r

I ,,.

llllnole State Geologloal Surve7

Urbana• Illlnola

MINERAL RESOURCE RECORDS DIVISION

Ekblt::1w,, Q, E, M'S. 9S-ILLINOIS STATE

GEOLOGICAL SURVEY ·

Report on Examination ef Geolog1cal Oonditione alomg Proposed.

Route of Highway between. Palestine, lllinoia, and

Vincennes. Indiana

P9£P21f• The ebject of the examinat1oa was to asc-ertain the

geolog1cal c-sndit.ions along the prepoeed route -ef State Bond

Issue Highway Route No. 181, especially 11-.t portion of the

route tha.t lies ale:mg th-e ea.st sid-e of Robes0n Hills, north of

Vincennes, and to determine in what ma.aner- and ta ha.t extent

construction. of the high ay might be affected by these conditions.

Following the suggestion ef r. H. E. Surman, State Engineer et

Design, r. P. F. Jervis, Distric-t Highway Engineer~ Effingham~

Illinois. requested the examination, and he and his aesistant,

· :r. Riae, a.cc:c:>mpanied me during the oamination.

I. Vicinity of Robeson Hilla

Geologlc Sitµat19. 1'he Robeson Hills ooeupy sec. 9 ana the • 1/2

sec. 16, T. 3 ., B.. 10 • (Allison Township, La renoe Ooum.ty),

across the river and nort·h from Vineennes, Indiana. The:, oone-titute

a.n *island - hill• standing about 100 feet &beve the abash lowlands

that su:rrcund it. a.bash River skirts the east side et the hill

,. and ~ts. preset vaiitt isolates the hill frem the similar highland

half a mile aoros-, the rl~r ..

t ..

Ro~eaen Hilla are c-oraposed et bedrock man.tle4 an4

a1t1:rte4 Ylith sand and gravel and leeas. The bed::roet. wbioll appar­

eatlJ· lies p:ra.etioa.lly flat, eonsis_ta of the foll - l_ag -do - ar4

succesa1~n of strata:

Type of rock

Sandstone, generally soft but o-ontains some •flaga• layers of ba~d sa.ndstoae

Saale, sandy, micaceot1S, dark gray

Shale• arg1llaceous. duk gray

Sha.le-. black, ha.rd,_ sb·eety

Shale, clayey. dark

Limestene, ha.rd, foasil1ferous

Shale, dark

Th1otneae Feet

I

10

30

10

1

1

~-a a "

The bedrock is well exposed along the est side of the pr·esent

road and in the gullies in the ·cent.er of the east side of the hill.

Fatther north 1 t 1s l argely concealed by stU-flcial al.ope material

and farther south it 1s ho1ly coneealed by sand a.nd gravel, whieh

form.a a terrace-lite fea~e around tbe southeast corner Of the hill.

Band and gravel alse directly overlies the bedrock along the east

elope of the hill, as shown by exposures in the lane lea.ding to

the house sout.h cf the oeute:r et the ·east side. Loeas mantles the

hole hill. I~ varies in thickness according to its position, but

it rea.chea a m~imam depth of at least 30 feet. As shown by aahes

ta it, the lowermost part is gray and caloa.reoue; the middle put ie

bu.ff'• calcareous, and 'fiery fossiliferous, the fossils '"con~is·ti.ng of

severa1 kinds of small snail-shells; and the uppermost pai.-t is dark

. -·

yellow to reddish anil ts leaohed·and we.ath.e7ed to- a. clayey ·loaa ..

The ea.tut and gt-a.¥e1 at the sot.tthe~t part of the -

hill maintains -& fairly st.eep side slope• a1oag hlch there 1a ·

o.ana14e~able seepage whloh la more · or lees conoentJ'&t$4- at · .aome.

poi.ate. Consequently the Blll'fl.c1al material along the hole ·

slope ahows great•:r os- luae:t et:tect of sl.1p and. .alwnp and the

vegetation ts typically marshy despi'te the elope. At t-he places

here the aeeiage is concentrated., the rahy conditions are em­

phasized and rills run down the slope. The farmer h:o lives a.t the

foot ef the slope at the extreme seutbeaat comer of the hS,ll

baa 1nat.alled tile in a small a.mphithea.ter-llke recession la the

slope just above bis home to collect the seepage ateY in a

Ci.stern. Fro the cistern the .. a.ter discharges by overflow to

a succession of taaks at hioh his livestock may obtain d.r1llk-

ing wate~.

Farther nortb~ between the gravel terraces and the

house along the east aide of the hill, the slope becomes steeper

and there is again a marshy condition. Bedrock 1th overlying sand

and: loess ta exposed in the lane. leading to the house, and ln

se,rual gullies north of tbe house.. An appreciable spring

laeues near the head. Gf the first gully north of the houae.

Marshy cond1t1ona exist near the foot of the reduced slopes between

the gullin.. A conaid.aable 111Dot111t o~ ater 18 also n -. -ing

in the larger gullies, in llioh bedrock is tull:, exposed.

Bortb. of the gull.lea,. here bed.rook la ezpoeed. along

the road, the •lope is nearly ve~t1cal. The:ra is a thin mantle

of aurfteia.l ma.tei-ial 011er the beuook, b~t small $asses of it

ha.Ye l>:roken a y end· m<)"l&d. d01m the slope- in •eyebrow• - eltps. · -- -

lleareet ·the north end ot·- tbe hill the · elope i_e -aga.11'

r.fd~c,eci,. but lar.ge •"•• o-f t he · s$flciel JUat.eri:a.l . have- oved

~ the sl-oi,e ae 1anda\1des o.t 001181.derable Yal.Ulle'. these

alt4Qa ba~ -~d -,.&ttl time .... t1me ~ ,_ sa1· yeue, ~ · · eho .. l>y · th f aot t hat tbe t~s et 1a.,ge treee a,:e ou~ed.

upwarO., a c~tu,e -dev~l.o,ed a.tter the · lan.4'll4es had 41e.tube4 --- ·

the t-reea ho• the~ o:rlg1na.1 ei-eot po.stticm. Bedrock 1s .ocoa.sion-

llY ezJ)<>sed and 1s doubtless concealed by only a shallow eover-­

tng of aurf~o1al material.

Gu',Qdfal iaJeJprf)t lAAI• The bedfeok belongs

to the Peuaylvaaiau s.yat-em an4 ttpJreaen.ta the d.epoa1 u .lald

doWn du.r i ng all of one and pa.rt of another o-f the cycles of

s edimentation t ha t cha.ract-ei-ize the system. The ·strat deposite,d

during ea.ch cycle constitute a regulu series or cyolothem!,,

.h1oh 1• typi-oally compoaecl of (1) aan.d.stone or sandy shale a.t

the base. (a) underelay, (3) coal, (4) blaelt, she.et.y shale,

(5) limestene, and (8) gray argtllaoeoue oz saudy ah&le at the

top. -Although some members ot any oyc-lothea var, cone1denbly

1n -obaftet.e.r ad thion·eae and may dleapp.u looally, and

althoup some c7clothell8 lao-k some of the oharaet•~1st1o members

11aeaa othu-s oontain 844.ltiona.l minor strata, the continuity

ud rflgala~ eequanoe ot the o,-olo't eJUJ 1• . uob that they can

•• .~ecog111z.aa c,v-ez -g~t. ·areas -4 •o it baa bee ea.'t&l>-Uthe4

t'bat tlle7 puuat t.lot only ovu .,11 or Ultnoltl 'but: .also ~o.vu

dfat1eat- states. Jfeat-ly thi.$· c,y~"lell$ ba.va al~eatly been -

41ft.erentiated. 111 the Pennsylva.nian sy-atem ia Ill1'1o1s e,nd it ls

•~tad that· la area.a not yet st~e4 aclditional cyelotbema 11

-I-

Th geolo.glc events portrared by str·at-a ta ea.ch

eyolotbem ha-Y-e '"8n illtffP%ete4 as toll at- 1. Deposition et

sand, probably ·m inly on land surfaces and pos&-lbly in shallow

.seas, ae a oeiutequeace et.ther •f tilUn ot the •utll•·• 8\ll'face

or change of cllma.te, due to hich there was ~•n e4 aotivi'ly

la •~oaton and tnuporta.ttoa ot coarse detr1tua. a. r.ormatloa

of UBcterclay.. possibly r-epr-esenting a a-oll formed after eondl.tlona

ere again stabilised. 3. D·eposttton -Of vegetable matter (fYOID

which coal bed.a developed;) over intensive flattish sW8JIIJ$ -p~o'bably

a result of another change in climate so that vegetation _

nourished. 4. ltepoait1on of shale and limestone ln seas that

inundated the region blob had been -depressed by earth movements,

5. Reces-sion of" the seas follo ed by eJtoaion on the exposed lana,.

so that in some places ehannela ere out a.nd filled by the aand•

atone deposited dul:ing the first stage of the succeeding cycle.

The eycllcal recurrence of this particular sequence

of events durlllg the Pennsylvanian period as many times as there

are cyclothema seems a.t first almGSt incredible-. but the fa.eta

appear to substantiate the bypotheei-s,.. !he nearest analogy is

the repea.t·ed alternation of Cl)ld and warm c-limates th&.t must have

occurred during the Plets~ene period in o~der to account for the

eucceseion of glacial and interglaalal epochs.

Following the .Pennsrl n1an pe111od moat of th.e centn.l

part of tbe Korth Am.ertoan oonttnent haa remained. above the sea.

Erosion zed.11084· \he. region to a genelal p.laln 1n hi.eh the present

:riv•~ Y&1le7 and mee-t of their tributaries o-e 1nc1$ed.. Thia

sltuatton prevailed uatil the l>eg1im1ng of the Ple!stoo.en.e period,

When as a. result of a change t-e a markedly colder climate the

ftrat o:t ebraalcan continent.al glaole2' sp:read. south from C&nad&

far iato Un1\84 S\a.tets- !bie gl&oler as 41ea1pat.e4 by an

alll8l.1o.rated ollmak .amt f&7 thoUIJa'Dde of yea.re ooaditi0118 a1rrd.lar

lo tl\e pre•ent dieted.- 'f!um the~• aa a s-eout.Nnce of tb_e oolder . . . ~-

o1 ima te and the litYe.alon of the IHlOCnd 02> Xaaaaa glaeier t hi.ch

in timl · ae tliaelpa.ted by e. t-ecunnce of a •ewe eqaal>le climate

,bat «'Pin plPeklled tor ~oue&ade of Y•R•• A. a6oon4 reeu1'811ce

of· the oolde11 climate aocouated f~ the in.va.e·ion of the third

or Ill1n~ian glacl-e1\, and aft-er a.no-ther 1nteztven1ng period of

t-houaanda ot years of more pleasant climate, tbe third recurrence

ot cold climate brought ou"t the fourt.h or tecona1n gla-cier. • I

Elther or both the l.Vebrask.aa1 and Kansan gla0iers in­

vaded Illinoie. Drift older than th.e Illlnolan has been found

in eastern 1111.nois as far south as central On ford County, in

central Illinois as far south as southern Fayette OoUDty, and

in estern Illinois as fe:.r south as central Randolph County, but

the exact limits of the invasions have not been -definitely

determined. The Illinoiaa glacier extended beyond the i1m1te of the

older glaoi;atione in Illlnots. i-eaohing beyond Ca.rbend&le, Marion,

and Harrisburg. I-t left a ma.ntle of drift on h1eh a eo1~

profile several feet deep developed during the subsequent inteY­

glacdel. epoch. Streams :reexoa.vate4 111()&\ ot their valleys h1oh

had been mo~ or lees filled by the lllinolan drlft, and it aa -

at this time probably that aba.ah Rlff-1' out between Robeson Billa ·~

and the· Indlaaa upl~,~4oatng for a ah~t dlstuoe lb·

fone chann.el ia 1ts ·cld broa4 valley bet e~n Rooeaoa Bills

1111l4 Lawreno.ev111e.

The Wtscoasin glaci,er extended n..•:• ·farther aout.h 1n

Ulinois than Shelbyc,illa, Mattoon,. Cbarleattm, <-4 Paru. and

a. cemp1ementflZJ' dlat.ance i n i -nilana.. The c.;;tE1~- d.et-1ved fNm

1t:s melting pou-ed down the valleys- leading--_:: ···~1·-trom th.e lo~

front and ca.rrt.ed 1th them enormous amounts;.-.·,,Jt· -irti?:e1, sand,

silt, aad 0·1a7 milch s eventually. d&pos.tte.C ·:t.n ·l.h•. nllays,

more or less tilling them, The coarsest material . ae of course

deposited near-est the gla.e-ier and fine!'- and finer material

farther and farther down. the valleys~ As the glacial fr ont re­

ceded., th relative positions- of the various grad.es of material

migrated l1J)S1rrea.m, so that finer material gene%ally lies above -

coarser material in any deposit. In tha final stages of the

diss.ipation of the glacier, the volum·e of melt a.te:r beoame so

slight that it could carry only the finest material, and conse­

quently the ooa.r.ser, earlier out. ,a,sh material as eoveTed with

a. layer of silt a.nd c·l y. Wind blo ing across the va,lleys picked.

up the dried silt and clay and oarr1ed it up to and a.cross the

upla.nds, here it \tas t.ra.ppe.cl by the vegetation and ocumulated

a_s lo- ss. The shells of small snail.a hich lived on th ve·geta.~

ti-oa ere presened 1n the in -bltnlltl dust and may ne . be found

here. the loess has not ·been 1eacbed • . Since the tsoonsin glacier

disappeared, tbe strea,mf have be•n incising tbei~ channels in th•

out ash filling their valleys~ leaving it a.s terraces ab·o-ve the

present lowland. -eathering ~ also been in progress to to.rm a

aot1 on t he loeaa &11d oat ... sh ..

tever rain falls on the t-op or slopes

of the hills soaks r(l!adily into the 1oees mantle and also into the

sand and gravel., so t hat there is relat .ively little surface run­

of'f aft er o:rdi.,nary :ra ins. 'the uat-4.ir na,tural,ly tend.a to soak

dotmward and doe s so witU 1t encounter .s t he bedrook, li1bioh is

rela.ttvely 1ntperv1ous. The t1at ~r thence t1:mcr$ to move l aterally

through the basal part o'f t he loess o~ sand and gro.vel towards

any point o~ e-scape, and consequently issu.e~_fls seeps and springs

along the upper surface of the bedrook t1bereve~ it orops out. - - - - -

Wherever the surface of the bed.rook has a. marked slope, the move­

ment of the water i s intensified.

Bei ng composed largely of silt, t he loess bas the

oapaoity of adsorbing mu.oh water and also has t .he t endency to

slump and f l.ow r ea.dil.y when satur ated~ Consequently, whe rever

t here is ooneider able seepage through t he loesa on tbe slopes of

tib.e hi1ls , the -surficial material slumps and flows domi t he slopee

either in l arge slips or i n sma11 • eye- e rowct alips.. Wherever

t he bedrock has an a.ppreoia.bl e slope,. the surfioial mantle tends

to slide readily down the sloi:,e over the bed.rook surface , especially

when there i s sufficient wat er to soften the materials at the

conta.ot and t hus provide a lubr1oant to assist the movement.

P;robJ.g. In view of t he fact t hat t he .pr oposed route

for the hi ghway skirt s the east el ope of Robeson Bills, the

question as to whether const:ruetion of the highway would .encounter

or encouraee l andsli des was presented . Suitability of the ma.t .erial

proposed f or f ill s was also a question. A third queati011 r egarding

drai nage of seepage water developed during t he examinati on • .

Q;Qintea- I. Due to the fa.et tha t t he bedrook apparently ··

lies pra.otic·a.11.y fiat. t here seems no .reason to belie:ve t hat l arge

1.a.nd slides composed of whole ma.sees of rook and. sur.fi oial mater.1aJ.

should occur a.long the route. It is possible but no evidene.e i ndi­

cates that ther,e may be joints in the bedrock separating it in~

blocks which e-oul-d fall and &lide away. However, tne,re is a.bund:an t

eVidenoe in the form of slips and sl1:des t hat the surfio-1al !lla.te:tial.

has . does , and will slide down a.nd ove~ the Sllrl'ace of the bed.rook

vh~ver 1t is not properly 8Upported or has not attained its

angle of rest and whenever it beo-omes sufficiently saturated to

move . Along most of the s1de~slope 0£ the bill i the. t otal amount

of surfioi.al materia l t nat i s l.ikely to elide, especially if

disturbed by excavation for the highway, and the probable s ize

of the slips o.?e not suffici~ntly l a rge to create .gTave c onoarn,

but near t he nort h end the surfi c i al mat eria l hes moved bodil y i n

slides large enough to c ause real damage to a h i gh-aay . Further .

t he fill by which the hi ghway will b e r aised to the desired grade

will coun.ter r a.tber t han :favor t he for-matio.n of slides along most

of the way .

II. As the ili g b,m.y .a.long Robeson Hills t a to be con­

structed on gr ada level with the loo.al levees at either end ,

i t w-111 be oonsiderabl y hi gher t han the present road for ~ost of the

distance and consequently a large amount of fill mat erial wil~

b.e required.. According t o present plans, lTJateria.l for the

required fill w111 be obtained from a. bor:i-ow-pit situated on a

nose between two gullies nortb of the house at about -the ®nt-er

of the h Ul. Tbe m.at.erial in the berrow'"'i'it is all 1oesst except

th.er~ be some sand and gravel at t be bottom, between 1 t and the

bedrock. sh.a.le . This mate.rial should form a reaa.ona.bly satiafa.ot,ory

fill material under ordinary o-1.roumstanoes, but as it has so

gl:'eat a tendency to f low readily, tbe slope of the fill should be

-10-

red.uced to 3 tl or 4·:l. However, i n vieu of the fact that i;he outer

side of the fill Will be ex.posed e:r subraerged whenever \7abash

River rises to flood s t ages , it may be that mat eri al l ess

permeable and mp:re stable ffllen saturated than i .s loe$s should be

sought for t he £ill.

lII. 'the -gater t hat issues ns seeps and sp:ring-s and

satur ates the surficiaJ.. mat erial al ong the slope oree.tes undesirable

condi t i ons in tha t it aggr av~tes the tendency of the me.terial

to eli de , it m(;.y satur ate the mat erial so that it tends .ac tually to

now down t he slope , and it will affect the proposed f i ll si~ilar­

ly unless it is intercepted~

Reoomm,end&tiong, 1. I n order t o avoid so fe.r as

possibl e cre.at i ng or aggr av ating cond.itiotls- conducive to ' lands lidea

and sli ps , exoavation of the pres ent slopes should b e reduced

to a mi ni mum, and fills r ather t l't...an outs s hould be pl anned whel'ever

Possible . No partic-uler troubl .e acc ording t o present plans appears

i mminellt except nee,,.r the 11ort h end of the hill where a curve in

the- r oute. i s so pl anned t hat e onsider a-ol e cut and fill i s required

ju.st where the largest landslides have occurr ed. It woul d be

des1r~ble i f a t t his pl ace t he route could be ~ealigned so that it ·

run a oouple of hundred feet f arther f:rom the bl uff and thus

avoid any cut and heavy fill over the landslide. North of the

gullies along the oenter of the ea.st side1 where the bedrock

stand.a steeply; the anall masses of surl'1cia.l material. t hat <:ling

to the bedrock shoul d be :removed during construction, as it i s

obvious tbat they are eubjeot to slipping o.t any time and they

mi ght b~tter be removed during oonstruotion r at her tban after the

pavement t s in use. The sWBe procedure may be f olJ.,owed uhere the

slope i s leas t eep 1 as the terial. thu e. ,ove · during construc­

_,.,.,.:,.1"£0-xill - hereas ~ t rw d 1 t would be tio ~~Y be use in th

sted.

11:. If ·n l .oe·ssial ~.aterial 1 the proposed : orrov­

P t i s us cl · -Or f ·il ~ th slopes oi th_ f Ul s· ~ul be redu.oed to

·3:1 ~r 4.11. c_ rtainly le a -than l l/2t l or 211, because th lee s

ill e s ily ~ rb _ ater, beeo .e sutur t d , d tend o f lo

uhene ex l eh .iver .ris-es in flo-o and e t €} da to the fill .

If the :fi.11 b· constructed a f loes s , it ay be de-sir ble nd

future -develop ents yr qu re t hQt i be rip p it stone

or vel on the outer slope to proteo it f r o the de red ions

of the rive r - floods .

o e dv . taA s · .· y b& g· i ned i pl ns be .1· - e to

r e v lid u e i n fill t . r · i cial a teri on t e slope

t pe 11 ely t o p nd slide during or son t con-

strue ion. A tn{Jt~:n su·oh b ed.rook n.-y b e e oav ted d ri

const otion may be used to inore - e etab i -i · in the f"ll , i t 1

nots t is t o·:ry ,I en used ulo_ e ~ b eo.ause · t cons · sts ma.inly

o- sh le .d a.ft e_ .. t h een i n t he f 1 1 " ile) eatheri

soften he f -r en s of s hale so -v· .. t he e ue aze to0 et r

u t h f i-11 settle •. he surfioiu.l i Q s i xed . it

t e be oc o f'ill the o· ~1t"es and pores lef bet een the

ir1re 1: .. :t menta. The best materiel fer f ill is the $a n -

0 r ~Yel t ·too p~is S- the ter?aces 0 the st

co er o-f the bill . I r 1 t be possible to o t in by ·xo V "' tion

in aonn -tio itl the h i h _ y o fr a -or -O· . i t -suff"i ient

te~ial oft 1a tilld , it ould be f p~eferable to the cess,

as it would resist -&be unta.vor ;b e tion of fleod- · a.t er and wo ld

remain stable on a steeper slope. The bedrock d au:rfio i

mate.rial removed in tbe e·ourse o-f oonstruetion oould be ely

mixed wt tb woh -te·:e.1a.l P

111· ♦ Drains. should be tnsta.Ued 81:,ong the inner side

of t;he proposed hi lma.y ntierevelt there is conaiderable seepage

along the slope~ ·!hey sll.mtl d be pla.Qe4 so that t hey intercept

t.be seepage lJe"f ore 1 t reaches the f.111. be - 11 be needed

particularly (l) al.on the sand and -._.r avel terraces a t the south­

e as t .corner of t be hill; (a) 4on tbe .. ooded s1o e in the

p ture south o ~he l ne to the house at ~out thecenter o~ t he

e t side of the hill , and(3) along the slopes between the ll i es

jus north of this house . L ter it ay d v lop t hat dr ns

to inter c ept d 4~n ... ove cu s al.on t he i _ h ill be desira.bl.e

- d neQessa ry , i f serious Bl i des of surfioial mate1:i 1 seei:

i i nent. -hereve:r poss i l e ; the ~,:,quired dra i n should be

emp aoed _ong t be contact b een t he be .ock

i t is t he horizon of concentr ted seep a.

t he loese ., s

11. ilbur .H1liLs, north ~st of Russelv1lle

OWJlogio ~~:~lllilRD• The Wiibur Hille 0coupy seo ... 89

(Russell. To ship, .L.a ~1tena:a Oounty) -d. the south art of.sea. 20

(llentgomery Township, Ora · ord County} .,, !., 5 ll., R. l.O W. ,~

L1 e the Robesoll Hills., the-y oon-stitute an •1s1a.n4• of 1-Qess and

\111-.num tled be·d.rook surrounded by the la.bash lo land and

s.eparated fret.I! the adjaoen.t b.igblan.d by an overfl channel not

less than a t1J;Um.:rter of a. mile ide.. A meander of \7a.ba.sh R111er

skirts t .he northeast oo~ner of the hills.

Limited exposures of the shale and sandstone that

co1npzise the hill eoour a.lo~g some o f the small gullies that

carve the si,des of t-he hill. These strata e doubtless the

.same strat a that constitute th-e uppe,: part o-f the bed~ook in

the Robeson Rillsi as the dark sbal-e and cl-a.y are found l o ,

a.long the river. Bedroc.lt., -thinly mantled · th sand and silt,

forms a. terrace al.on the nort h side of the hill. Till and loe-ss

mantle the -hill. -- . 4

~gnnn~~S.• o p : tieular dif f ioul ties in eonstrueting

a. highway aoross Wilbur- Hills ls expected. The na.tur slopes

_ ill be followed - a,$ · ,e,l o se:Ly as poss1 ble, so 'the.re i l l be no

deep cuts amd ~e:h. outs as are r equired ill be direotly up a.nd

do ·n the slopes... ~ - --eve_;t-, tbe o·oourrenoe of a.t leas t one sp:ring

in. the hill ind:ioates that during and af ter oonstn;.0tion some

attenti on should be given to actual or possible seepage so tb: t

di-airus may be installed where neeessal'Y be£ore damage t~ the

~ :vement results. Tne existence of bedrock at sballe dept n

along the north side ef the hills ould be o-onsidered

when planning the structure by hich the high ay 111 '-be

carried acxos_s a small stream bordering the west and north side

cf the hill.

·1:t1.. Upl d from Heathsville to Pal estine

GtoJ.og.c Sis~19ti91. Tbe new hi ~h ay will f ol l o .

generaJ.ly the pr-esent irregularly diagonal road from Heathsville

to Palestine. It crosses secs., ? and S, T .. 5 N.,, , _.- 10 r1. 1

sec. 1, T. 5 N., R. 11 W .• , and sees .. 36, 25, 26, 23• 14, 11 1 and

2 , T. 6 J .• , R.. 11 • The surf ioia.l material over all the area.

is loes~, overlyi lllinoian till, hich in turn lies upon

bed.roe ~ Bedrock crops out in many of the gull ies and small

yalleys ,. indic tin -~-\ bat the . antle of lees · and till ts

probabl¥ nevel' -_ oh more t han -ent - fe t thiok ..

Fr.om numerous exp.o-sure-s i n the ener l reg ion it is

known ~hat the bed.roe consists of the follo i nu str t a 1 in

domnra.rd su~.c.e sa1on:

Type of materia1

Sandst.one (lteTom ·f'oJ11D.a.tien), mas.sive • frta.b-le, coarse in lo e:1t_·Jnii-t and pebbly at ba.se

Shale,, 2"a.yish b.~ue

Li estone, hard in upper part; d wirk, impure, and

oladdy in lo. er J)art· (Lo ~, r Ltvingston o.r wrea;t Franklin forU11a.tion ef !ndian°')

Ooa.1

UndeN-lay

Sha.le~ argillaoeous, rayish.~blue

"Thie ess ·reet

2-5

1

o - a 5 - 7

s~4stone,. f~~g1lfY-; to sha.ly 10 :, ~ I

All of these strata are belieYea to occur in stwoessien just

bele. the strata exp0sed i..n obeaon Hills,. a.nd represant the next older oyolothem, except that the top sandstone is the basal member of the series in ~beson Hills.

~9l11$9\11• No partl~ular trouble should be encountered

in consrtruoting the high ay al.on the proposed route., unless some

of the outs s hould happen to be so d.eep that they enoounter bed­

:roc, in hi0h ease seepage t the bedrock surface may requii-e

drains. ln some cases seepage in sufficient quamtity to jastify

drains may also occur at the oontaot betwe-en the loese an the

.. , -15-

ttll~ This s i tuation appears likely t o occur only 1ll the

NE ! corner Ntl' . 1/4 seo. l, T. 5 M. ,. R. 11 w., and i n t he NE . 1/4

see". 11, T! 6 N .• , R. 11 W.

Owing to t he faot that bedrook i s known t o crop out

i n the '7all s of t he valley i n the vicinity of Palestine , i t may

be poss i ble t bat i t l ies at no grea t eep t h b elnw t he lowl and

also. Consequentl y :i,. t i s r ecommended that a t least one and

possibly more test-boringg be ma.de at the proposed site for the

bridge ove~ Lamotte Creek at t he south si de of Palestine before the

final locati on and pl ans for the footings of the pi er s a r e chosen.

Ap~ -·~ • Le ghton, Chief

/

Areal

, -

Divi sion