IT major Infosys today announced acquisition of US-based oil and gas consulting firm Noah Consulting for 70 million US Dollars (approximately Rs 453.5 crore) in an all-cash deal.Noah Consulting LLC, is a provider of advanced information management consulting service for the oil and gas industry.Infosys said the acquisition is part of its strategy to bring next generation data analytics solutions to the oil and gas industry.The transaction is expected to close before the end of the third quarter of 2015-16, the company added.Meanwhile, in another acquisition, HCL Technologies Ltd has under a definitive agreement acquired a Bengaluru-based privately held engineering services firm, Concept to Silicon Systems for an undisclosed sum.