PRESQUE ISLE, Maine — Chunzeng Wang is a mapmaker, a storyteller, an interpreter of the rocks, fossils and faults that reveal the comings and goings of land and sea over hundreds of millions of years.
And as this University of Maine at Presque Isle geologist translates the remnants of ancient life, he has upended geological beliefs about previously geologically mapped regions of the area around the Fish River chain of lakes and Scopan Lake.
When Wang first found the new fossils during his research last spring and summer, he said he was jumping up and down. It may perhaps be his biggest discovery, he said, adding that he was very surprised because he found fossils from both land and sea in the area.
All previous geological maps showed the Fish River chain of lakes to have formed from the sea. But the presence of both land and sea fossils changed those beliefs, he said.
“The Fish River chain of lakes area has a very unique and splendid topography,” Wang said. “These basins are made predominantly of red and green sandstone, siltstone and mudstone that contain plant fossils aged 395-380 million years old.”
As Wang describes the area, he talks about driving along Route 11, between Eagle Lake and Ashland, about the roller coaster ups and downs across the northeast trending ridges and valleys.
“I was wondering about these for years, but never became serious to find the answer because the area was not my research area till recently,” he said, explaining that his previous research and mapping led to his work with the multi-year project that is managed and coordinated in Maine by the Maine Geological Survey. And it is part of the U.S. Geological Survey StateMap Program.
The pandemic gave Wang more research days in 2020. And because of that, his discoveries were possible.
“Normally I would go to China for a few weeks for research,” he said. “But I stayed here and I was out for 105 days, a record for me.”
His findings relate to the composition of the valleys and ridges in the area, including new redbed and greenbed areas between Portage and Ashland; at Portage Lake along the Little Machias River; between Route 11 and the Aroostook River in Ashland; and a plant fossil site near Scopan Lake.
The common plant fossils are psilophyton, pertica (Maine state fossil), protolepidodendron, and taeniocrada of the early species with vein systems. These plants all became extinct many million years ago.
Wang said these findings explain the roller coaster nature of Route 11 in the Fish River area.
Most of the valleys are easily eroded because they are underlain by the relatively young redbeds and greenbeds basins that became sites of the current lakes.
“The ridges, however, are underlain by the older volcanic rocks that are more resistant to weathering and erosion, so that they stand high in relief and form ridges,” Wang said. “Without these valleys and ridges, there would be no Fish River chain of lakes.”
Historically, the areas in Wang’s current research were considered part of the older Silurian formation — the Silurian Period life was underwater from about 443 million to 416 million years ago — but Wang’s findings indicate that the Devonian period started with sea on a basement of land, changing previous beliefs about the Fish River chain of lakes during this time period.
“It was not a continuation of sedimentation in a pre-existing Silurian sea as thought by all other previous and current geologists,” he said.
Maine State Geologist Robert Marvinney supervises this multi-year geological mapping and research project and Wang’s field assistant for this work was UMPI senior Eric Bagley.
Not only are his findings significant for geological mapping, it makes the Fish River chain of lakes interesting for visitors, Wang said.
“With the discovery of this unique geologic feature, the big rift basin system, the Fish River chain of lakes that is already well known as a gem for its great recreational, landscape aesthetic, and cultural values, now becomes a unique geoheritage site with additional and significant value in earth science and education,” Wang said. “Recognition and promotion of the Fish River geoheritage would also provide local and regional economic benefits for years to come.”
Correction: An earlier version of this report misidentified the road running between Eagle Lake and Ashland.