Surficial Geology of the Center Lovell 7.5' Quadrangle, Maine

DE PART MENT OF CON SER VA TION Maine Geo logi cal Sur vey Rob ert G. Marv in ney, State Ge olo gist OPEN- FILE NO. 99-2 Ti tle: Sur fic ial Ge ol ogy of the Cen ter Lov ell 7.5- minute Quad ran gle, Ox ford County, Maine Author: Woodrow B. Thompson Date: 1999 Fi nan cial Sup port: Funding for the prepara tion of this report was provided in part by the U.S. Geo logi cal Sur vey STATE MAP Pro gram, Co op era tive Agree ment No. 98HQAG2052. As so ci ated Maps: Sur fic ial ge ol ogy of the Cen ter Lovell quad ran gle, Open- File 99-1 Sur fic ial ma te ri als of the Cen ter Lovell quad ran gle, Open- File 98-239 Con tents: 12 p. re port Maine Geo logi cal Sur vey Open- File 99- 2 Surficial Geology of the Center Lovell 7.5-minute Quadran gle, Ox ford County, Maine Woodrow B. Thompson Maine Geo logi cal Sur vey State House Stati on 22 Augusta, Maine 04333-0022 IN TRO DUC TION Geo graphic set ting This re port de scribes the sur fic ial ge ol ogy and Qua ter nary The Center Lovell quadran gle is locat ed in the White history of the Center Lovell 7.5-m inute quadran gle in south- Mountai n foothil ls of southwest ern Maine. The western bound- west ern Maine. Sur fic ial earth ma te ri als in clude un con soli dated ary is very close to the New Hamp shire state line, which is less sedi ments (sand, gravel, etc.) of gla cial and nongla cia l ori gin. than a mile to the west in the Chatham quadran gle. The map area Most of these de posit s formed during and after the latest episode extends in lati tude from 44o07'30" to 44o15'00" N, and in longi - of gla cia tion in Maine, within the last 25,000 years. Sur fic ial tude from 70o52'30" to 71o00'00" W. It en com passes parts of the sedi ments cover the bedrock over most of the quadran gle and are towns of Frye burg, Lovell , Stow, and Stoneham , includ ing a subject to many uses and envi ron m ental consid era ti ons. These small part of the White Moun tain Na tional For est. The vil lages in clude sand and gravel ex trac tion, de vel op ment and pro tec tion of Lovell and North Lovell are the prin cipal popula ti on center s of ground-wate r suppli es, siting of waste disposal facil iti es, and in the quadran gle. ag ri cul ture. A short segm ent of the Old Course of the Saco River passes The field work for this study was carrie d out in stages, first through the south ernm ost part of the Cen ter Lovell quadran gle. to gather data for the Maine Geologi cal Survey' s (MGS) sand- This river chan nel be came rela tively inac tive in the early 1800's, and- gravel aq ui fer map ping pro gram (Wil liams and oth ers, when a com bina ti on of floods and canal ex cava ti ons divert ed the 1987) and later to com plete the surfic ial geologi c mapping of the river to its new and shorter course closer to Frye burg vil lage Center Lovell quadran gle. Field work to up date earli er obser va - (Ander son, 1982; Thomp son, 1999b,c). The Cold River drains tions, and prepara ti on of the present report, were done in 1998- the western part of the quadran gle and emp ties into the Saco 99 for the STATEMAP coop erati ve betwee n the MGS and the River. Kezar Lake is the larg est and most im por tant wa ter body U.S. Geo logi cal Sur vey (USGS). in the map area, provid ing recrea ti on for many lo cal and sea- Two maps are as soci ate d with this report. The geo logic sonal resi dents. Several smaller ponds also oc cur in the quad ran- map (Thomp son, 1999a) shows the distri bu tion of sedi mentar y gle. units and in dicat es their age, com po siti on, and known or in ferred The to pog raphy of the Cen ter Lovell quadran gle is hilly origin. It also include s infor m ati on on the geo logic his tory of the and gener all y rises to ward the north. Eleva ti ons range from quadran gle, such as fea tures indi cat ing the flow direc ti on of gla - about 370 ft (113 m) above sea level (where the Saco River cial ice. This map, along with mapping done by the author in ad- crosses its southern border) to 1650 ft (503 m) on the sum mit of jacent quadran gles , provides the ba sis for the discus sion of Ad ams Mountai n near the north edge of the map area. Sev eral gla cial and post gla cial his tory pre sented here. hills in the east ern part of the quadran gle have been glacia lly The ma te ri als map (Thomp son, 1998) shows specif ic data stream lined in a south-southe asterly di recti on. used to help con struct the geologi c map. These data in clude ob - serva ti ons from gravel pits, shovel and auger holes, con struc tion Bed rock ge ol ogy sites, and natural expo sures along stream banks. Sand and gravel aqui fer stud ies by the MGS and USGS provided much Quater nary sedi ments cover the bedrock over much of the useful data on the strati graphy of the Saco River val ley, includ - southern half of the Center Lovell quadran gle, but out crops are ing num erous test boring and seis mic logs (Prescott , 1979; John - very com mon in the higher hills to the north. Most of the map son and oth ers, 1987; Wil liams and oth ers, 1987; and Tepper and area is under lai n by gran ite of Carbon ifer ous age, which is part oth ers, 1990). of an exten sive granit e body called the Se bago pluton. Me- 1 W. B. Thompson tasedim entar y rocks of Si luria n to De vo nian age occur in the older sur fic ial sedi ments (ei ther gla cial or non- glacial), while the northwest ern part of the quadran gle (Osber g and others, 1985). rem ainder was freshly eroded from nearby bedrock sources dur- Veins of granit e pegm ati te are found throughout the area. On ing the lat est gla cia tion. Lord Hill, Deer Hill, Col ton Hill, and Ad ams Moun tain, peg ma- Pit expo sures in the Lovell region have reveal ed up to 20 ft tites have been mined comm er cially for feld spar, amethyst, and (6 m) of till, and the thickness lo cally may be as much as 50- 100 rare min er als. ft (15-30 m). Till is thin on the tops of many hills, where bed rock is likely to be exposed. A ruled line pat tern on the geo logic map PREVIOUS WORK indi cat es areas where bed rock out crops are com mon and/or the till thick ness is in ferred to be less than 10 ft (3 m). Stone (1899) conducte d a recon nais sance of the Saco Val- Till is, by defi ni tion, a poorly sorted sedi ment (dia micton ) ley region during his state wide USGS study of Maine's glacia l in which there is a very wide range of rock and mineral parti cle gravel depos it s, but he did not report on the uplands that com - sizes. However , the texture and structure of indi vid ual till de- prise most of the Cen ter Lovell quadran gle. Prescott (1979) posit s vary depend ing on their source and how they were com piled well and test hole data, and carrie d out pre liminary sur- formed. In the Cen ter Lovell quadran gle, till may in clude a small fic ial and gravel aqui fer mapping (Prescott , 1980; Prescott and percent age of clay, but it has a dominantl y sandy or silty-sandy Dicker m an, 1981). Thomp son com piled a more detai led aq uifer matri x as a conse quence of having been eroded from coarse- map that in cluded the Center Lovell quadran gle as part of the grained bedrock. Till has littl e or no obvi ous stratifi ca ti on in Signifi cant Sand and Gravel Aq uifer Project spon sored by the some places. Else where it is crudely strati fied, with dis con tinu - MGS, USGS, and Maine Depart ment of Envi ron mental Protec - ous lenses and laminae of silt, sand, and gravel result ing from tion (Wil liams and oth ers, 1987). The U. S. Depart ment of Ag ri- sort ing by melt wa ter dur ing depo si tion. culture 's soil survey of Oxford County (Wilk inson, 1995) Stones are abun dant in this unit, and boul ders scat tered pro vided use ful ma te ri als in for ma tion for sev eral sites that the across the ground surface often in dicat e the presence of till.

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