That said, natural gas exploration and development company Chesapeake Energy (NYSE:CHK) is a fairly recent addition worth noting.

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Upstream activities include oil and natural gas exploration, field development and production.

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Concho Resources Inc. (Concho) is an independent oil and natural gas company engaged in the acquisition, development and exploration of oil and natural gas properties.

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Chesapeake Energy Corp. is an independent oil and gas company engaged in the development, exploration, acquisition and production of onshore natural gas and oil reserves.

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In Iraq, Oil and Natural Gas Corp. signed a number of contracts prior to the war, including exploration and development deals in the south as well as in other fields.

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The boom in natural gas development should also stimulate the local economies and employment incomes of counties and states where drilling, exploration and transportation are centered.

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