You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
2008_Sichuan_earthquake

Context:
In 2002, Chinese geologist Chen Xuezhong published a Seismic Risk Analysis study in which he came to the conclusion that beginning with 2003, attention should be paid to the possibility of an earthquake with a magnitude of over 7.0 occurring in Sichuan region. He based his study on statistical correlation. That Sichuan is a seismically active area has been discussed for years prior to the quake, though few studies point to a specific date and time.

Question:
In what year did Chen Xuezhong publish an earthquake study?

2002