Pioneer Natural Resources Co. (NYSE: PXD), Dallas, sold $425 million of 10-year unsecured senior notes, with a coupon rate of 9.625%. The notes are unconditionally guaranteed by Pioneer Natural Resources USA Inc., a subsidiary of the Dallas independent producer. Pioneer will use proceeds to reduce its bank debt to an estimated $411.5 million. Credit Suisse First Boston, Banc of America Securities LLC and Chase Securities Inc. arranged the debt offering. It followed commitments from Bank of America, Credit Suisse First Boston and Chase Manhattan Bank for a new, fully underwritten five-year $600-million senior credit line to replace its current facility. Led by Chase Bank of Texas, a group of banks raised the threshold of Houston Exploration Co.'s (NYSE: THX) bank credit facility by 20% to $210 million from $175 million. The increase reflects the growth of the Houston independent's reserve base, its improved credit profile and a stronger commodity price outlook, Houston Exploration reported. It came as Keyspan Energy Corp. (NYSE: KSP), Brooklyn, N.Y., converted $80 million of debt into Houston Exploration equity, reducing the independent's debt to $279 million, or 48% of book capitalization. Houston Exploration issued 5,085,177 new common shares as a result of the conversion, bringing its total number of shares outstanding to 29,008,797 and leaving KeySpan with a 70.3% equity interest. InterOil Corp. (Canadian Venture: INOL.U), Toronto, will begin to construct an oil refinery in Papua New Guinea, now that the company will receive the final US$85 million of financing from the Overseas Private Investment Corp. OPIC directors approved a debt facility which, with InterOil's cash, provides US$122 million of financing to complete the installation. InterOil contributed the balance of the project's estimated US$170-million cost as equipment and assets that it already owned. Oceaneering International Inc. (NYSE: OII), Houston, entered into a four-year, $50-million term loan agreement with Wells Fargo Bank (Texas), HSBC Bank USA, The Bank of Tokyo-Mitsubishi Ltd. and The Fuji Bank Ltd. Wells Fargo acted as agent. The service company to offshore oil will use the money for general corporate purposes, including to partially fund construction of the Ocean Legend, a mobile offshore production unit. The new term loan agreement contains similar restrictive maintenance covenants as the company's existing indebtedness relative to the level of debt to total capitalization, fixed charge coverages and minimum net worth. The term loan of $50 million provides the company with medium-term capital at a favorable cost, said Marvin J. Migura, an Oceaneering senior vice president and its chief financial officer. "Coupled with our existing $100 million of long-term debt and $80-million revolving credit facility, it preserves our flexibility to fund additional growth. In combination with Oceaneering's strong cash flow, we believe these arrangements will allow us to take advantage of almost any expansion opportunity. Ultra Petroleum (Toronto: UP), Houston, lined up a new $40-million senior credit facility with Bank One Texas. The credit line provides for an initial $18-million borrowing base, up from $12 million under the independent's previous credit facility. The new facility will reduce Ultra's cost of borrowing by at least 200 basis points, the company said. First Reserve Corp., Greenwich, Conn., made a further investment in Destiny Resource Services Corp. (Toronto: DSC), Calgary, with a C$2.8-million private placement. The private equity firm can convert the debt to Destiny common stock at a price of C50 cents per share if the oilfield service company does not repay the loan by Sept. 29. Destiny will use the money to supplement working capital for anticipated increased activity this spring and summer. It also intends to proceed with a rights offering to shareholders to raise money to repay the debt. Under the offering's proposed terms, each shareholder of record will receive one right per share. Four rights will entitle the holder to purchase an additional Destiny common share for C50 cents. The company's two largest shareholders, First Reserve and Destiny president Adrian Erickson, hold approximately 55% of its issued and outstanding shares. Along with all directors and inside investors, they intend to fully exercise their rights, the company said. United Heritage Corp. (Nasdaq: UHCP), Cleburne, Texas, received a $2-million credit facility from First Savings Bank of Arlington, Texas, to implement the independent's first-phase oil and gas production plan. The one-year revolving line of credit has a renewal option and a nationally competitive interest rate. It coincides with a $3-million equity financing that United Heritage is arranging with Atlantis Capital Group LLC of Los Angeles, which represents the largest debt and equity financing it has undertaken so far.