5: FIELD MUSINGS ON GLACIAL AND GEO-POLITICAL BOUNDARIES IN WESTERN NEW YORK
Randy J. Woodbury, MS, adjunct faculty
woodbury@fredonia.edu (corresponding contact)
Richard A. Gilman, PhD, emeritus faculty
Michael D. Jensen, MS, alumnus
State University of New York at Fredonia
Geosciences, Fredonia NY 14063
INTRODUCTION
Glaciation was literally a heavy influence on the topography in Chautauqua County, New York’s westerly and southerly boundary with Pennsylvania. We will visit relic shorelines of pro-glacial lakes that occupied the Erie basin as ice near the Buffalo area dammed easterly flow; we will see that the shorelines are now tilted from post-glacial isostatic rebound and how geodetic evidence suggests the rebound continues. We will visit ice marginal features such as eskers, sub-glacial meltwater channels and deltas, and an apparent sub-aqueous recessional moraine. We will visit one or more “pop-up” structural features in the otherwise flat-lying Devonian stratigraphy, possibly the result of glacier-weight unloading. We will visit the inter-state boundaries to explain how George Washington, Benjamin Franklin and other early American leaders strategically determined the geographic interface between New York and Pennsylvania, to see the field challenges facing government surveyors who marked the lines, and learn how glacial-related geologic features defined the westerly line of New York.

5: FIELD MUSINGS ON GLACIAL AND GEO-POLITICAL BOUNDARIES IN WESTERN NEW YORK

Following old Early Lake Warren Beach

Passing Webster Pioneer Cemetery.
This is an undisturbed Lake Whittlesey high water mark.

Profile in Guidebook. To the south is a channel

Channel visible to the right between Ellicott and Webster Road
Channel visible to the right between Ellicott and Webster Road to the North.

Crossing Little Canadaway creek

Crossing channel that was parallel and under the ice front

Following Lake Whittlesey Ridge

Passing a grape vineyard to the right that was relocated
Passing a grape vineyard to the right that was relocated while many cubic yards of gravel was removed to build to prisons in Portland, New York

Farmhouse on wave washed delta deposits
Farmhouse on wave washed delta deposits reached by Lake Whittlesey waters. Antenna to the South is next to Luensman Overlook.

Distal part of the delta which contains the Portland Pioneer Cemetery.
Passing Cemetery Road between roads toward distal part of the delta which contains the Portland Pioneer Cemetery.

STOP 1. Eskers, get your rock hammers out here.
During either a period during a stage of late Lake Arkona or a period during an early stage of Lake Whittlesey, a long series of high-volume sub-glacial meltwater channels drained the southerly edge of ice that advanced southwesterly in the Erie basin to the area now Chautauqua County. The lowest of these meltwater channels carved out large amounts of local Devonian inter-bedded shales and siltstones as it emptied into, and formed a large delta in, either late Lake Arkona or early Lake Whittlesey. See Figure 1 for locations of the channel, the delta, and the delicate eskers likely formed near a wasting ice margin. We will observe evidence that waves washed the northerly ends of the eskers at the beach elevation of the pro-glacial lake that drained the Erie basin westerly during this glacial stage. At Stop Ten we will see apparent sub-aqueous recessional moraines that seem to correlate with glacial events forming the meltwater channel, the delta, the beach ridge, and the eskers.
At Stop One we will stand at the former water level – as surveyed by differential leveling for this project with the help of graduate student Bobbi Jo Gibbons – that snubbed the esker noses about 14,000 years ago, then walk the sinuous top of the esker and muse on what the feature contains within. We will get lucky as the grape-farmer owner has cut a cross-sectional path through the esker and we can take out our rock picks to better examine the core of mostly local and angular material with some sorting and stratification.

Profile in Guidebook where all levels of Lake Warren were crossed.

Rise onto Whittlesey beach.
Possibly due to the exposure of the Shumla Siltstone at this location. Crossing recessional moraines as we head up the hill.

STOP 2. Luensman Park (with restrooms also available here)
Luensman Overview Park sits atop the Lake Escarpment End Moraine. Views northerly give a glimpse of current Lake Erie and the higher and older relic shorelines of Lake Warren which United States Route 20 generally follows here, and of the even higher and older Lake Whittlesey which Webster Road follows here. Author Gilman assisted in the development of this gem in the county parks system by authoring a brochure on its geologic history, and he will give another of his hilltop lectures from the site. A nature trail, with its own guidebook at the trail head, is a nice addition to the original park and is highly recommended for those who can re-visit this stop at a more leisurely pace.

Notice the hummocks on both sides of the road.

Old road commissioned by the Holland Land Company
Old road commissioned by the Holland Land Company which passes right over the continental divide.

Kettle Hole Lake

Clever Store run by one of the original Geology Graduates
Clever Store run by one of the original Geology Graduates from S.U.C. at Fredonia

Crossing Drumlins

Stop 3 Pioneer Cemetery at top of Drumlin on Holland Land Company Town Line
We will cross and ride the ridge of the continental divide between the Great Lakes Drainage Basin and the Mississippi Drainage Basin as we move to this stop. We will pass Bear Lake, a kettle lake at the northerly end of a broad outwash plain. We will then cross perpendicularly across a drumlin field along a town line road surveyed and cut through wilderness more than 200 years ago. Our stop is at the summit of one drumlin at a spot offering great views toward Buffalo, the area thought to be the source of the most recent glacial lobe advance southwesterly in the Erie basin and also views to the northwest, the orientation of the drumlin field and the likely source of an older pulse of glaciation that traveled across the continental divide and beyond the southerly end of what is now Chautauqua County. After this stop, we will drive through the quaint village of Cassadaga and see its three inter-connected kettle lakes as we move southerly down the easterly side of a wide valley of outwash – a filled-in finger lake perhaps?

Three Kettle Hole Lakes

Ridge on Right covered by Drumlins.

Kame on Left

On Town Line Road
You can see several miles ahead as this road was also commissioned by the Holland Land Company in 1798.

STOP 4. Ross Mills Overlook
An excellent perch for pensive musings on geology, this is a stop above the pioneer settlement of Ross Mills with a breathtaking panorama of the wide outwash-filled valley below and the hills in Pennsylvania unreached by glaciers many miles to the south.

Cemetery in Valley Fill

Outlet of Cassadaga, Chautauqua, Conewango, and Chadakoin River
Straight ahead the outlet of Cassadaga, Chautauqua, Conewango, and Chadakoin Rivers all came together

Storage facilities for the Jamestown aquifer

STOP 5. Shale Latitude Stone
In 1786 and 1787, brothers Andrew, Joseph, and Benjamin Ellicott represented “Pennsylvania President” Benjamin Franklin – others represented New York – to blaze a survey line to Lake Erie along 42 degrees North Latitude, the boundary between the two states. About every 20 miles, astronomic readings were made by Andrew Ellicott and stones were there marked and set. We will visit a rare remaining stone. In 1781, New York had ceded lands west of the meridian through the west end of Lake Ontario to the United States, although that boundary was not established until US President George Washington ordered it surveyed in 1789 and 1790 when the Ellicott brothers represented the United States for that task. Pennsylvania hoped Chautauqua Lake would be in Pennsylvania. Figure Four is a map sent to Washington from the 1787 work of the Ellicotts for which Washington returned a letter of hope that Chautauqua Lake might indeed go to Pennsylvania, but Figures Five and Six are maps drawn by Andrew Ellicot filed, respectively, with the Holland Land Company in Amsterdam and with the Commonwealth of Pennsylvania, showing Chautauqua Lake and its surrounds were found by his survey completed and marked in 1790 to be in New York.

Salamanca re-entrant to the right.

STOP 6. LUNCH (with restrooms also available here)
Lunch at the Erlandson Overlook Park, where we have views of glacial-carved and outwash-filled valleys, including the former valley of a northerly flowing Allegheny River, and views toward the un-glaciated Salamanca Re-entrant where the river now flows south.

Passing Ripley Water Treatment Plant

Crossing Lake Whittlesey Beach

STOP 7. Three boundary monuments with an excellent story.
The northwesterly corner of New York is marked by granite stones set in 1884 to replace the 1790 marks placed by Andrew Ellicott. Another large stone monument is near here and we will read its ornate and elaborate markings. For this field trip, modern geodetic surveying was used to establish the latitude and longitude of the stones tied to the current reference ellipsoid to field-discuss the accuracies of the original surveys done centuries ago.

STOP 8. Pop-Up at Lake Shore
Pop-Up at Lake Shore by Ripley’s Wastewater Treatment Plant. Stops 8 and 9 show fascinating structural features as the usually flat-lying Devonian strata in Chautauqua County near Lake Erie has “popped up” – and perhaps due to glacier-weight unloading. Geodetic leveling research (Figure 10, Woodbury 1992) shows continuing local post-glacial rebound, so is present isostatic adjustment a key to these past effects?

STOP 9. Pop-Up at Ripley Beach
Stops 8 and 9 show fascinating structural features as the usually flat-lying Devonian strata in Chautauqua County near Lake Erie has “popped up” – and perhaps due to glacier-weight unloading. Geodetic leveling research (Figure 10, Woodbury 1992) shows continuing local post-glacial rebound, so is present isostatic adjustment a key to these past effects?

STOP 10. Hummocky Terrain where there should be lake bottom sediments.
Heading back to campus we will stop to see hummocky terrain that seems to correlate with the eskers we first visited, and the research theory in progress is that these mounds are sub-aqueous recessional moraines formed as ice calved away in a westward flowing Lake Whittlesey.

STOP 11. Lake Bluff Exposure at Lake Erie State Park
Lake Erie State Park takes us to a dramatic glacial stratigraphic section, a yearly adventure for geomorphology students and a pleasant Pleistocene place for our closing muse.