I read the post on 學 vs. 學習, and I think one of the answers that was downvoted actually gave a pretty good speculation that agrees with my thinking and also one of the answers provided already.
In summary, I think learning/學 is a more inclusive term (as is often the case in Chinese when there is less characters) that does have a passive quality about it, although you still have to make a conscious effort if you want to learn something. Therefore I am inclined to say that learning is the generic term you use for acquiring knowledge or information.
Study/學習 is a more specific term that describes how this knowledge or information is acquired. The character 習 indicates practice or repetition that can become a habit or ritual if you want to interpret the meaning literally. However, you can also look at it as acquiring knowledge through a more structured or formalized way.
So you can say that I am learning Chinese without implying how you are acquiring knowledge about the Chinese language, whereas if you say that you are studying Chinese, it means that you are going through a specific process or method to acquire the knowledge. Of course, you can say that you are learning Chinese in many different ways (studying at a class being one of them), but if you say that you are studying Chinese in many different ways then you are probably taking classes, doing language exchange, doing research, etc.
Another way to look at it is that you can learn a lot of Chinese by being in China as a result of being immersed in the right environment, whereas it means something different when you say that you can study a lot of Chinese by being in China (unless you are referring to the fact that there are many schools or classes you can enrol in).