A road where the buffalo roamed

Personally, I don't have fond thoughts of I-35E. In my mind, it is indelibly associated with long back-ups at the interchange with I-94 in St. Paul, particularly I-94 eastbound in the evening rush hour. But enough of complaints; if the interstate could think and speak, doubtless it wouldn't be happy with traffic jams either. I-35E happens to run in an old river valley north of I-94. The drainage was known as Trout Brook, and it gradually disappeared from the surface between about the 1880s and the 1950s (an overview of the valley can be found here).

Side Effects of a Misspent Youth

So, something on the lighter side, while I consider future directions for posts (see the last paragraph). Sometimes people relate one of their skills to a childhood interest, like someone who collected baseball cards developing an aptitude for math or statistics. These relationships are not always obvious, but I'm sure you can think back and say "I learned about [X] because I liked playing/reading/building/... [Y]." For me, I spent a lot of time reading dinosaur books, but I also managed to pick up a few other things, too. Here are some of them, in alphabetical order:

Practical guide to MNRRA/metro-area bedrock geology

I can't believe I didn't put up a post like this earlier. Here is a thumbnail guide to the various bedrock formations exposed within MNRRA and, by extension, most of the Twin Cities metro. Further information can be found in Ojakangas and Matsch (1982) or Ojakangas (2009), if you'd prefer a nontechnical level of discourse, or Mossler (2008) if you want a technical overview. The maps published by Mossler and Tipping (2000) and Mossler (2013) (see previous post) are also useful.

The formations of interest are the Jordan Sandstone, Prairie du Chien Group, St. Peter Sandstone, Glenwood Formation, Platteville Formation, Decorah Shale, and Cummingsville Formation. We'll take it from the top, or rather, the bottom, going in ascending order from the oldest rocks that are exposed (the Jordan Sandstone; there are older rocks below it, but they aren't exposed within MNRRA or in the central Metro. You can find most of them along the St. Croix, though).

A brief meditation on the joys of packrat middens

One more trip to the Quaternary, for a personal favorite...

Imagine someone has asked you to describe what an area was like hundreds, thousands, perhaps tens of thousands of years ago. They're interested in the ecology, the climate, and so forth. What could you use to accomplish this? If there are lakes and marshes, you might start by taking sediment cores and looking for pollen, which tell you what kinds of plants were present, and how the flora changed over time. If you're on the coast, you might look for deposits of shells, which are useful for describing the conditions of the water (salinity, temperature, how energetic the setting was) and for stable isotope analyses. If there's a lot of ancient wood, you might get into tree-ring data. In dry protected places of western North America, there is another type of paleoecological indicator: middens constructed by packrats.

Metro mammoths

Many states have had inventories published of Pleistocene mammal finds; I'm putting together a file for a future post. The most recent such report for Minnesota was complied by Clinton R. Stauffer and published sometime in the late 1940s. It is often cited as Stauffer 1945, but he cites several finds from 1946 and 1948. The journal is a proceedings volume for 1945, which is where the usual date comes from, but the Minnesota Academy of Sciences must have had some trouble getting it out that year. Anyway, 1945, 1948, the immediate point is that it's been a while.