BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA VOL. 47, PP. 1933-1960,4 PLS., S FIGS. DECEMBER 31. 1936

LOWER ALGONQUIN BEACHES OF PENINSULA

BY GEORGE M. STANLEY

CONTENTS Page Introduction...... 1934 Preliminary discussion...... 1934 Previous knowledge...... 1934 Methods of correlation...... 1935 The terrain...... 1935 Methods of measurement...... 1936 Description of data...... 1937 Tabular summary of data...... 1937 Shorelines near ...... 1937 General statement...... 1937 Nipissing...... 1937 Payette...... 1937 Cedar Point...... 1938 Penetang...... 1938 Wyebridge...... 1938 Interpretation of data...... 1946 Plotting of results...... 1946 Lower Algonquin water-planes...... 1948 General statement...... 1948 Wyebridge...... 1948 Penetang...... 1948 Cedar Point...... 1948 Payette...... 1948 General relations of the water-planes...... 1948 History of the Wasaga Beach vicinity...... 1951 Great Lakes history...... 1954 Review of Algonquin and Nipissing events...... 1954 Battlefield and Fort Brady beaches...... 1954 Studies in other areas...... 1955 Late Algonquin history revised...... 1956 Low water of late Algonquin times...... 1957 Conclusions...... 1958 Bibliography...... 1958

ILLUSTRATIONS Figure Page 1. Isobase map of the Penetang water-plane...... 1947 2. Detailed profile of the water-planes near Penetang...... 1949 (1933)

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Figure Page 3. Map of shorelines near Wasaga Beach...... 1950 4. Idealized profile across the shorelines near Wasaga Beach...... 1953 5. Idealized profile of water-planes projected southward...... 1957

Plate Facing page 1. Terraces bordering Penetang Harbor...... 1936 2. Cedar Point boulder terrace...... 1937 3. Payette gravel bar...... 1954 4. Marl-covered Payette beach...... 1955

INTRODUCTION Abandoned lake beaches in the northern part of the Great Lakes region have been known to geologists for nearly ninety years. They record a series of episodes that intervened between the Algonquin and the Nipissing stages, which have been well worked out elsewhere. Study of later Algon­ quin strandlines on Isle Royale in 1930 led the writer to doubt the inter­ pretation hitherto given these beaches. Researches were carried on in areas closer to the region of earlier studies. Those on Penetang (short for Penetanguishene) peninsula (Fig. 1, for location) were of especial value in interpreting the geologic history, and furnished the material for this paper. Field work was done in August, 1935, with the aid of a grant from the Penrose Bequest of the Geological Society of America, for which the writer is grateful. The work of Mr. James Calver, of Ann Arbor, in assisting with the tedious instrumental work, is acknowledged with appreciation. Results of work in the Mackinac area, done earlier in the summer under the same grant, are not presented in detail, for they cannot yield con­ clusive evidence until further supplemented.

PRELIMINARY DISCUSSION

PREVIOUS KNOWLEDGE The Algonquin and the Nipissing are the two most prominent old shore­ lines around the northern and northeastern Great Lakes. The Algonquin generally marks the highest limit of lake action and an abrupt change from the lake plain to the more rugged glacial drift; the Nipissing is characterized by heavily cut terraces and sharp, high bluffs.1 These two abandoned shorelines show an upward inclination to the northeast. The Nipissing has been gently and evenly tilted throughout the region; the older Algonquin shoreline was previously up-tilted to considerably greater degree. Thus, the Algonquin beach rises more

1 Frank Leverett and F. B. Taylor: The Pleistocene of Indiana and Michigan, and the history of the Great Lakes, U. S. Geol. Surv., Mon. 53 (1915) p. 316-469.

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steeply than does the Nipissing, and at a rate that increases to the northeastward. Both water-planes converge southwestward, toward the Port Huron outlet, and they are horizontal over the southern end of , below the hinge line through Richmondville and Grand Bend, with ele­ vations of 607 feet (Algonquin) and 596 feet (Nipissing). To the north­ east, they are separated by an ever-widening vertical interval, which in­ creases from 11 feet, in the area of horizontality, to 60 feet at Kincardine, 180 feet at Mackinac Island, and about 350 feet near Sault Ste. Marie. At the latter locality, the Algonquin has been uplifted more than 400 feet, the Nipissing less than 60 feet. In this vertical interval are a number of intermediate strandlines, which together may be conveniently called the “lower Algonquin beaches.” It is significant that, toward the northeast, where the Algonquin is farther from the Nipissing, these beaches increase in number. The Battlefield and the Fort Brady beaches, members of this group, will be referred to later. METHODS OF CORRELATION Fully half the field work consisted of the search for distinct strand features. In certain places, the shorelines are well developed, and it is not difficult to measure their elevations and to note that lake-action was protracted at that particular place and level. But the correlation of scattered features is more difficult. Measurements over a given area may disclose that the elevations of a prominent shoreline show a regular variation, and that the abandoned water-plane slopes with more or less definite rate and direction. It is not enough that additional shore features be found at accordant levels, for, in some favorable places, such as Cedar Point, shore features were noted at nearly all levels. The receding lake surface must have touched all levels, but the important stages in such a recession are marked by stronger development. The cut terraces are wider and more deeply indent the previous terrain; the depositional ridges are larger and more abundant, of greater length, and more com­ monly shut off bays or lagoons. In order to lend assurance to corre­ lation, all strong shorelines must show a decided coincidence with the level, or levels, in question. THE TERRAIN The Penetang peninsula is the northernmost part of , . It projects into the southeastern corner of in such a way as to expose its west and north sides to violent storms, and to leave more protected its northeast shore, which is heavily covered with glacial drift and deeply embayed. Much of the land is cleared and easily accessible by road. Therefore, and especially because of the topographic relations, it furnished an admirable place for study.

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The lower Algonquin features are well preserved about the bays in the northeast, and especially around fiord-like Penetang Harbor. The cut benches there are distinct and sufficient in themselves to measure the tilt rate. The west coast generally is less favorable for measurement, for good features are scarcer and more remote from the lake. Extensive Nipissing cliff-cutting destroyed many of the adjacent higher beaches. This explains the lack of evidence in the long stretch south of Lafon- taine. Most abundant data were thus derived, not from the exposed situations where wave action is most intense, but from the steeply sloping hills surrounding sheltered bays.

METHODS OF MEASUREMENT For measuring up steep slopes, an ordinary hand level (pocket level) was used in conjunction with a collapsible stadia rod. Over flatter land, where long sights were possible, a telescopic stadia level, mounted on a light tripod, was found easier to manipulate and to transport, if not quite as precise as the usual wye-level. Lake Huron served generally as the datum of reference, but the data at Wyebridge and west of Midland are based on railway and highway elevations, respectively. Except in the few cases where the use of aneroid is noted, all measurements were by spirit level and are reliable to probably a foot and a half. Final measurement of the shoreline was not confined to a single observa­ tion, but levels were run along it for considerable distances in some cases. The single values given, thus, represent the mean or the most satisfactory of a number of readings. These were made on the summits of the deposi- tional bars or beach ridges, and on the highest, even parts of the terraces, near the bluff. Such elevations cannot be far from the former lake levels. In general, beach ridges are believed to have been formed a few feet (rarely more than 6 or 7, and probably only 3 in protected situations) higher than the lake, but some of the bars or ridges measured were prob­ ably of subaqueous formation. Erosional terraces were usually 2 or 3 feet lower than the associated ridges, but, in a number of instances, this dif­ ference seemed abnormally great. Undoubtedly, each stage of the lake had alternating periods of high and low water. A beach crest, thrown up during high water, may have endured; whereas, erosion of a nearby terrace may have continued during low water and exaggerated the pre­ vious, and normal, difference in level between these two features. This condition pertains to all the water-planes discussed here, and it seems well borne out by the fact that characteristic Nipissing terraces, both in this and in other areas, are at slightly lower levels than are consonant with the well-established Nipissing water-plane.

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F i g u r e 1 . T e r r a c e s overlooking t h e S o u t h B a s i n Northwest view near Davidson Point. White house is on the Cedar Point terrace (698); large tree (extreme left) on the Payette (661); Nipissing (629) in the foreground.

F i g u r e 2. P a y e t t e t e r r a c e (660) s o u t h o f t h e h a r b o r Southwest view along hillside below range lights. Same terrace may be seen in the right distance with the Cedar Point terrace (above) and the Nipissing (below).

TERRACES BORDERING PENETANG HARBOR

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F i g u r e 1 . E a s t w a r d v i e w o f t e r r a c e East of Penetang Reformatory. Rodman stands on highest point of terrace (710), near base of bluff.

F i g u r e 2 . S outhwestward v i e w o f s a m e t e r r a c e

CEDAR POINT BOULDER TERRACE

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DESCRIPTION OF DATA

TABULAR SUMMARY OF DATA Elevations of the shorelines are arranged in Table 1, by localities and in the ascending order in which they were found during the process of surveying up from the lake. The subdivision into columns according to water-planes followed completion and study of the profile in Figure 2. In general, the localities are listed counter-clockwise around the Pene- tang peninsula. Locality descriptions are derived from maps. A few observations made by Goldthwait and Comstock have been included, but all measurements were made by the writer, and with a spirit level, unless otherwise noted.

SHORELINES NEAR WASAGA BEACH General statement.—Data on the shorelines near Wasaga Beach have been included in Table 1, but there are further essential facts that require elaboration. This region is much flatter than the other areas worked, and the shorelines are marked entirely by gravelly ridges, with no definite erosional features. Nipissing.—A broad, bulky sand and gravel belt, lying about a mile in from the lake, marks the Nipissing shore. High sand dunes (crests reaching to elevations of approximately 670 feet) and numerous sand ridges, slightly blown, overlie and obscure a great part of it, but gravel ridges (632 feet elevation) lie within the acute bend in the highway, half a mile northwest of Marl Lake, and northward along the east side of the road to the point at which it turns away from the dunes (Fig. 3). During Nipissing time, this barrier separated a large lagoon from the lake. A faint beach (631 feet), which crosses the highway half a mile southwest of Langman, and a bouldery ice rampart (634 feet) half a mile farther southeast, indicate the landward shore of this lagoon. Prob­ ably, a great deal of the material in the Nipissing barrier was derived from the bluffs to the north and was swept southward by storms from the northwest. Between the line of high dunes and Wasaga Beach are many post-Nipissing sand ridges, more or less deformed by the wind; only two of these seemed to be sufficiently intact shorelines to be worthy of measure­ ment (611 feet and 617 feet). P ayette.—The Payette beach (624 feet) was measured near the road 0.9 mile southwest of Langman Corners, and again (623 feet) about three-quarters of a mile away, in the south part of Lot 22. This beach is the most notable single find of the season’s studies. Gravel pits on both sides of the road showed the beach to be covered with a layer of marl. Excellent sections behind Livingston’s house displayed the marl

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deposit, a foot and a half thick and teeming with shells, in even, hori­ zontal strata overlying the beach gravel. The gravel beds dip southeast­ ward and thus indicate the prolongation of the beach, or spit, in this direction (PI. 4). It is a distinct ridge and controls the drainage of a small tributary to Marl Lake. About a quarter of a mile northward from the road, the ridge passes beneath the Nipissing dunes. Cedar Point.-—The Cedar Point shoreline is more extensively displayed than are the other lower Algonquin members near Wasaga Beach. It can be traced continuously for about 3 miles, and levels were run carefully along it, in an effort to measure the tilt rate. It is not a single, unbroken gravel ridge throughout this distance. Gullies make short gaps in it, and in places the main ridge dies out and is replaced or overlapped by another ridge, somewhat above or below. The measurements along it are presented in Table 2, which clearly shows a southward decrease in elevation of the shoreline. The total change is 3.9 feet. Although the localities thus represented are 3 miles apart, they are separated by only 1.3 miles in the direction of uplift (Fig. 3). A tilt of about 3 feet per mile is, therefore, indicated, and, though little weight can be attached to meas­ urements over so limited an area, this result accords well with the other data. Certain discrepancies in the table need explanation. In the stretches with mean elevations of 656.4 and 656.0, the beach trends away from the direction of dominant storms; wave action was probably less intense here, and the ridge was not built to as great a height. The most conspicuous anomaly (658.1) lies in the only stretch where the beach is broad and sandy and most nearly faced the westerly storms. Here, in bayhead position, it must have received material drifted along-shore from the northwest and must have been heaped higher by the waves. At both terminal places of this survey, the beach is a characteristic gravel ridge and trends approximately north-northeast; these stretches, therefore, seem well suited to show the change in elevation, already noted. Penetang.—The Penetang beach is marked by a gravelly ridge, which angles eastward across the north parts of Lots 20 and 19, Concession VII, Flos, from a point a quarter of a mile northeast of the cemetery (see cross on map, Fig. 3). The beach was traced for half a mile, along the south side of a gentle swell, which rises only a foot or so higher than the beach itself. In this distance, sixteen readings were made on the crest of the beach, averaging 677.2 and lying between limits of 676.4 and 678.0. Wyebridge.—The Wyebridge shoreline was not found here. It must lie far back from the present lake, and may be represented by the ridge (720) near Woodland Beach, which lies on a height of land that was probably submerged at the Wyebridge stage.

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T a b le 1.—Altitude (feet above sea level) of abandoned shorelines and description

Locality Nipissing Payette Cedar Point Penetang Other shorelines

M artyr’s Shrine 637 Bouldery 663 Bench 697 Strong 723 Distinct 734 Faint beach bench below higher on bouldery bouldery line near hill­ marked bluff hillside, its bench above bench, high­ top along west exact level 663 est principal 620 Sandy bench slope of hill somewhat step in this between north of questionable series Nipissing and Shrine 725 Narrow Wye River little beach near south end of above bench

Wyebridge 656 Possible 686 Terrace 712 Distinct 750 Strong beach, 200 and faint bouldery bouldery feet north­ bluff at base bench over­ bench above west of aban­ of hill due looking 686 712 doned rail­ east of old way station station

637 *Sharply de­ 658 *Terrace fined terrace

Midland 658 Flat near 698 Light grav­ 719 Terrace Gravelly junction elly beach on and bluff in beaches below Highway 27, golf course woods, east 719, at 712 1^4 miles south of across high­ and 708 west of Mid­ junction way from land, possibly Midland Golf shore feature and Country Club % mile southeast of junc­ tion

Penetang 639 Very mark­ 671 Bouldery 715 Faint 736 Strong 3 miles north ed terrace terrace and gravel beach gravel beach of town and ■with 25-foot bluff above near brook in woods by % mile east bluff, near 639 brook. of reformatory northwest Fainter beach corner of Lot in front, at 31, Conces­ 733 sion III, Tay

Penetang 672 Very mark­ 710 Strong 730 Weaker 687 Faint sandy 200 yards west ed bouldery bouldery ter­ bouldery ter­ beach deposit of locality terrace and race and bluff race and bluff at front of 710 above bluff terrace

Penetang 636 Bench be­ 660 Strongly 699 Terrace 720 Terrace 765 fLittle ter­ Near harbor low sharp marked with low bluff and low bluff races beside range lights on bluff bench with to south of overlooking small creek hillside in bluff rear range 699 bed on hilltop southwest light south of har­ part of town bor ranges

* From Goldthwait’s spirit levels, t By writer’s aneroid reading.

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T a b le 1.— ( C o n tin u e d )

Locality Nipiseing Payette Cedar Point Penetang Other shorelines

698 Bouldery 722 Terrace terrace and and low bluff low bluff to in line with east of rear ranges and to range light southwest

Penetang Harbor 659 fMarked 697 fMarked Up road terrace terrace southwest from head of harbor and millpond on Copeland Creek

Penetang Harbor 629 Terrace 661 Higher 698 Terrace 723 Distinct 684 Faint bench Along hillside at base of marked ter­ and bluff, bench above 743 Faint bench half a mile sharp high race below above 661 696 760 Faint beach west from bluff (unus­ bluff 696 Beach spit 764 Distinct, Davidson ually low for at south strong beach Point, across Nipissing) end of 661 at top of hill harbor from Penetang village

Penetang Harbor 708 Strong, 728 Strong About a mile broad sandy summit bar due south of bar beach beach of the Northwest facing north­ sand and Basin, in broad ward with gravel. This valley sloping hollow be­ and lower northward hind it beaches cut (south part of 698 Weak through by Lot 3, Conces­ bench in gully sion XV, front 722 Distinct Tiny) lower beach 717 Faint lower beach

Penetang Harbor 673 Strong 710 Strong (not to be found 720 Distinct Up road to gravelly gravelly here) gravel beach, southwest beach across beach across red brick from North­ road, farm­ road house on it west Basin, house on it 705, 697, 695 765 tLittle ter­ between Con­ 668 Faint lower Distinct race near top cessions XV beach beaches in of hill and XVI front of it, to south of road, 695 a long tombolo

t By writer’s aneroid reading.

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T ab le 1.— ( Continued)

Locality Nipissing Payette Cedar Point Penetang Other shorelines

Penetang Harbor 637 Back of 676 Strong sand 711 Strong 727 Distinct 696 Strong Up road to sandy terrace and gravel beach south' little bench gravel beach northwest below sharp beach spit west from along hillside spit in fields from North­ bluff. Buried across road road corner, northeast on west side west Basin logs and 663 Weaker half a mile from same of road leaves of beach in front northwest road comer Nipissing from Basin, as 711 time exposed in north cor­ 719 Fainter in ditch by ner of Lot 2, bench below roadside on Concession this terrace XVI, Tiny 709, 708 Dis­ tinct beaches 703 Faint beach

711 to 708 766f Distinct Strong grav­ bench along elly beach hillside spit about % farther north­ mile east east, and from same north of road corner Grosell’s as 711 Pene­ house tang Harbor and across road from Grosell house, in north part of Lot 1, Con­ cession XVI. I t encloses hollow, 25 feet deep 703 Distinct beach in front

SawfLog Bay ||' A series of 683 Very strong, 721 Strong bar 744 Broad, bold Probably a Up road to sandy wind­ gravelly bar beach across beaches in number of south from § blown ridges miles road about woods and weaker beach Crescentwood near lake, from lake, in half a mile crossing road, lines in addi­ Beach, 6 miles culminating south part of from lake summit of tion to those due northj^of at about 641 Lot E, Con­ 715 Good beach land here, a recorded, Penetang cession XVII, in front of mile from which, be­ village Tiny. It runs 721 lake cause of the northeast to 721 Bold rubble 735, 734, 732 dense woods, Payette farm, bar beach Weaker are not con­ then bends about % mile beaches to spicuous north. It en­ from lake north closes hollow, 720 Cobble 741, 734, 728 6 feet deep, beach 1H Weaker to north of it miles from beaches be­ lake low, to south t By writer’s aneroid reading.

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T a b le 1.— ( C o n tin u e d )

Locality Nipissing Payette Cedar Point Penetang Other shorelines

West of Saw Log 679f A distinct Point gravelly beach across trail in woods about mile from lake

Thunder Bay 664 Cobbly 700 Distinct No trace found bench and beach above here bluff, 0.9 664 mile south 710, 686 Much from bay, fainter just east of beaches road and 500 above and feet north of below road corner

Thunder Bay 664 Very strong 699 Flattish 685 Strong gravelly gravelly beach at beach across beach cut gravel pit embayment through by and jog in lowland to road, 1.7 road, 1.5 east of road miles south miles south and 1.1 miles from bay from bay south of bay 689 Strong 760 fA sandy 669 Short beach gravel beach windblown at east end of and flat, east shoreline, a 664 of road. Also, mile south lower and and half a successively mile south­ weaker west from beaches at shore of 684, 675, 671 Thunder Bay

Cedar Point 641 Very strong 668 Very strong 704 Very strong 723, 722 Strong 764 Very strong (12 miles gravel bar gravel bar gravelly bar. double­ gravelly bar. northwest of parallel to overlooking Leroux house crested beach Extremely Penetang). lake shore last. This and on it, west of 718 Fair beach faint sandy Up road to and not far other beaches road. below 722. ridges at 749, south from back, mostly built across Faint beach Possibly very 741, 732, 728 Cedar Point east of road. slight embay­ lines below at faint beach 813f Gravelly Hollow, 7 feet ment in hill­ 699, 695 lines at 714, beach on deep, behind side to east 712 height of land beach of road about a mile 674, 663, 660 south of Faint beaches Cedar Point above and by road below

755f, 720f, 699f A quarter of a mile west ;of road, step­ like bouldery benches along hillside t By writer’s aneroid reading.

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T ab le 1.— (Continued)

Locality Nipissing Payette Cedar Point Penetang Other shorelines

Lafontaine 631 Terrace and Removed by Removed by 713 Short, Ran northeast base of sharp Nipissing cliff Nipissing cliff vague grav­ from lake, up bluff, 70 feet elly spit, a line between high few hundred Concessions feet north XIV and XV from top of bluff 706, 704 Weak and obscure spits at top of bluff

W oodlsnd B each 625 Terrace at Removed by Removed by 690 Strong 720 Gravel Ran north­ base of sharp Nipissing cliff Nipissing cliff gravel beach, beach on east, up line bluff, 50 feet erosion erosion )/ 2 mile up plain at between con­ high road from Brook house, cessions I and lake and 1.4 miles up II K mile north road from of road, by lake and 200 gravel pit in feet north of field in south road corners part of Lot 26, Conces- cession II, Tiny Town­ ship 688 Low cobble Cobbly ridges beach looped adjoining this about knoll at 684, 682 100 feet south of road and % mile from lake. 687 This beach is a continua­ tion of 688, to southeast, south, and southwest Southeast of 635 Terrace at 666 Strong around broad 687, 681, 679, Woodland base of bluff broad gravel embayment; 678 Faint, Beach bar runs for continuous obscure beach 500 feet along levels along it lines across top of Nipis­ (685-689); it gully west of sing bluff terminates Tripp barn. near gully (686) at gravel west of I. T. pit behind Tripp house Tripp bam, in south part about % mile of Lot 27, south of the Concession I, 688 looped Tiny. Eroded beach. away else­ where. Gully shows 10 feet of stratified sand and gravel over clay.

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T able 1.— ( Continued)

Locality Nipissing Payette Cedar Point Penetang Other shorelines

Near Wasaga 660 Strong Beach gravel beach At road, 0.8 632 Gravelly across the mile north- beach beside southeast- northwest of trending road Langman Road, behind in north part Corners, a high dunes, of Lot 21, mile southeast M to % mile Concession of New north of Marl IX, Tiny. Wasaga Lake. Continuous Beach. levels run south-south­ east along this beach.

In surveying up Elmvale Road Langman 631 Low dis­ 624 Broad low 658 Same beach from Wasaga Corners. tinct beach, gravel beach as 660. Beach, about Yi mile at Lamont 652 Strong crossed exten­ west-south­ Livingston’s, beach below. sive series of west of Lang­ 0.9 mile west- wind-blown man Corners. south-west of sand ridges, Langman culminating Corners, in in peaks of Lots 23 of dunes about Concessions 670, and 1% VII and IX, miles from Flos. Gravel lake. pits show W 2 Closer to lake feet of marl are occasional over the beaches not beach disturbed by wind at 611 and 617.

At cemetery, 0.8 634 Ice ram­ 623 Broad low 656 Same beach 678 Distinct mile south- part, H mile beachbybarn as 652 gravel beach southeast of due west of west of ice 647 Strong trending east Langman cemetery rampart in beach in front from Marshall Corners south part of of it Palmer house, Lot 22, Con­ northeast of cession VIII, cemetery, in Flos north parts of Lots 19, 20, Conces­ sion VII, Flos Township

* Coldwater 635 * Obscure 672 * Sandy 706 * Broad 611 * Sandy bench in beach in pas­ beach above beach bouldery pas­ ture on same 647 ture, M miie hillside as 635 west of village

§ Beausoiei] 638 § Bouldery Island terrace

§ Giant’s Tomb 640 § Bouldery 685 § Cut bench 725 § to 711 § 746 § Cut terrace 666 § Cut terrace Island terrace Four beach ridges

* From Goldthwait’s spirit levels. § From Comstock’s aneroid reading.

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T a b l e 2.— Elevations along Cedar Point shoreline near Wasaga Beach From northwest to southeast, in the order levels were run.

Mean Num­ Eleva­ Approx­ eleva­ ber of tion imate From To Description Other beaches tion observa­ limits distance tions (feet)

660.2 17 659.1- 2000 500 feet south­ Southward in Very strong Strong gravel 660.7 east of road Lot 21, Con­ gravel beach ridge at corner, a mile cession IX, ridge through 652 to west northwest of Flos, to a garden and of this knoll Langman small clayey fields Corners knoll only a foot above beach level

658.3 13 657.4- 2500 Same knoll as About halfway Very strong, 658.9 above, going to school on continuous about south Elmvale gravel beach by east, near Road ridge west of Lot 21

(No dis tinct be ach at 500 A few hundred Elmvale Road Strong gravelly princi pal leve 1 in this feet north- near school beaches at interv al) northwest of house south­ 653, 651, a Elmvale west of Lang­ short way Road man Corners north of road

(No dist inct bea eh at 1000 Elmvale Road Southeast in Strong gravelly princi pai leve 1 in this Lot 21, Con­ beaches at interv al) cession VIII, 649, 648. Flos, through Fainter orchard to till beaches at knoll 643, 640

658.6 4 658.3- 500 Built southeast Gravelly spit 658.9 from till knoll in Lot 21

657.5 5 656.5- 2500 Near end of spit Southeastward Very strong 658.0 in Lot 21 to gravel beach deep gully ridge

656.4 11 655.4- 1500 Gully mentioned Gravel pit op­ Very bold Very strong 657.3 above south­ posite ceme­ gravel beach gravel beach eastward tery, by road ridge, cobbly spit at 647, to through fields corners a mile in places southwest of andfarmyard southeast of main beach in southeast Langman corner of Lot Corners 21

656.0 7 654.5- 2500 Cemetery, east- Where beach Intermittent Another gravel 657.4 southeast, curves to strips of beach a t 654, and curving southward gravel. Wave just south of to southeast and is better action prob­ cemetery in Lot 20, developed ably weak on Concession north side of VII, Flos embayment

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T ab le 2.— (Continued)

Mean Num­ Eleva­ Approx­ eleva­ ber of tion imate From To Description Other beaches tion observa­ limits distance tions (feet)

658.1 10 657.5- 2000 Continuing to Back of aban­ A very broad 658.7 south and doned farm beach of peb­ curving house by bly sand with southwest in roadside, 1}4 a few small Lot 20 miles south­ dunesonback east of Lang- of beach and man Corners 5 feet higher

656.3 2 656.1- 500 Near farmhouse Road in front Narrow gravel 656.5 in south part of house. beach ridge. of Lot 20 From ceme­ Beyond this tery to this point, it is point, the blown into beach makes high dunes in a broad semi­ south end of circle around Lot 21, Con­ embayment, cession VII. open to southwest

INTERPRETATION OF DATA

PLOTTING OF RESULTS The sheet of the National Topographic Series of served for horizontal control of the data and was supplemented, for the north­ west part of the peninsula (which it does not include), by the road map of Simcoe County, published by the Ontario Department of Highways. Comparison of elevations of the shorelines at Cedar Point, Penetang, Martyr’s Shrine, and Coldwater justified drawing the lines of equal up­ lift, or isobases, with bearing N 71° W. This direction can be considered accurate only to 3 or 4 degrees, but it agrees well with Goldthwait’s iso­ bases for the highest Algonquin beach over this district. Isobases for the Penetang shoreline are shown, together with elevations and the locali­ ties of observation, in Figure 1. All data were plotted in a profile, which extends for 24 miles parallel to the tilt-line (N. 19° E.) and at right angles to the isobases, as shown in Figure 2. Variations in the size of symbols are in accord with the strength of the features represented, and the center of each marks the significant elevation. As warping is negligible over the extent of

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F i g u r e 1.— Isobase map of the Penetang water--plane Dots mark localities of observation, with elevations for the Penetang beach.

this profile, the water-planes are shown by straight lines. For compari­ son’s sake, the Algonquin water-plane was added to the profile, according to the following figures, obtained by Goldthwait: 852 at Coldwater; 855 at Penetang; 840 at Wyebridge; 829 at Elm vale; 780 isobase near Mea- ford-Allendale.2 The level of Lake Huron-Georgian Bay has been taken as 580 for all diagrams, though 578.5 (Harbor Beach gage—August 1936) was used during the leveling work.

2 J. W. Goldthwait : An instrumental survey of the shorelines of extinct lakes Algonquin and Nipissing, in southwestern Ontario, Geol. Surv. Canada, Mem. 10 (1910) p. 24.

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LOWER ALGONQUIN WATER-PLANES General statement.—It is fortunate that the lower Algonquin beaches in the Penetang area are distinctly and separately displayed (PI. 1). Elsewhere about the Great Lakes, the intervals between them are not as clear. The writer has, therefore, named them in this area. Wyebridge.—The Wyebridge beach is best shown as a marked cut terrace (750) just east of the abandoned Wyebridge railway station, and as a strong gravel ridge (764) at Cedar Point. It was less commonly observed than the lower shorelines and is, consequently, not as well estab­ lished on the profile. For this reason, it has not been put in a special column in Table 1. Penetang.—The Penetang beach is to be seen in many places about Penetang Harbor, and is especially well developed (728) south of the Northwest Basin. It is distinct at Cedar Point (723), as are many of the other shorelines. In many places it seems to have been less well developed than the two lower beaches. An attempt to find this beach along the borders of Lake Couchiching, north of Orillia, was unsuccessful, wave action having been probably too weak to develop it there. Cedar Point.—The Cedar Point beach is named for its marked repre­ sentation at Cedar Point (704); the term might be as suitably applied to strong beaches at other levels there. This shoreline is conspicuous also, at most of the other localities (Pis. 1 and 2). Somewhat less well developed beach ridges were found from 10 to 15 feet below the Cedar Point shoreline. If these represent another water-plane, it is not parallel with the Cedar Point plane, but lies 5 feet closer to it near Wasaga Beach than near Penetanguishene, as shown in Figure 2. There is little likeli­ hood that such a plane would thus be less steeply tilted than the lower plane (Payette), and the data scarcely warrant such an assumption. Payette.—The Payette beach is named after the exceedingly bold gravel ridge (683) on which the Payette farm is situated, to the south of Saw Log Bay (PI. 3). In general, it seems to be fully as distinct as any other member of the group, and is the youngest pre-Nipissing beach in this region. GENERAL RELATIONS OF THE WATER-PLANES The substantial parallelism of the lower Algonquin beaches with the highest Algonquin, is amply demonstrated in Figure 2. This parallelism, together with the overlapping and submergence of the lower Algonquin planes by the Nipissing, make up the thesis of this paper. This condition was anticipated before the study of the Penetang area, but it was not anticipated that researches would demonstrate the fact so unequivocally. The steep tilt, about 3 feet per mile, was apparent around Penetang Har-

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bor, in not just one, but in three different shorelines, and became increas­ ingly certain from the accumulation of more data farther to the north and south. Although the old beaches near Wasaga are somewhat isolated from

F i g u r e 3.—Map oj shorelines near Wasaga Beach This area is located in the south-central part of Figure 1.

those farther north, their elevations, and the intervals between them, agree surprisingly with the water-planes projected southward from Penetang. Continuous measurement along the Cedar Point shoreline near Langman Corners served further to bear out the accuracy of the correlations, as did, also, the peculiar relations of the nearby Payette beach. Critical facts derived from the profile (Fig. 2) have been arranged in Table 3. The figures are highly significant, but it should be remembered that the slopes of the various water-planes cannot accurately be determined to hundredths of a foot. The tilt of the Nipissing plane, 0.42 foot per mile in the Penetang area,

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is just slightly less than that found by Goldthwait, over Bruce peninsula, though the difference is a small matter.

T ab le 3.—Critical facts concerning water-planes near Penetang as indicated by profile from Wasaga Beach to Giant’s Tomb Island* (Figures taken from Figure 2; length of profile, 24 miles.)

Slope Rise Elevation of Distance of plane Intervals be­ Convergence of of Water-Plane below Highest tween Succes­ of Successive Water- Plane (feet) Algonquin (feet) sive Water- Water-Planes Water-Plane Plane in 24 Planes (feet) per mile per miles (feet) mile (feet) (feet) South North South North South North

Algonquin 3.38 81 794 875 0 0 Î 90 Wyebridge not determined ? 785 ? 90 0.38 ? 37 Penetang 3.00 72 676 748 118 127 21 24 0.125 Cedar Point 2.875 69 655 724 139 152 35 38 0.125 Payette 2.75 66 620 686 174 188 (-1 0 ) 46 2.33 sub­ merged Nipissing 0.42 10 630 640 164 235 50 60 0.42 LakeHuron(580) 0 0 580 580 214 295

* The elevation (794 and 875) of the (highest) Algonquin plane in this table are based on inter­ polation from values obtained by Goldthwait. Whereas the figures must be substantially correct, further field work might eventually prove them in error by 5 feet or so. Accordingly, all figures in the fifth and sixth columns, as well as others, would be subject to alteration.

HISTORY OF THE WASAGA BEACH VICINITY The unique condition among the old shorelines near Wasaga Beach (Fig. 3), due partly to the general flatness of the region, is shown by diagram in Figure 4, and is to be explained by the sequence of events, as follows: (1) After the formation of the highest Algonquin beach, the lake with­ drew and eventually formed the Penetang beach (678 at Palmer’s). (2) The lake again withdrew to a lower level and formed the Cedar Point beach (656-660 near Langman). (3) Further lowering in lake level resulted in formation of the Payette beach at Livingston’s (624). The water-planes of these three beaches show general parallelism. The lowerings of lake level were presumably due to ice recession and shifting

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outlet much farther north, with extremely slight tilting occurring mean­ while. (4) The lake receded again to a still lower level and probably formed another beach, of which there is no record. This may have been repeated many times, for a long period ensued, during which a remarkable amount of tilting took place. The last, and lowest, outlet to be opened was the one at North Bay, which led to the sea through the Mattawa Valley. (5) Continued tilting slowly raised the North Bay outlet forcing the lake level gradually higher until the former Port Huron outlet was re­ opened. Until then, therefore, the lake was encroaching on the shores everywhere to the south of North Bay. Due to the flatness of land near Wasaga Beach, however, the advance of the surf could not keep pace with the rise in level. The waves built an embankment (the Nipissing barrier) along the shore and reared it steadily higher as the water level rose, while behind the embankment the land was flooded to form a broad, sheltered lagoon. In the quiet waters of this lagoon, the Payette beach at Livingston’s was well protected. Instead of being destroyed by waves, as was the case immediately to the north, it was submerged and coated with a thick layer of marl (PL 4). The lagoon covered a few square miles and made its own little beach line (630) and ice rampart (634), while the Payette beach (624) was submerged some 6 or 7 feet beneath the lagoon’s surface. Thus the history of the beach at Livingston’s is unique. This physiographic interpretation confirms a conclusion that has become increasingly evident, that the lower Algonquin beaches pass be­ neath the Nipissing. It is to be hoped that this beach will not be wholly destroyed for its gravel. (6) Further uplift of the North Bay outlet and tilting of the Nipissing beach brought the lakes to their present level. During the tilting, dunes were built along the Nipissing barrier at Wasaga. No doubt the beach at Livingston’s would not have been preserved be­ yond Nipissing time had the land sloped more steeply here, as it did near Penetang, or had the rise in level (until the Nipissing) continued farther, in which case the barrier would probably have migrated back, and over, the Payette beach. As an alternate interpretation, the Livingston beach (624) might con­ ceivably have been formed toward the end of the rise in lake level, already referred to, and Nipissing beach proper (632) might have been constructed as a bar soon after. This view is not necessarily supported by the fact that a great deal of erosion and cliff recession took place during Nipissing time, for miles north of New Wasaga Beach, and that much of the eroded material was probably swept southward and incorporated into the great

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Nipissing barrier at Wasaga. The fact that the Nipissing shore­ line has a very different trend (south-south­ west) from all the lower Algon­ quin beaches ^ (southeast) here is an objection B to such a hy­ pothesis (Fig. 3), a as is, also, the * M*1 contrast between g. the single Liv- ? ^ ingston beach § ■§> and the Nipis- B. B sing barrier with g § its multitude of § " ridges and great § g* e-f- mass of mate- % %. rial. But the co- 1 1

incidence of the Ok Cb ■Livingston ^ * beach with the § Payette water- ^ plane, projected | evenly with the o Cedar Point and S a 3 the Penetang g, planes from the region to the north, leaves lit­ tle doubt that t h e beach is lower Algonquin in age, and was formed in the manner outlined.

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GREAT LAKES HISTORY REVIEW OF ALGONQUIN AND NIPISSING EVENTS The lake history from Algonquin time to the present as given by Leverett and Taylor8 is briefly summarized. Perhaps, a theoretical, early Lake Algonquin existed in the southern part of Lake Huron, with outflow at Port Huron, before the ice had retreated far to the north, but no beaches relating to it have been found. Recession of the ice border opened up an outlet (Kirkfield) through the Trent Valley and lowered the lake by an unknown amount. Northeasterly uptilting raised this outlet until out­ flow began at Port Huron (and Chicago, for a briefer interval). At this time, the Algonquin (highest Algonquin) beach was formed. Continua­ tion of uplift caused the Trent overflow to cease and resulted in most of the great deformation of the Algonquin beach, while discharge took place at Port Huron. Meanwhile, the lower Algonquin beaches (Battlefield and Fort Brady) were formed. Ice recession from the Mattawa Valley opened a new outlet (North Bay) to the Ottawa Valley, and the lake was drained to a level perhaps 50 or 75 feet below the pass at Port Huron. Further tilting raised North Bay until outflow was again diverted to Port Huron, at which time the Nipissing beach was formed. Since that time, uplift has continued slowly, raising the Mattawa outlet more than 100 feet higher than lake level, but the drainage course has not changed.

BATTLEFIELD AND FORT BRADY BEACHES Leverett and Taylor4 and Goldthwait5 have described certain lower Algonquin beaches in the Mackinac Straits region, the Battlefield and the Fort Brady. The type Battlefield beach is a marked, gravelly ridge in northern Mackinac Island; the correlative water-plane was believed to slope at about 1.8 feet per mile over the surrounding area in the Lake Michigan Basin. Over the same region, the Fort Brady water-plane was supposed to slope about 1.2 feet per mile, being vaguely correlated with the type form, a cut bench at Sault Ste. Marie. Both these beaches show decided convergence with the Algonquin plane (slope about 3.4 feet per mile) in the same area; in other words, they had presumably been tilted only about half as much, or even less. The Battlefield and the Fort Brady planes were believed to continue their marked converg­ ing relations with both the Algonquin and the Nipissing planes south­ ward toward the hinge-line, and, accordingly, they would represent periodic pauses in the uplifting movement. These interpretations seem

8 Frank Leverett and F. B. Taylor: The Pleistocene of Indiana and Michigan, and the history of the Great Lakes, U. S. Geol. Surv., Mon. 53 (1915) p. 409-469. 4 Op. cit., p .429-438. 5 J. W. G oldthw ait: A reconstruction of water-planes of the extinct glacial lakes in the Michigan Basin, Jour. Geol., vol. 16 (1908) p. 470-476.

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F i g u r e 1 . O n - s h o r e v i e w Looking northwest at the bold gravel ridge (683) south of Saw Log Bay, which stands 12 feet higher than the hayfield in the foreground. Rodman on the beach in left distance.

F i g u r e 2 . R e a r v i e w Showing the same feature from the west, and the lagoon, 6 feet below the bar, occupied by cows.

PAYETTE GRAVEL BAR

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F i g u r e 1 . B e a c h g r a v e l s b e n e a t h N i p i s s i n g m a r l Payette Shoreline (624) on road from Wasaga Beach to Elmvale.

F i g u r e 2 . C l o s e - u p o f F i g u r e 1 Beach gravels dip to the southeast. Marl is more than a foot thick.

MARL-COVERED PAYETTE BEACH

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difficult, if not impossible, to harmonize with the findings in the Georgian Bay region here presented.6 It would seem best, at least for the present, to suspend use of the terms “Battlefield” and “Fort Brady.”

STUDIES IN OTHER AREAS Considerable study of a lower Algonquin shoreline (here called Minong), which is well displayed over a wide area on Isle Royale and the neigh­ boring shores of Lake Superior, has shown that it tilts at a much greater rate (2.6 feet per mile) than was to be expected for so young a stage. Its water-plane descends southwestward, toward the Nipissing, so rapidly that it appears to pass beneath it, although such a relationship was not actually observed. Thus, the question arose as to whether the Fort Brady beach, at least as old as the Minong, could slope only 1.2 feet per mile and remain above the Nipissing all the way to Port Huron. Studies on Bruce (Saugeen) peninsula strongly indicate a tilt of about 3 feet per mile for the lowest of the lower Algonquin beaches there, but further measurements are needed to determine the precise slope. Investigation of the Mackinac Straits area, just previous to the work near Penetang, yielded poor results. It seemed from the writer’s data, however, that a slope of nearly 3 feet per mile characterized the lower Algonquin beaches there better than do the Battlefield (1.8) and Fort Brady (1.2) correlations. It is uncertain just how the lower Algonquin beaches of the Mackinac region fit in with those near Penetang. On theoretical grounds, all the Algonquin planes here discussed should be separated by similar intervals wherever the total amount of Algonquin deformation is equal, provided that tilting between Algonquin and Nipis­ sing times proceeded always in the same direction. For instance, on Mackinac Island there should be a shoreline about 90 feet lower than the highest Algonquin (809-812) in order to correlate with the Wyebridge shoreline in the Penetang area (which is 90 feet below the Algonquin in that region). The type Battlefield beach (719) on Mackinac Island fulfills this requirement exactly. The counterparts of the Penetang and the Cedar Point beaches might similarly be expected near Mackinac at 682 feet and 662 feet, respectively. The group of so-called “Fort Brady” beaches at Mackinac and St. Ignace are at approximately these elevations, but they also cover the whole interval between.

6 Dr. Leverett offered the suggestion, in personal conference, that, possibly, tilting began earlier in the Lake Michigan Basin than it did in Georgian Bay, for the ice vacated it earlier. It is the writer's belief that the divergence between the two views is too great, however, to be reconciled in this manner.

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LATE ALGONQUIN HISTORY REVISED Considerable effort has been expended to discover the true attitude of the lower Algonquin water-planes. It is now quite clear that they have been tilted nearly as much as have the highest Algonquin, and are crossed by the Nipissing, thus necessitating a change in the interpretation of late Algonquin events. Lake Algonquin was not spilled out southward by a great, spasmodic uplifting movement, but, after the episode of Port Huron discharge and the construction of the Algonquin beach, it was drained to successively lower levels by the opening of new outlets. Ice recession over the high­ lands east of Georgian Bay must have made the necessary passages avail­ able as suggested by Taylor. Until the Payette stage, there were at least four such drops in level, intermittent between the lower Algonquin stages, which, altogether, lowered the lake more than 200 feet below the Algon­ quin beach. Lowering occurred at least once again and probably several times. Whether the Minong stage in Lake Superior is the equivalent of the Payette stage or whether it is a much later one and represents an additional drop in lake level is not yet certain. Discharge past North Bay and down the Mattawa ultimately brought an end to these events. Although some slight tilting accompanied these changes in level, the greater part of the remarkable deformation of the Algonquin beach was accomplished after Payette time. It may even have been antedated by the original Nipissing stage or by the first use of North Bay-Mattawa as an outlet. This uplift need not have been accelerated periodically, as Taylor7 has pointed out, inasmuch as the separation of the lower Algonquin beaches is due essentially to drainage rather than to uplift. Also, judging from present findings and the nearly parallel relationship between the Penetang and the Algonquin water-planes, the northward “splitting” of the upper group of Algonquin beaches8 would appear to be overestimated. The tilt of 3 feet per mile of one of the later beaches found by Johns­ ton,9 just west of Ottawa, seemed surprisingly steep to the discoverer and also to Antevs,10 who considered it a local anomaly. The steepness of tilt

7 Frank Leverett and F. B. Taylor: op. cit., p. 507. 8 Op. cit., p. 415-416, 430. Frank Leverett: Outline of the history of the Great Lakes, Mich. Acad. Sci., 12th Ann. Rept. (1910) p. 37 J. W. Goldthwait: The abandoned shorelines of eastern Wisconsin, Wise. Geol. and Nat. Hist. Surv., Bull. 17, 5th ser. (1907) p. 107, pi. 37. 9 W. A. Johnston: Late Pleistocene oscillations of sea-level in the Ottawa Valley, Geol. Surv. Canada, Mus. Bull. 24 (1916) p. 9. w Ernst Antevs: Recession of the last ice-sheet in eastern Canada, Geol. Surv. Canada, Mem. 146 (1925) p. 74.

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of the lower Algonquin beaches in the upper Great Lakes was equally unexpected.

LOW WATER OF LATE ALGONQUINÜTIMES Both the observed and the postulated crossings of the Nipissing beach by the lower Algonquin water-planes are illus­ trated in Figure 5. At the north end of this pro­ file, the water - planes shown in Figure 2 have been plotted. To the south they have been a extended by theoretical o dashed lines. Inasmuch as the Payette plane con­ verges only 0.37 foot per mile with the Algonquin in the Penetang area, it a* must be as nearly paral­ a lel all the way to its southernmost extent. Actually, the parallelism might be expected to in­ 6 £ crease, because of the >- diminishing slope of the -sa Algonquin beach. This a- conclusion is almost un­ avoidable, for the Algon­ quin beach must have experienced all deforma­ tions that affected the later beaches, and the at­ titude of the Algonquin plane over this district is well established. The Payette water-plane lies, OOÔ

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accordingly, about 115 feet below Lake Huron, near Grand Bend, and, therefore, close to the bottom of the lake. Presumably, the shore must have been about 20 miles distant from Port Huron during Payette time. Physiographic evidence of these low stages will sometime perhaps be found. The lake must have been still lower at subsequent stages and perhaps reached a minimum level at the inception of Mattawa discharge. It remains an important point to discover just how far below the Algonquin plane the lake level stood at that time. At North Bay, it may have been some 600 feet below the Algonquin plane, or nearly at sea level. Further study of the highest shorelines at North Bay and the tilt of the lowest Algonquin beaches may furnish a solution of this matter.

CONCLUSIONS (1) At least four distinctly separated lower Algonquin beaches, be­ tween the Algonquin and the Nipissing shorelines, can be distinguished in the Penetang area. They have been appropriately named. (2) The water-planes of these beaches lie essentially parallel to the Algonquin plane, and all of them must pass southward beneath the Nipissing. Unusual physiographic evidence of this fact is available. (3) Lake Algonquin was drained not by uplift, but, undoubtedly, by the opening of successively lower outlets to the northeast, each of the lower Algonquin beaches would seem to be associated with one of these outlet stages. (4) The great uplifting movement that deformed the Algonquin beach was not necessarily rapid. It was delayed until Lake Algonquin had been lowered some 200 feet by drainage, and perhaps until the North Bay outlet became active. (5) If the last is true, the lake may have been drained almost to sea level. At any rate, it stood for a time at least 115 feet below present lake level in the southern portion of the Huron basin, and then was further lowered. BIBLIOGRAPHY Antevs, Ernst: Retreat of the last ice sheet in eastern Canada, Geol. Surv. Canada, Mem. 146 (1925) 142 pages. Comstock, F. M.: Ancient lake beaches on the islands in Georgian Bay, Am. Geol., vol. 33 (1904) p. 312-318. Daly, R. A.: The changing world of the ice age (1934) 271 pages. Yale University Press. Goldthwait, J. W.: The abandoned shorelines of eastern Wisconsin, Wise. Geol. and Nat. Hist. Surv., Bull. 17, 5th ser. (1907) 134 pages. ------: A reconstruction of water planes of the extinct glacial lakes in the Michigan Basin, Jour. Geol., vol. 16 (1908) p. 459-476.

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Goldthwait, J. W .: An instrumental survey of the shorelines of extinct lakes Algonquin and Nipissing, in southwestern Ontario, Geol. Surv. Canada, Mem. 10 (1910) 57 pages. —1------: Isobases of the Algonquin and beaches and their significance, Geol. Soc. Am., Bull., vol. 21 (1910) p. 227-248. Johnston, W. A.: Late Pleistocene oscillations of sea level in the Ottawa Valley, Geol. Surv. Canada, Mus. Bull. 24 (1916) 14 pages. Leverett, Frank: Outline of the history of the Great Lakes, Mich. Acad. Sci., 12th Ann. Rept. (1910) p. 19-42. , and Taylor, F. B.: The Pleistocene of Indiana and Michigan and the history of the Great Lakes, U. S. Geol. Surv., Mon. 53 (1915) 529 pages.

U nivebsity or M ichigan, A nn Akbob, M ich. M a n u s c r i p t r e c e iv e d b y t h e S e c r e t a r y o f t h e S o c ie t y , M a t 15, 1936. R e a d b e f o b e t h e G e o l o g ic a l S o c i e t y , D e c e m b e r 26, 1935. P b o j e c t G r a n t 99-34.

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