FACTBOX: Dolly's impact on Gulf of Mexico oil sector

(Reuters) - Tropical Storm Dolly, the first serious storm in the U.S. Gulf of Mexico this year, has shut 7.9 percent of natural gas output and nearly 5 percent of Gulf oil production.

Dolly became a hurricane Tuesday afternoon and came ashore north of Port Isabel, Texas, about midday Wednesday.

The Gulf provides 25 percent of U.S. oil output and 15 percent of U.S. natural gas production.

Following are energy industry developments so far in response to the threat from Dolly.

******************OFFSHORE PRODUCTION IMPACT******************

- Exxon Mobil Corp shut 12,000 barrels per day of liquids and 100 million cubic feet per day of natural gas.

- Anadarko Petroleum Corp. reported peak shutdown of 30,000 barrels per day of oil equivalent, but later restored 10,000.

- Apache Corp shut in 56 million cubic feet per day of natural gas production and 30,000 bpd of crude oil.

- Chevron said the storm forced "minimal" shut-in production.

- Shell, one of the largest U.S. Gulf of Mexico producers, said there was no effect on its offshore oil and gas flow but an undisclosed amount was shut onshore.

- El Paso shut down "a handful" of onshore oilfield drilling and maintenance operations with no production impact.

- U.S. Minerals Management Service said Wednesday 606 million cubic feet per day (mmcfd) of natural gas shut, 7.9 percent, up from 395 mmcfd Tuesday, and 58,122 bpd of offshore oil shut, 4.5 percent of total, down from 60,621 Tuesday.

*****************OFFSHORE PIPELINE IMPACT********************

- Williams Cos Inc said its Transco pipeline system is carrying 250 mmcfd less natural gas due to well shut-ins.

********************OFFSHORE EVACUATIONS**********************

- MMS said on Wednesday personnel have been evacuated from 62 production platforms, or 8.6 percent of 717 manned platforms in the Gulf, up from 49 Tuesday, and from eight drilling rigs, or 6.5 percent of 123 currently operating in the Gulf, up from six Tuesday.