HELSINKI, Aug 4 (Reuters) - Finland's Metso Outotec on Wednesday reported a smaller-than-expected rise in second-quarter core earnings but said it expects market activity to improve.

The mining equipment maker said its April-June operating profit rose to 97 million euros ($115.2 million) from 89 million last year, missing the 129.5 million euros in a Refinitiv poll of analysts.

($1 = 0.8423 euros) (Reporting by Essi Lehto and Tarmo Virki, Editing by Louise Heavens)