Significant

Encana Corp. on Thursday struck a C$2.18 billion joint venture (JV) agreement to explore and develop close to half a million acres of its leasehold in the Duvernay Shale with a subsidiary of PetroChina International Ltd.

Marathon Oil Corp.’s $5.2 billion capital, investment and exploration budget for 2013 is about 65% targeted toward liquids-rich areas, particularly the Eagle Ford Shale of South Texas.

WPX Energy Inc. announced a net loss of $64 million for 3Q2012 on Thursday, but it also reported significant growth in oil production in the Bakken Shale and tripled natural gas production in the Marcellus.

Environmental groups on Tuesday filed a lawsuit in California claiming that state regulators had failed to “consider or evaluate” the risks of hydraulic fracturing (fracking) as required by the California Environmental Quality Act (CEQA).

Despite weak prices, there is “significant upside optionality” to natural gas, according to a Credit Suisse analyst.

Seneca Resources Corp. is proceeding with drilling operations in the Marcellus and Utica shales, and has established positions in oil fields in Kansas and California, the National Fuel Gas Co. (NFG) subsidiary said Thursday.

Environmental questions and high costs for water have created a big headache for unconventional oil and gas producers, but it won’t take long before those problems are turned into opportunities for other businesses, according to industry executives.

With efforts by pipelines and state regulators, the Pipeline and Hazardous Safety Administration (PHMSA) said it anticipates a significant reduction in pipeline-related deaths or major injuries over the next four years.

Continental Resources Inc.’s shareholders have approved the company’s purchase of Wheatland Oil Inc.’s core assets in the Bakken Shale, a stock deal valued at about $276 million.