Don't read it seriously.... read with a cool mind, without any distraction and when you really want to read.
If there is something you don’t understand...read it twice...go through the particular topic...for example petrography...you search the term in google...see some other papers on similar aspects, try to understand the meaning and basics of the topic.
Usually the abstract will give the zest of the paper.. and you have to read it first.
The conclusions part will give the what the author really want to tell about the results of his/ her research.
The title has to be understand to be in totality sometimes...sometimes its a particular word or two...for example...Chemical characterization of Zircon..it will give whole information about whats going to be in paper.