Yet the landscape contains clues that point to an alternate theory. Many of the tributaries of the Lower Wisconsin River angle to the east where they join this westward flowing river; these have long been known in the geologic literature as barbed tributaries , and they indicate a river that has experienced a significant upheaval.
Too, the valley of the Lower Wisconsin River narrows as you follow it downstream, which is the opposite of what we see with almost every other river. Where it joins the Mississippi River at Prairie du Chien, the Wisconsin River curves to the north to join the south-flowing Mississippi; south of the confluence of the two rivers, the valley of the Mississippi River also narrows.
These geologic clues suggest that the modern river system does not reflect the system that once flowed across this landscape. The westward-flowing Lower Wisconsin River may not be exactly what it appears at first glance, and the bedrock terrace contains the key to discerning what river systems looked like here millions of years ago. The bedrock terrace, preserved within this time capsule of sorts, allows me to ask a fairly direct question of the earth: Was the original valley carved by a river flowing toward the west or toward the east?
As a geologist, I specialize in studying the processes and histories of rivers; more specifically, I study rivers that flow near the former margins of ancient glaciers. The idea that glacial activity may have caused the ancient Wisconsin River to flow to the east grew from many discussions I had with my former doctoral advisor, James C. Knox, before he passed away in Jim was the Evjue-Bascom professor emeritus of Geography at the University of Wisconsin—Madison and a pioneer in stream and soil research.
In the early spring of , however, improved topographic models, based on a new generation of laser-derived data called LiDAR, became available. Generated by measuring the two-way travel time of laser light shot from an airplane toward the ground, LiDAR data are accurate enough to identify ground surface elevations to within a few centimeters. Finally, we had a way to evaluate the elevation and slope of the ancient bedrock terraces.
Scientific research is often collaborative, requiring multiple voices to provide a breadth of insight, experience, ideas, and skillsets. Posing and answering the question of whether the Lower Wisconsin River valley was carved by an eastward- or westward-flowing river was no exception. We began by taking a series of hydraulic core samples along the terrace, driving hollow steel rods down through the surface sediment to the bedrock terrace and describing the cores we collected to identify the depth at which we struck bedrock.
We combined the LiDAR data, coring information, and core descriptions to precisely identify the elevation of the river-scoured bedrock terrace to within a few centimeters at a handful of points. Then we collected this information again and again at dozens of points along the valley to build enough data to identify the trend.
Those several weeks of data collection stand out in my memory. The anticipation of answering the east-versus-west question lent a tension to the fieldwork that I had never experienced in all my years of research. Within the first few days, I began to develop a broad sense of how deeply we should core at a given location depending on whether the bedrock terrace dipped to the east or to the west. The implications were tantalizing: A different configuration for the Lower Wisconsin River necessitates a different one for the upper Mississippi River, and for tributaries of the upper Mississippi River—the Black, Chippewa, Root, St.
Croix, and Minnesota. If this were true, it would prompt a reconsideration of the way we understand rivers across the North American continent. While I am by nature an early riser, I recall numerous sleepless nights in the summer of , thinking about the emerging work and waiting for the alarm to sound for another day of coring.
I would hope and, sometimes, even despair over the depth to which the core was penetrating, and obsess over the location and placement of new cores. My anxiety turned to excitement when I began to be able to predict the depth at which the core would strike bedrock if the terrace were indeed dipping to the east.
The data all pointed to a valley that, while occupied today by a westward-flowing river, was actually carved by an ancient, eastward-flowing river. The months that followed were filled with marshaling additional evidence to support this new interpretation of the river. We pored over the data to look for holes or flaws in the interpretations and presented our results to colleagues in the field for their critical assessment of the work.
Geological Survey. In plants, water molecules are drawn up capillaries called the xylem, helping the plant to draw in water from the soil, the USGS said. Beneath the continent's ice sit the Gamburtsev Mountains, a massive range with peaks and valleys that are about the same size as the European Alps, she said.
Intriguingly, researchers can tell that the river is flowing backward because the ice on top of it is aligned against the direction of the ice flow, Live Science reported previously. This alignment and the enormous pressure from the ice sheet above it push the water uphill, Bell said.
There are other instances in which water has naturally run uphill. For example, an 8. In addition, a study in the journal Physical Review Letters showed that small amounts of water put on a hot surface — a scalding pan, for instance — can "climb" tiny stairs made out of vapor if the water is hot enough, Live Science reported. Original article on Live Science. Laura is an editor at Live Science.
She edits Life's Little Mysteries and reports on general science, including archaeology and animals. She has won multiple awards from the Society of Professional Journalists and the Washington Newspaper Publishers Association for her reporting at a weekly newspaper near Seattle.
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Create a free Team What is Teams? Learn more. Rivers that flow "uphill" due to Earth's rotation Ask Question. Asked 6 years, 1 month ago. Active 1 year, 3 months ago. Viewed 7k times. My questions are two: Does this mean that the Mississippi would flow north if the rotation of the Earth stopped? Improve this question.
Community Bot 1. Michael Seifert Michael Seifert Or should we pretend that the shape is unaltered? A similar premise appears in this Phys. SE post. I've edited the question to clarify this. Add a comment. Active Oldest Votes. The Mekong, at least after it has left the Tibetan plateau. If one uses the actual gravitational potential for a non-rotating oblate spheroid, is the Gulf of Mexico at a higher gravitational potential than Minnesota?
Improve this answer. David Hammen David Hammen I imagined it would be something like that, but the map is so much better. The lakes in the gulf of Mexico and around the Caribbean are nifty too. I hadn't considered that.
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