Question

read the passage. human activity and earthquakes when americans think of earthquakes, they tend to think of california, a state known for its frequent seismic activity. in recent years, however, people in arkansas, colorado, kansas, new mexico, oklahoma, and texas have been feeling the ground shake more often. an increase in oil and gas drilling in these states has led to \human - induced\ earthquakes—those resulting from human activity. when wastewater is disposed of during gas and oil drilling, the water is forced deep underground. the resulting buildup of pressure can cause fault lines (cracks in the earths crust) to shift. according to mark petersen, head of the u.s. geological surveys earthquake hazard mapping project, \in the past five years, the usgs has documented high shaking and damage in areas of these six states, mostly from induced earthquakes.\ what is the main, or central, idea of the passage? residents of six u.s. states have experienced an increase in earthquake activity in recent years. an increase in oil and gas drilling has caused a corresponding increase in earthquakes in six states.

Explanation:

The passage starts by noting Americans' typical association of earthquakes with California, then focuses on six states (Arkansas, Colorado, Kansas, New Mexico, Oklahoma, Texas) where increased oil - and gas - drilling has led to induced earthquakes due to wastewater disposal causing fault - line shifts. The main idea is about the link between oil and gas drilling and the rise in earthquakes in these states.

Answer:

An increase in oil and gas drilling has caused a corresponding increase in earthquakes in six states.