Reading Comprehension

PT125 · S1 · P2 · Q10 Drilling Muds

A free, expert breakdown of this official LSAT Reading Comprehension question.

Save & drill this skill — build targeted practice sets from questions like this one
Video walkthroughs — watch every question solved step by step
81 official LSATs — as questions, timed sections & full-length tests

Passage A Drilling fluids, including the various mixtures known as drilling muds, play essential roles in oil-well drilling.

Central Topic / Purpose

Drilling muds / to describe something and highlight a problem associated with it

Main Point

Drilling muds are carefully calibrated liquids important in oil-well drilling, but their complexity and the opacity of their recipes make it hard to study their environmental impact.

Central Topic / Purpose

Environmental impact of drilling muds / to describe the different environmental impacts of different drilling muds

Main Point

Water-based mud isn't very harmful and can be tossed overboard, while oil-based muds are potentially harmful and their disposal is much more tightly regulated.

Relationship

Both passages shared similar topics (drilling mud / environmental impact). Passage A felt a little more like it was trying to highlight a potential problem, while Passage B is written more in the style of neutrally describing the potential harm of OBM's. Overall, they seem pretty complementary and overlapping.

10.

Each of the following is supported by one or both of the passages EXCEPT:

Drillers monitor the suitability of
Supported by Passage A
The end of the 1st paragraph tells us that drillers are monitoring the behavior, flow rate, pressure, and composition of the drilling fluid (mud) they are using.
2% picked this
Correct
The government requires drilling companies
Why this is right
The end of Passage A all but contradicts this answer. Since many ingredients are kept secret, it sounds like the govt does NOT require companies to disclose all ingredients. Passage B never addresses the subject of whether or not companies have to disclose all their ingredients. We know that discharges are monitored, but that's not necessarily the same as "govt requires all ingredients to be disclosed".
Skill tested: Inference · how this choice captures the passage's function is the move to repeat next time.
82% picked this
In certain quantities, barite is
Supported by Passage B
This goes back to our correct answer on Q8. We know that barite is used as a food filler and is given to people before they get their gut X-rayed. Again, the language there doesn't guarantee that barite isn't toxic, but if we're using it as a food filler one would assume/hope that it's not toxic to humans.
4% picked this
Oil reserves can be found
Supported by Passage A
The 2nd sentence gives off the strong impression that oil-well drilling consists of drilling through layers of rock (so we can apply common sense and assume that the drill is going through rock in the hopes of eventually reaching oil).
9% picked this
Drilling deep oil wells requires
Supported by Passage B
The 2nd and 3rd paragraphs of Passage B make it seem like one recipe is appropriate for shallow drilling, while another is better for deep drilling. Requires is definitely stronger than I'd like it to be, but this is still a pretty reasonable claim. Ultimately, some support for a strongly worded answer > counter-support for a strongly worded answer (i.e. we have text that goes against choice B, so choice E is more supportable than choice B).
2% picked this

Continue the review in LSAT Lab

Save this question, watch the video walkthrough, and drill similar questions in your LSAT Lab account.

Save and practice this skill

LSAT Lab

Turn this review into a targeted study plan.

Save this question, drill more like it, watch the video walkthrough, and track your progress in your LSAT Lab account.

Start practicing free