Getting right to it, Turmoil is a time-constrained pipe building optimisation puzzle game. Your main goal, and main problems will resolve around getting all the oil in a level out of the ground and sold within one year. It does what it does and it does it fairly well. The pipe building is intuitive(Simply drag the mouse to where you want it), and everything makes sense. Oil only flows as fast as the smallest pipe, thus you need to make sure you don't have a bottleneck in your system. And if you pump oil up faster than you can carry it away then you spill it, incurring a fine. The game explains mechanics well and there are enough upgrades and level varieties where it does not become a chore or too similar to other levels.
A solid foundation, improved upon by hazards such as rocks and natural gas which can be used for profit as well, with the right upgrades, or just by adding it to your regular oil pipes so the pressure brings the oil up faster. As before, you may spill some if you bring oil up too fast, so be careful about what you drill.
To further the gameplay there is a solid campaign that last just long enough to be a good experience without overstaying its welcome. You need to buy the upgrades, lease land you think has a good amount of oil in it, and compete with 3 AI players trying the same. Eventually leading to auctions for shares which allow you to win the campaign once you have a majority share. Even if you are not into optimising things, the base gameplay is well enough and the game forgiving enough that you can get away with a profit just drilling for oil, though you may have difficulty making large profit margins.
Turmoil is a simple but solid game, build on a good concept with good execution at a competitive price. If you're looking for a few days worth of entertainment, Turmoil is a good choice at a good price.