McConnell age outwash and older glacial deposits lie along the route. Post-glacial alluvial plains arid terraces of Stewart River are also prominent. In .some poorly drained portions of the terraces, organic deposits have accumulated. Permafrost is present beneath these organic deposits and in areas with I thick loess. I Yukon Plateau

I The Yukon Plateau begins just south of Stewart I Crossing and extends southward to Whitehorse. The pipeline crosses drift of Reid age between Stewart Crossing and I Minto. This drift includes moraine veneer, moraine Plain, I hummocky and rolling moraine deposits, glaciofluvial plain I - 34 - II 44 ASSOCIATES CIS781 LTD. I

I materials, and some glaciolacustrine deposits. Organic I deposits have formed in low-lyingareas and eolian dunes were created from glaciolacustrine materialsin at least one I locality. Permafrost is found where organic deposits are thick and beneath thick fine grained eoliansilts or glacio- I lacustrine silts and sands. Colluvial deposits haveformed I on slopes and alluvial deposits have developed adjacent to major rivers like the Pelly.

From Minto southwardto Whitehorse the pipeline I crosses drift of McConnellage. The entire area, except for I highlands like Miners Range, was covered by ice during the McConnell or Wisconsin Glaciation. In some localities loess and White River ash cover glacial deposits. These deposits include extensive glaciofluvialhummocky, rolling, plain and terrace deposits, moraineveneer and plain deposits, and glaciolacustrine materials.

Colluvial deposits have formed bedrock on and on valley walls. Alluvial plains and terraces are present along rivers. Organic deposits have accumulated in low- lying areas. Permafrost is confined to north-facing slopes and localities where fine grained materialsor organic deposits are present.

- 35 - HARDY ASSOCIATES CIS781 LTD.

Soil types and other geologic characteristicsmay vary within terrain units whichhad a similar environmentof deposition becauseof differences in underlying bedrock, climate, topography, and geologic history. For example,a moraine plain atthe northern end of the route (Anderson Plain) will consistof silty clay till while thesame unit at the southern end (Tintina Trench) will containgravelly sandy till. Both units were deposited by glacier ice but the northern moraine plain originated as the late Wisconsin Laurentide ice-sheeteroded and redeposited earlier glacial I 'I deposits and sandstone and shale. The southern moraine plain depositsin Tintina Trench were depositedby Cordilleran I ice during,a pre-Wisconsin glaciation. This glacier eroded I and depositedearlier glacial depositsas well as igneous and metamorphic rock. I The variationof soil types andother geologic I characteristics of terrain units canbe seen on Tables 1-9 I which follow. Terrain units on thesetables are grouped by physiographic region accordingto their geologic origin with I the most recently deposited unit listed first.

I - 36,- Map Terrain Type Landform Characteristics Surface Drainage Engineering Drainage SurfaceCharacteristics Landform Type Terrain Map Symbol Soil DescriptionIceThicknessesGround Topography GroundwaterConsiderations and Slope

Active Stratified silt, sand Flat Unfrozen <3O Fairdrainage, some Frequently Floodplain gravel standingwaterinundated

Inactive Stratified silt, - can <3O Good Ap2 Unfrozen Flat drainagePeriodically Floodplain sand, gravel be frozen under inundated organic cover

At Alluvial Stratified sand and UsuallyFlat to gently <3O Good drainagePossible source of Terrace gravel, silt veneer unfrozen,low undualting, steep except borrow. granular icecontent frontal scarps for scarps where frozen

Av Alluvial Stratified silt,sand Unfrozen Flatundulating to <3O Good drainage Veneer and gravel

Lb Lacustrine Stratified silt and Patches of Flattodepressional <3O Poorly drained,some Buoyancy controls Bas in clay, minor sand and permafrost where ’ standing water required where organics present they are extensive ice-rich

LP Glacio- Stratified silt and Permafrost Flat to verygently <3* Poor drainage water, Buoyancy controls lacustrine clay, minor sand, where present undulating, thermokarst in depressions may be required Plain organics in depressions is highice depressions Frozen areas should content be avoided due to thaw settlement potential TABLE 1: PHYSIOGRAPHIC REGION I - MACKENZIE 3LTA

(Alignment Sheets 1-11,9 at 9bl

Terrain Type Characteristics Landform SurfaceDrainage Engineering Symbol Topograph:Soil Ice Description ThicknessesGround GroundwaterSlopeand Considerations

€0 Fen Featorganicand silt Unfrozen; small Flat to depress. lal’ <3O Poor drainage, Buoyancy control areas of high standing water, required if ice extensive

Po Bog Peat High Flat to depress. Poor drainage, ~uoyancycontrol standing water may be required if extensive pov Bog Veneer Peat <2 m High - Level to depres. mal <3O Poor drainage, Buoyancy control may reflect und1 lying standing water may be required material locall’ locally cm co 1 luvial Colluvium predominantly Low to medium Gently to steep Fair to good Slopewashsilt and sand;gravel sloping drainage locally

Ad Alluvial Stratified silt, clay Medium to high Flat to undulat Generally good with Buoyancy control Delta and sand, minor channelled high water table, and deep burial organics poor in channels may be required i AP Alluvial Stratified silt, sand Medium to high ; Flat to gently <3O Good drainage Buoyancy control Floodplain and gravel, silt locally unfrozen undulating, channelled generally, high and deep burial .dominant in Delta area water table,poor in may be required t channels I TABLE 1: PHYSIOGRAPHIC REGION I - MACKENZIE DELTA

Terrain Type Engineering Drainage LandformSurface Characteristics Soil DescriptionThicknessesTopography IceGroundSlope and GroundwaterConsiderations

Stratified silt, ~awto medium Flat; steep frontal <3O Good drainage Potential source At Alluvial sand, I Terrace and gravel, silt scarps except in of granular borrow veneer scarps 1i 1, Lacustrine Stratified silt and High Flat to depressi@al <3O drainage,Poor Buoyancy control Bas in clay, minor sand and standing water may be required 1 frequent organics i LP Glacio- Stratified siltand High Flat to gently <30 Poor drainage, Buoyancy control lacustrine clay, some sand, undulating standing water in may be required Plain organics in depressions depressions locally I j- LV Lacustrine Stratified siltand <2 rn High Topography is a <3°t050 Poor drainage, Veneer clay, some sand and reflection of un A

UP Terrain Type CharacteristicsLandform I SurfaceEngineering Drainage Symbol Soil DescriptionThicknessesGroundwaterTopography and IceGroundSlope Considerations

Gt Glacio- Stratified sand and Low (some ice Undulating,with steep <3O up to Good drainage Potential source fluvial gravel, frequent silt wedges ) scarpfrontal 30° on of granular borrow Terrace veneer scarps

Md Drumlinoid Silty clay till Low on ridges, Flat to undulating, Up to 15' Good drainage Moraine high between occasional elongLte Plain ridges steep-sided ridges

Mh Hunrmocky Silty clay till.; sand Medium to high Hummocky 9O to:.15* Generally good Moraine and gravel lenses, surface drainage, organics in depressions poor in depressions

Mm Rolling Silty clay till; Medium to high Undulating to rolling Up to 9* Good, high water Moraine organic veneer in table in depressions depressions

MP Moraine Silty clay till Low to high; Flat to undulting 3* to 9O Fair to good drainage Plain ' mostly medium

Mv Moraine Silty clay till €2 m Low to high; Topography reflebts Up to 20° Good drainage, high Ease of excavation Veneer mostly medium that,of underlyqg water table in depends on depth mate rial depressions material to bedrock and j bedrock type 1 TABLE 1: PHYSIOGRAPHIC REGION I - MACKENZIE DELTA

Terrain Type Engineering Drainage LandformSurface Characteristics Soil DescriptionThicknesses IceGround Topography Slope and GroundwaterConsiderations

IRNone Bedrock drainage Good to low Excavation may be (ss) ------Sandstone & conglomerate difficult t

I

I TABLE 2: PHYSIOGRAPHIC REGION II - ANDERSON PL?'LIN

(Alignment Sheets 12,13, 13A - 13E (part))

Type Landform Characteristics Surface Drainage Engineering Drainage SurfaceCharacteristics *PLandform Terrain Type Symbol Soil DescriptionThicknessesGround Ice Topography SlopeGroundwater Considerations and

Fen Peat and organic silt Unfrozen; local Flat to depressional Poor drainage, Buoyancy control areas frozen standing water may be required with high ice content

Fen Veneer Feat and organic silt <2 m Unfrozen Flat to depressional Pmr drainage Buoyancy control may be required

Bog Peat High Flat to depressional Poor drainage, Buoyancy control standing water may be required

Bog Veneer Feat <2 m High Flat to depressional Poor drainage, Buoyancy control standing water may be required locally

Colluvial Colluvium, predominantly Lower to medium Gently to steeply Fair to god Slopewash silt and sand sloping drainage

Colluvial Gravity-transported <2 m Medium to high Reflection of Fair to good Veneer mixture of clay to underlying material, drainage gravel sizes; mostly often bedrock

Alluvial Stratified sand and Medium to high, Flat gently undulating, <3O Good surface Buoyancy control Floodplain gravel, minor silt locally channelled drainage, high water and deep burial unfrozen table may be required TABLE 2: PHYSIOGRAPHIC REGION II - ANDERSON PLAIN

Terrain Type' Landform Characteristic!S Engineering Drainage Surface Symbol Soil DescriptionThicknesses Ground Ice GroundwaterConsiderations TopographyandSlope

Active Stratified silt, sand, Unfrozen; may Flat Poor drainage; open Frequently in- *Pl Floodplain and gravel be frozen water undated; deep burial may be required

Inactive Stratified silt, sand Medium to high Flat Poor drainage Periodically Ap2 Floodplain and gravel inundated

At Alluvial Stratified silt, sand Low to medium Flat . Good drainage Potential source Terrace and gravel; silt veneer of granular material

Lb Lacustrine Stratified siltand clay High Flat to depressional Poor drainage, Buoyancy controls Bas in minor sand, frequently standing water may be required organic-rich

LP Glacio- Stratified silt and High Flat to gently Poor drainage, Buoyancy controls lacustrine clay, some sand, undulating standing waterin , may be required plain organics in depressions depressions locally

LV Lacustrine Stratified siltand <2 m High Flat, some reflection Poor drainage Veneer clay, some sand and of underlying deposit standing water, in organics depressions TABLE 2: PHYSIOGRAPHIC REGION II - ANDERSON PLAIN

Ter rain Type-P Terrain Engineering DrainageLandform Surface Characteristics Symbol DescriptionSoil Thicknesses TopographyGroundIce Slope and GroundwaterConsiderations

Gm Eskers Stratified sandand Low (locally Steep-sided sinuous Up to 30' Good drainagePotential source gravel, minor silt high 1 ridges of granular borrow

Gt Glacio- Stratified sand and LOW Flat ot undulating, <3O up to Gooddrainage Potential source fluvial gravel, silt veneer steep frontal scarp 30° on ofborrow granular Terrace scarps

M Moraine Silty clay till Variable Masked by other j Variable Undifferent- deposits f iated + I Md Drumlinoid Silty clay till Low on ridges; Flat to undulating. 9O to 15O Good drainage Moraine withridgeshighin depressions

Mh Hummocky Silty claytill with Medium to high; Rolling to hummocky 9O to lSo Good drainage, poor Moraine organics in depressions; high in in depressions gravel levels depressions

Mm Rolling Silty clay till with Medium to high Undulating to rolltng 3O to 9O Good; high water Moraine organics in depressions 1 table in depressions

i TABLE 2: PHYSIOGRAPHIC REGION II - ANDERSON PLAIN 1 'i

Map Terrain TypeEngineering Drainage SurfaceCharacteristics Landform Symbol DescriptionThicknesses Soil Ground Ice Topograp SlopeGroundwater Considerations and

1' Mp Moraine Siltyclaytill Low to high; Flatgently to 3O to 9O Fair to good Plain drainageundulating medium mostly

Mv Moraine Silty clay till <2 m Low to high; Topography Up to 20° Good drainage, high Ease of excavation Veneer mostly medium water tablein depends on depthto bedrock depressions underlying rock and rock type

R (Bedrock) s Sedimentary rock Undulating to rolv VariableFair to good May be rippedif undifferentiated mostly soft shale

R sm Siltstone, mudstone, Undulating to rol VariableFair to good May be ripped if shale, argillite softer rock predominates R ss Sandstone and VariableFair to good Excavationmay conglomerate requrie blasting t

TABLE 3: PHYSIOGRAPHIC REGION III - PEEL @IN

Type Landform Characteristics Surface Drainage Engineering Drainage SurfaceCharacteristics -PLandform Terrain Type Symbol Soil DescriptionThicknesses GroundwaterConsiderations and Slope GroundTopograp Ice

Fen. Peat and organic silt Unfrozen; small Flat to depressional <3* Poor drainage,Buoyancy control areas with high standingwater may be required ice

Fen veneer Peat and organic silt <2 rn Unfrozen Flat to depressional <30 drainage,Poor Buoyancy control t standingwater may be required

Peat High Flatdepresswnal to <30 Poor drainage,Buoyancy control 1 Standingwater may berequired i Bog Veneer Peat <2 rn High Flat to depressipnal <3* Poor drainage,Buoyancy control I- standingwater maybe required 1 Colluvial Colluvium, predominantly Low to medium Gently to steep 3Oto>15* Fair to good drainage Slopewash silt, and sand sloping

Alluvial Stratified silt, sand, Medium to high; Flat to undulat' g; e30 Surficially well Buoyancy control

Floodplain and gravel Locallyunfrozen channelled I. drained, high water and deepburial table may be required 1 z'i' Active Stratified silt, sand Unfrozen; may Flat Poor drainage, openFrequently Floodplain and gravel be frozen 1, water inundated; deep locally i burial may be 1 required I:

1

I: TABLE 3: PHYSIOGRAPHIC REGION III - PEEL PLAIN

Map Terrain Type Landform Characteristics Surface Drainage Engineering Drainage SurfaceCharacteristics Landform Type Terrain Map 1 Symbol DescriptionThicknesses Soil Ground Ice TopograpGy Slope and GroundwaterConsiderations !

Inactive Stratified silt, sand, Medium to high Flat ! <30 Poor drainagePeriodically *p2 and Floodplain gravel I inundated Mh Hummocky Silty claytill Medium to high; Hummocky 9 to 15O Generally goodpoor Moraine occasional sand and high in in depressions gravel layers, organics depressions in depressions

m Rolling Silty clay till, Medium to high Undulating to rqfling 3O to 90 Generally good, high Moraine organic veneer in water table in depressions I depressions

MP Moraine Silty clay till Low to high: Flat to gently 3O to 9O Fair tugood drainage Plain mostlymedium undulating ! 1 Mv Moraine Siltyclay till <2 m Low to high; Topography is up to 20° Good drainage, high Depth to bedrock Veneer mostly medium reflection of i! water table in and bedrock type underlying bedrdck depressions may be factor in excavation

R Bedrock Sm Sm - siltstone, shale Undulating to rolling Variable Gmd drainageRipping generally mudstone, argillite ! feasible, blasting may be required locally TABLE 4: PHYSIOGRAPHIC REGION IV - PEEL PLATEAU

(Alignment Sheets16A, 17, 18)

-P Terrain Type Characteristics Landform Engineering Drainage Surf ace Symbol Topography DescriptionIceThicknesses Ground Soil SlopeGroundwater Considerations and

Fen . Peat and organic silt Unfrozen; small Flat to depressional <3 O Poor drainage I Buoyancy control areas frozen surface water, may be required

Pediment Silt, sand, clay, some Medium to high Gently to moderately 9O to 15O Fairdrainage Depth to rock coarse material and sloping variable (1 to 12 ml organics excavation maybe difficult where rock is shallow

Flow Slide Clay to gravel sizes Medium to high Variable Fair to poor

Colluvial Colluvium, predominantly Medium to high Gently to steeply 3Oto>15O Fair to good drainage Slopewash silt, sand, clay sloping

Colluvial Gravity-transported <2 mMedium to high Topography is Reflects Fair tu good drainage Veneer silt, clay, sand, some reflection of under- grave 1 underlyingbedrock lying rock

Alluvial Stratified sand and Low; sometimes Flat to gently, <3 O Surficially well Buoyancy control Flooplain gravel, minor silt unfrozen undulating, channelled drained, high water and deep burial table locally may be required I i 1 I \ TABLE 4: PHYSIOGRAPHIC REGION IV - PEEL PLATEAU

Terrain Type Landform Characteristics Surface Drainage Engineering Drainage SurfaceCharacteristics Landform Type&P Terrain Symbol Soil DescriptionThicknesses GroundIce Topography Slope . Groundwaterand Considerations

Active Stratified silt, sand, <3O Apl Unfrozen Flat Poor drainage;open Frequently Floodplain and gravel inundated water

Low <3O ' Ap2 Inactive Stratified silt, sand, to medium Flat Poor drainagePeriodically Floodplain and gravel inundated

Mm Ro 1ling Silty clay till Medium to high Undulating to rolling 3O to 9O Good drainage, high Moraine water table in depressions

MP Moraine Silty clay till Low to high; Flat to gently 3' to 9' Fair to good drainage Plain Mostly medium undulating

Mv Moraine Silty clay till <2 m Low to high; Topography isa Up to 20° Fair togood drainage Veneer mostly medium reflection of the high water table in underlying bedrock depressions

R Bedrock s s - sedimentary rock Flat to moderately Variable Good drainage Excavation may undifferentiated sloping requirie blasting if rock is tough

R Bedrock sm sm - siltstone, mudstone, Flat to moderately Variable Good drainage shale, argillite sloping

R Bedrock ss,sm - sandstone and Flat to moderately Variable Good drainage Excavation may be ss ,Sm conglomerate, difficult without some shale blasting in tougher formations I

TABLE 5: PHYSIOGRAPHIC REGION V - RICHARDSON MOUNTAINS

(Alignment Sheets18 (pat), 19, 20, 20A -E)

Type Landform Characteristics Surface Drainage Engineering Drainage SurfaceCharacteristics -PLandform Terrain Type Symbol SoilTopograpqySlope Description Ice ThicknessesGround and GroundwaterConsiderations

! pOv BogVeneer Peat <2 m High Flat to depressioqal e3 O Poordrainage ; ~uoyancycontrol standingwater may benecessary

Cb (P) Pediment Pebbly to bouldery, silt Medium to high Gently to moderately 9' to15O Fair to good . Depth torock and silty fine sand some sloping drainage (1 to 12 m) variable. coarse angular material . Excavation may be I ! difficult i

ClIl Colluvial Silt and sand, some Medium tohigh--Gently to steeply ' 3O to >15O Fair to good Slopewash clay sloping drainage

Ct Talus Gravity transported LOW Steeply sloping Up to. 40' Good drainageSteeper slopes may angular fineto coarse be unstable if bedrock debris disturbed cv colluvial Colluvium,predominantly <2 m Mediumto high Topography is Reflects Fair to good Depth to bedrock Veneer silt and sand, some clay reflection of under- drainage may influence underlying bedrock lying ease of excavation rock

Af Alluvial Fan Poorlyandsortedsand LOW Concave slope 5 - 15' Good drainage, some grave 1 subsurf ace flow

AP Alluvial Stratified, sand and Low, sometimes Gently undulating, )3* Surficially well Buoyancy control Floodplain gravel, minor silt unfrozen c hanne 1led drained, high water and deep burial table may be required TABLE 5: PHYSIOGRAPHIC REGIONV - RICHARDSON MOUNTAINS

Terrai n Type -P Terrain Engineering DrainageL,andform Surface Characteristics Symbol SoilThicknesses Description GroundTopographyandSlope Ice Groundwater Considerations

/

Active Stratified silt,sand, Unfrozen, may Flat <3* Poor drainage, open Frequently inundated Apl Floodplain gravel be frozen water locally

Inactive Stratified silt, sand, LOW Flat <3* Fair to good Periodically Floodplain and gravel; silt veneer drainage inundated

At Alluvial Stratified silt,sand, LOW Flat (3" Good drainage Terrace gravel; silt veneer except in scarps AV Alluvial Stratified sand, and <2 m LOW Topographyreflects <3 Good drainage Veneer gravel, minor silt underlying material

GP Glacio- Stratified sandand LOW Flat to undulatihg 30 to go Gooddrainage Possible source of fluvial gravel, minor silt granular borrow Plain

Mv Moraine Silty clay till <2 m Low tomedium Topographyis a up to 20° Fair to good Veneer reflection of drainage, highwater underlying bedroc% table in depressions TABLE 5: PHYSIOGRAPHIC REGION V - RICHARDSON MOUNTAINS

Engineering Map Terrain Type LandformSurface Characteristics Drainage Symbol Soil DescriptionThicknesses Ground Ice Topography Slope and Groundwater Considerations

R Bedrock s s - sedimentary Gentlysteeply to Variable Good drainageSandstone layers undifferentiated sloping may be difficult to rip

sm Sm - mudstone, siltstone, same as-above Variable Good drainage shale,argillite

ss ss - sands toneand Same as above Variable Good drainage May be difficult conglomerate to rip

ss ,Sm - sandstone and Same as above Variable Good drainage May be difficult conglomerate, to rip minor shale

R Sm, ss muds tone , Same as above Variable Good drainage siltstone,shale argillite, minor sandstone TABLE 6: PHYSIOGRAPHIC REGION VI - PORCUPINE PLATEXJ (EAGLr :'LAIN)

(Alignment Sheets20E, 20F - G, 21,22, 22A - E, 23, 24, 25, 25 (Part))

Terrain Type-P Terrain Engineering DrainageLandform Surface Characteristics Symb ol Soil Description Thicknesses Ground Ice TopographySlopeDescription ThicknessesIce SoilGround Symbol and GroundwaterConsiderations

fO Fen Peat, organic silt Unfrozen, some Flat to depressional <3O Poor drainageBuoyancy controls areas with high may be required ice fOv Fen veneer Peat, organic silt <2 m Unfrozen Flat to depressional <3* Poor drainageBuoyancy controls . may be required

Po mg Peat High Flat to depressional <3* Poor drainageBuoyancycontrols may be required

Cb (PI Pediment Pebbly to bouldery silt Medium to high Gently to moderately 9O to EaFair to good drainageDepth to rock and silty fine sand; sloping variable (1-12 m) some coarse angular excavation may be material difficult

Cm Colluvial colluvium predominantly Medium to high Gently to steeply 3Ot0>15O Fair to good drainage High ice content Slopewash silt andsand sloping materials are present near baseof slopes in valley bottom

Ct GravityTalustransported LOW Steeply sloping Up to 40° Good drainageSteeper slopes may angular bedrock debris; be unstable if silt and sand matrix disturbed cv Colluvial Colluvium predominantly <3 m Mediumto high Topography is a Reflects Good drainage Depth to bedrockmay Veneer silt and sand reflection of under- determine easeof underlyingbedrock lying excavation rock TA3LE 6: PHYSIOGRAPHIC REGION VI - PORCUIPIME PLATEAU (EAGLE PLAIN)

&P Terrain Type Engineering Drainage LandformSurface Characteristics Symbol Soil ThicknessesDescription Ground Ice Topography SlopeGroundwater and Considerations

A€ Alluvial Poorly sorted silt to LOW Concave slope 5* to 25O Good drainage, some Fm gravelsizes, grading subsurface flow from gravel at apex to sand and silt at base

1 AP AlluvialStratified sand and Low or unfrozenGently undulating, 3O to 5O Surficially well Buoyancy control Floodplaingravel, minor silt channelled I drained, burialhighdeep and water. may 'i table be required Active Stratified silt, sand Unfrozen; some Flat <3* Poor drainage, open Frequently Apl Floodplain and gravel frozen water inundated

Inactive Stratified silt, sand Low to medium Flat to undulating <3O Fair to good Periodically Ap2 Floodplain and gravel inundated drainage

At Alluvial Stratified sand and Low Gently undulating, <30 Good drainage Possible source of Terrace gravel, silt veneer steep frontal scarps except granular borrow I scarps

Av AlluvialStratified silt sand, LOW Flat to undualting <30 Good drainage Veneergrave 1

LV LacustrineStratified silt and <3 m High Flat with some <3O to 5O Poor drainage, some Veneerclay, minorsand and expression of standing water organics underlying deposits TABLE 6: PHYSIOGRAPHIC REGION VI - PORCUIPIME PUTEAU (EAGLE PLAIN)

MapTerrain Type EngineeringDrainage Landform SurfaceCharacteristics Symbol Soil DescriptionThicknesses TopographyGround Ice Slope and GroundwaterConsiderations

R Bedrock s - sedimentary Rolling tomoderately Variable Good drainageExtensive sandstone undifferentiatedmay layers sloping be difficult to excavate, shale generally rippable

R Sm - shale, Same as above Variable Good drainage

R Sm, ss - shale,etc; some Same as above Variable Good drainage sandstone

R Ss, sm - sandstone, some Same asabove Variable Good drainage ss may be difficult shale, etc. to rip I l l (AlignmentSheets 26, 27, 27A - I, 28, 29, 30 (part) ;I., 32, 33) nI Map Terrain Type Engineering Drainage LandformSurface Characteristics 1 Symbol DescriptionThicknesses Soil Ground Ice ToposraPhY GroundwaterConsiderations and Slope Fen Peat and organic silt Unfrozen, small Flat to depressional €30 Poor drainage Buoyancy controls areas with high may be required 1 ice

Fen Veneer Peat and organic silt <2 m Unfrozen depressional tuFlat <30 Poor drainage Buoyancy controls I may be required

Bog Peat High Flat to depressional <3* Poor drainage, Buoyancy controls I standing water may be required 30g Veneer Peat "2 m High Flat to depressional <3O Poor drainage, Buoyancy controls some reflection of waterstanding may be needed 1 underlying material

Pediment Pebbly and bouldery silt Medium to high Gently to moderately 9O to 15O Fair to good Depth to rock 4 and silty fine sand, sloping drainagevariable, excavation some angularfragments may be difficult I and clay Colluvium Colluvium, predominantly Medium to highGently to steeply 3'to<15' Fair to good silt and sand sloping drainage

-1 Rock Bedrock fragments with Variable Gently to steeply Up to 25' Good drainage These rock glaciers Glaciers interstital ice sloping, uneven surface are probably stabilized,further 1 study needed

I 1 TABLE 7: PHYSIOGRAPHIC REGION VI1- OGILVIE MOUNTAINS

Terrain TypeMap Terrain Engineering DrainageLandform Surface Characteristics sym bol Soil DescriptionThicknesses Soil symbol GroundwaterConsiderations andGround Topography Slope Ice

Ct Talus Gravity - transported LOW Steeplysloping Up to 45O Good drainageSteeper slopes may angular bedrock fragments be unstable if disturbed

Cs Rock slide Angular rock fragments LOW Moderate-lytosteeply >15* Good drainage May be unstable sloping and subject to more sliding cv colluvial Colluvium predominantly Mediumtohigh Reflection of ReflectsFair to good Veneer sand and silt underlyingmaterial under- drainage lying rock

Ev Eolian Wind blown sand or silt <2 m Mediumto high Reflects underlying 3O to 9O Gooddrainage High ice contents in Veneer deposit this material

Af Alluvial Fan Poorly sorted siltto LOW Concave slope 5O to 25' Good drainage, may gravel sizes, be some subsurface increasingly fine flow grained from apexto base

AP Alluvial Stratified cobbles, Lowor unfrozen, Flat and channelled <3O Gooddrainage, high Buoyancy control Floodplain gravel, silt, and sand water frozen small burialtable deep and may patches be required

Active Stratified silt, sand Unfrozen;some Flat <30 drainageFair Frequently inundated Apl Floodplain and gravel frozen patches standing water TABLE 7: PHYSIOGRAPHIC REGION VI1 - OGILVIE MOUNTAINS

&P Terrain Type L,andform Characteristics SurfaceDrainage Engineering Symbol SoilThicknesses Description Ground Ice TopographTI Slope and Groundwater Considerations

Inactive Stratified silt, sand LOW Flat undulatiqg <3O Good drainage Periodically Ap2 to Floodplain and gravel channelled inundated

At Alluvial Stratified sand and LOW 'Flatwith steep frontal <3O Good drainage Possible source of Terrace gravel, silt, veneer scarps frontal granular borrow scarps

Av Alluvial Stratified silt, sand LOW Flat to gently <3O Good drainage Veneer and gravel undulating

Lb Lacustrine Stratified silt, and High Flat to depressional <30 Poor drainage, some 3uoyancy control Basin clay, some sand and standing water may be required organics

LP Glacio- Stratified silt and High Flat to gently <3O Poor drainage Buoyancy controls lacustrine clay, some sand, and undulating may be required Plain organics ! locally

Lv Lacustrine Stratified silt and <2 m High Reflects underlying <3O Fair to poor Veneer clay, minor sandand material drainage organics

Gm Kame Complexly stratified Low or unfrozenSmall conical hills Up to 15O Good drainage Possible source of sand and gravel, minor and ridges granular borrow silt, occasional till lenses TABLE 7: PHYSIOGRAPHIC REGION VI1 - OGILVIE MOUNTAINTS

MapTerrain Type EngineeringDrainage ace Characteristics SurfLandform Symbol DescriptionSoil Thicknesses GroundTopography Ice Slope and Groundwater Considerations

Mr Moraine Ridge Gravelly sandy till Mediumhigh moderately sloping 9* to 25' Good drainage

Mv Moraine Gravelly sandy till <2 rn Mediumto high Topography reflects Up to 20° Gooddrainage, high Depth to bedrock Veneer underlying bedrock determines watertablein ease of depressions excavationdepressions

R Bedrock s sedimentary Hillyto mountainous Up to 75O Good drainage, Difficult toexcavate undifferentiated Variable mostly impermeable blasting may be required in all but shale and mudstone

R SC limestone, dolomite Same as above VariableGooddrainage Blasing probably required

R sm shale, siltstone, Same as above Variable Good drainage mudstone, argillite

R ss sandstone, Same as above Variable Good drainage Blasting maybe conglomerate required

R m metamorphic Same as above Variable Good drainage Blasting probably undifferentiated required

R mq quartzite Same as above Variable Good drainage Blasting probably required

R V volcanics Same as aboveVariable Gooddrainage Blasting probably undifferentaited required TABLE 8: PHYSIOGRAPHIC REGION VI11 - TINTINA TRENCH

(Alignment Sheets33A - 3, 34, 35, 36, 37, 38, 39, 40)

Terr ain TypeUP Terrain Engineering DrainageLandform Surface Characteristics s-1 SoilTopographySlope Description Ice Thicknesses Ground and GroundwaterConsiderations fO Fen Peat and organic silt Unfrozen Flat to depressional Poorly drained, high Buoyancy controls water table required, poor trafficability fov Fen Veneer Peat and organic silt<2 m Unfrozen Flat to depressional Poorly drained, high Buoy&cy controls water table required, poor traf ficability

PO Peat High Flat to depressional Poorly drained, high Buoyancy controls water table required thaw settlement may be a problem

POV Bog Veneer Peat <2 m High Flat to depressional Poorly drained, high Buoyancy controls water table required cm Co 1luvial Colluvium predominantly Generally Gently to steeply Fair to good drainage Slopewash silt andsand unfrozen; low sloping to medium where frozen

Ct Talus Angular rock fragments, Unfrozen Steeply sloping Up to 45' Good drainage Excavation maybe silt andsand matrix difficult i

TABLE 8: PHYSIOGRAPHIC REGION VI11 - TINTINA TRENCH

Terrain Type Landform Characteristics Surface Drainage Engineering Drainage SurfaceCharacteristics Landform TypeMW Terrain Symbol Soil DescriptionThicknesses Soil Symbol Ground Ice m?wlraPhY Slope and GroundwaterConsiderations cv Colluvial Colluvium, predominantly <2 m Usually Topography reflects Reflects Good drainage Veneer silt and sand unfrozen, low underlying bedrock under- ice contentif lying frozen material

EV Eolian Wind-blown sand and silt<2 m Unfrozen or Topography reflects 30 to 90 Gooddrainage . Highice contents Veneer frozen, high underlying deposits ice content where frozen especially in lows

Af Alluvial Fan Mainly sand and gravel, Usually Concave slope 9Oto>150 Good surface grading from gravelat unfrozen, low drainage, some apex to sand and silt ice contentif subsurface flow at base frozen

1 AP Alluviai Stratified sand and Usually Flat to gently <3* Good drainage, high, Buoyancy controland Floodplain gravel, some silt, unfrozen, high undulating, channelled water table deep burial may be organic veneer locally ice content required in inactive floodplain permafrost in of Stewart River patches beneath organics TABLE 8: PHYSIOGWHIC REGION VI11 - TINTINA TRENCH

Terrain Type Landform Characteristics Surface Drainage Surface Characteristics Landform Type Terrain Engineering Symb ol Soil DescriptionThicknesses SoilSymbol - Ground Ice TopographySlope andGroundwater Considerations

Gm Rolling Stratified sand and Generally Undulating hummocky 3O to 15O Good drainagePossible borrow Glacio- gravel, minor silt unfrozen, low sources fluvial ice content if Plain frozen

GP Glacio- Stratified sand and Generally Flat to very gently <3* Gooddrainage ’ . Possible borrow fluvial gravel, minor silt unfrozen, low undulating source Plain ice content if frozen

Gt Glacio- Stratified sand and Generally Flat to undulating, I <3O Gmd drainage Possible borrow fluvial gravel, silt veneer unfrozen? low steep frontal scarps source Terrace ice content if frozen

Gv Glacio- Sand and gravel, minor <2 m Generally Topography is a Good drainage Depth to bedrockwill fluvial. silt, frequentlyas unfrozen, low reflection of be a factor inditch Veneer discontinuous patches ice contentif underlying soil or , excavation frozen bedrock 1 M Moraine Gravelly sandy till Reflects overlying Variable Variable Undif f er- deposits Reflects entiated over- lying deposits TABLE 8: PHYSIOGRAPHIC REGION VI11 - TINTINA TRENCH

UP Terrain Type Engineering Drainage LandformSurface Characteristics Symbol DescriptionThicknesses Soil Ground Ice Topography SlopeGroundwater and Considerations

Ma Ablation Gravellysandy till RollingGenerally 9O to 15O Good drainage Moraine unfrozen, patches of low to medium ice content material

1 Mm RollingGravelly sandy till GenerallyUndulating to .rolling 3' to 9O Good drainageexcept Moraine unfrozen, some depressions for which patches of have poor drainage poor have of patches high ice content permafrost may occur in depressions

~p Moraine . Gravelly sandy till Generally Flat to gently <3* Good drainage Plain unfrozen, low undulating ice content if frozen

MV MoraineGravelly sandy till <2 m Generally Topography reflects Up to 15" Good drainage Depth to bedrock V eneer unfrozen, Veneer bedrocklow underlying will be a factor ice -content if in ditch excavation frozen TABLE 8: PHYSIOGRAPHIC REGION VI11 - TINTINA TRENCH

Map Terrain Type Landform Characteristics Surface Drainage En .neering Symbol Soil DescriptionThicknesses Ground Ice Topography Slope and Groundwater Considerations

R Bedrock i - igneous Rolling to steeply Variable Gmd drainage Excavation of this sloping bedrock type will be difficult

R m - metamorphic same as above Good drainage . Same as above

I R SS - sandstone and same as above Good drainage Same as above conglomerate TABLE 9: PHYSIOGRAPHIC REGION IX - YUKONtPI+ATEAU i (Alignment Sheets 41, 41A - D, 42, 43, 44, 45, 46, 47, 48, 48A - 1, 49, 50, 48E 1 - 6)

Map Terrain Type Engineering Drainage LandformSurface Characteristics Symbol DescriptionThicknesses Soil Ground Ice ToPograph4 SlopeGroundwater and Considerations

f0 Fen Peat and organic silt Unfrozen Flat to depressions+ <3O Poorlydrained, high Buoyancy controls water table required - poor i trafficability l fov Fen Veneer Peat and organic silt 2m Unfrozen 1 Flat to depression& <3a Poorlydrained, high 3uoyancy controls water table required,poor t traf f icability

Po Peat High ~ Flat to depression& €30 Poorly drained, high Buoyancy controls, i water table possible thaw 1 settlement

POV Bog Veneer Peat <2 m High Flat to depressional <3O Poorly drained, high Buoyancy controls 1 water table possible thaw settlement

Cf Flow Slide Gravity transported clay Unfrozen Moderatelysloping 'i 9 O to>lSO Fair to poor May be unstable to gravel drainage and erodible cm Colluvial Silt and sand colluviwn Generally Gently to moderate1j r 5O to 15O Fair to good Slopewash unfrozen sloping 1 drainage Cs Rock Slide Angularrock fragments Unfrozen Moderately to steepSy <2S0 Good drainage Excavation may be sloping difficult, more sliding possible TABLE 9: PHYSIOGRAPHIC REGION IX - YUKON PLATEAU

%P Terrain Type Engineering DrainageLandform Surface Characteristics Symbol DescriptionSoil Thicknesses ToPograPhyt GroundIce Slope and GroundwaterConsiderations

1

Ct TalusAngular rockfragments UnfrozenSteeplysloping '; >45O Good drainage silt and sand matrix I cv Colluvial Mostly silt and sand <2 m Unfrozen; low Reflects underlying : I. Reflects Good drainage Veneer ice if frozen' rock under- lying material

Af Alluvial Poorly sortedsand and UsuallyConcave slope 9Ot0>15* Good drainage, some Fan gravel,Fan grades from unfrozen, low subsurface flow gravel at apex to sand ice content and silt at base where frozen

AP AlluvialStratified sand and gentlyMostly toFlat <3* Good drainage, high Buoyancy control Floodplain gravel, minor silt, unfrozen;may undulating water table and deepburial may (Undifferent- organics locally be frozen be required iated) under organics

Active Stratified sand and UnfrozenchannelledFlat, <3O Fair drainage, some Frequently inundated Flooplain gravel standing water I Inactive Stratified sand and Mostly unfrozen Flat to gently <30 Ap2 Fair to good Periodically Floodplain gravel, some organics undulatingice high inundated content beneath organics -. -.

TABLE 9: PHYSIOGRAPHIC REGION IX - YUKON PLATEAU

=P Terrain Type LandformSurface. Characteristics Drainage Engineering

Symbol SoilDescription Thicknesses ,.;- ' Ground :Ice -I .: '.L? Topography ;;..-:-.: :. . . Slope and Groundwater Considerations

Mh Hummocky Gravelly sandy till, 9' to -15O. Good drainage,high Moraine granular lenses water table locally

Mm Rolling Gravelly sandy till 3* to 9' Good drainage.,high

Moraine water table - locally ,

HP Moraine Gravelly sandy till <30 Fair to quod drainage . Plain .~ .-

Mr Moraine Gravelly sandy till 9* to 25.' Good drainage Ridge -

Mv Moraine Sandy till . Generally . Topography reflect9 ::=t. Depth to bedrock will Veneer unfrozen underlying depositi .it; affect ease of excavation

R Bedrock i igneous rock Up. to175-0 Good drainage Bedrock, except for volcanic tuffs may be difficult to excavate in this region

R m Metamorphic rock Same as above

R S Sedimentary rock Same as above

R ss Sandstone Same a5 above

R V Volcanicrock Same as above HARW ASSOCIATES Cl97781 LTD.

tl

The occurrence of terrain units within a physio- graphic region can be determined quantitatively by measuring the kilometers of each terrain type within that region. Terrain typed alignment sheets with the pipeline routine and kilometer markers must be used for such a study. At the time of the writing of this report kilometer markers were unavailable so a quantitative study on terrain units was pot carried out.

Il OF ALBERTA I

Calgary, Alberta. February, 1979 K4239

On October 27, 1978 the name of”R. M.; Hardy & Associates Ltd. was changed to Hardy associates (1978-1Ltd. No change in ownership or scope of services is involved,

- 37 - HARDY ASSOCIATES Pl8781 LTD.

I 6.0 REFERENCES

I Bostock, H. S., 1936: Camacks District, Yukon; G,eol. Surv. Can. Memoir 189. , and Lees, E. J., 1938: Laberge map-area, Yukon; Geol. Surv. Can., Memoir 217.

0 1948: Preliminary Map, McQuesten, Yukon I Territory; Geol. Surv. Can., Prelim. Map. , 1948: Physiography of the Canadian Cordillera, with 1 special reference to the area north of the fifty-fifth parallel; Geol. Surv. Can., Mem. 247.

I 8 1963: Geology McQuesten, Yukon Territory; Geol. Surv. Can., Map 1143A. I , 1966: Notes on glaciation in central Yukon Territory: Geol. Surv. Can., Paper 65-36.

I 1970: Physiographic subdivisons of Canada, in Geology B. I and Economic Minerals of Canada; R. J. W. DougEs, Editor; Geol. Sum. Can., Economic Geology Report No. 1, ‘I pp. 10-30. Brown, R. J. E., 1967: Permafrost in Canada; Geol. Surv. Can., Map 124621. I Douglas, R. J. W., 1970: Geology and Economic Minerals of Canada, Geol. Surv. Can., Economic Geology Report 1. I Fyles, J. G., 1966s Quaternary stratigraphy, Mackenzie Delta and Arctic coastal plain, in Report of Activities, I May to October, 1965; Geol. SurvTCan., Paper 66-1. , 1967: Mackenzie Delta and Arctic coastal plain, & Report of Activities, May to October,1966; Geol. Sum. I Can., Paper 67-1, Pt. A.- , Heginbottom, J. A., and Rampton, V. N., 1972: Quaternary geology and geomorphology, Mackenzie Delta to Hudson I Bay; XXIV Internat. Geol. Congr,, Guidebook A-30. 1 I - 38 - 1 HARM ASSOCIATES t19781 LTD. B

I Gill, D., 1972a: Modification of levee morphology by erosion in the Mackenzie River delta, Northwest Territories, Canada. Institute of British Geographers; I Special Publication No. 4. , 1972b: The point bar environment in the Mackenzie I River Delta; Cdn. Jour. Earth Sci., V. 9. Green, L. H., 1972: Geology of Nash Creek, Larsen Creek, and Dawson map-areas, Yukon Territory; Geol. Surv. I Can., Memoir 364.

8 and Roddick, J. A., 1962: Dawson, Larsen Creek and I Nash Creek map-areas, Yukon Territory; Geol. Surv. Can., Paper 62-7.

' Hughes, O. L. et al., 1969: Glacial limits and flow ,I patterns, Yukon Territory, south of 65 degrees: Geol. Surv. Can., Paper 68-34. I , 1972: Surficial geology of northern Yukon Territory and N.W. District of Mackenzie. Includes map 13,19A (NTS areas lO6E, F, L, N; 107B, C): Geol. Squv. 'I Can., Paper 69-36. L.

8 HOdgSOn, D. A., and Pilon, J., 1972: Surficial geology maps, scale 1:125#000 of NTS areas (1061, hi# N): 'I Geol. Sum. Can., Open File 97. , Rampton, V. N., and Rutter, N. W., 1972: Quaternary I geology and geomorphology, southern and central Yukon (northern Canada): XXIV Internat. Geol. Congr., I Guidebook A-11. , and Pilon, J., 1973: Surficial geology maps, scale 1:125,000# of NTS areas (ll6N, O, P). Geol. Sum. Can., I Open File 167.

8 Veillette, J. 3.8 Pilon, J., Hanley, P. T. and Van Everdingen, R. O., 1973: Terrain evaluation with I respect to pipeline construction, Mackenzie Transportation Corridor, Central Part, Lat. 64O to 68ON. Environmental- B Social Program, Report No. 73-37, Information Canada. I I - 39 - I m HARDV ASSOCIATES r9ata1 LTD.

Johnston, G. H., and Brown, R. J. F., 1964: Some observations I on permafrost distribution at a lake in the Mackenzie Delta, N.W.T., Canada; Arctic, V. 17. I , 1965: Stratigraphy of the Mackenzie River Delta, Northwest Territories, Canada; Bull. Geol, Soc. Amer., V. 76. I Mackay, J. R., 1963a: The Mackenzie Delta area, N.W.T. Can. Dept. Mines Tech. Surv.; .Geograph. Br. , Mem. 8. , 1966: Segregated epigenetic ice and slumps in I permafrost, Mackenzie Delta area, N.W.T.; Geagraph. Bull. (Canada), No. 8. I , 1967: Permafrost depths, lower Mackenzie Valley, Northwest Territories1 Arctic, V. 20. ,I Monroe, R. Loi1974: Preliminary terrain classification and sensitivxty maps, Scale 1:250,000; ~eol.sum. can., Open File Nos. 117, 120, 121, 125, 131, 132, 144, 145, I 157, 210. Norris, D. K., Price, K. A., and Mountjoy, E. W., 1973: Geology, northern Yukon Territoryand northwesternDistrict .I of Mackenzie. Can. Ceol. -Surv,, Map 10-1063. ‘I

I Rampton, V. N., 1970: Surficial geology rftaps, scale 1:250,000, of coastal areas, NTS areas 107B-W part, 117A, 117C, 117D; I Geol.. Surv. Can., Open File 21. , 1972: Surficial geology map, scale 1:125,000, of NTS I area 107B-E part; Geol. Surv. Can., Open File 119. , 1972: Surficial geolgoy maps, scale 1:125,000, of NTS areas 97F, 107C, 107D and 107E; Ceol. Surv. Can., Open I File 96.

I 1974: Surficial geology and landform maps, scale 1:125,000, Of NTS areas 107B-W1/2, 117A-E1/2, 117C, I 117D; Geol. Sum. Can., Open File 191. I - 40 - I I , 1974: Terrain evaluation, Mackenzie Transportation Corridor northern part; Geol. Surv. Can. for the

Richardson, N. W., 1974: The Dempster Highway - engineering in the Arctic: M.Sc. Thesis, Dept. of Civil Engineering, University of Saskatchewan, Saskatoon, Saskatchewan. Ricker, K. E., 1968: Quaternary geology in the Southern Ogilvie Ranges, Yukon Territory; M.Sc. Thesis, Department of Geology, University of British Columbia, Vancouver, B.C.

, 1977: Quaternary geology of the North Klondike and Upper Blackstone River.systems, Southern Ogilvie Ranges, Yukon Territory, Canada, Dmpster Highway (EM 0-139); , Geol. Surv. Can. Open File Map and Legend 478. Tempelman-Kluit, D. J., 1970: Stratigraphy and structure of the "Keno Hill Quartzite" in Tombstone River-Upper Klondike River map-areas, Yukon Territory; Geol. Sum, Can., Bull. 180. Vernon, P. and Hughes, O. L., 1966: Surficial geology, Dawson, Larsen Creek and Nash Creek map-areas, Yukon Territory; Geol. Surv. Can., Bull. 136. Wheeler, J. O., 1961: WhitehQrse map-area, Yukon Territory; Geol. Surv. Can., Mem. 312.

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