I am not aware of any studies on this topic. You must consider, however, that Assomineraria, which represents companies operating in the mining and oil sector in Italy, has only 150 members. These include not only companies, Italian and foreign, operating in the exploration and production of minerals and hydrocarbons in Italy, but also companies providing goods and services for the oil sector.
There are a number of papers concerning the CSR in the extraction industry. A quick search among the ones I read revealed the following but incomplete list, hope this helps you out a little.