The problem was that (gas) was locked in shale, the extremely dense layer of rock under Dallas and Forth Worth.

FORBES: Move up http://i.forbesimg.com t Move down

The entire city of Fort Worth sits over a gas dense layer of black rock called the Barnett Shale that only recently became possible to access.

NPR: Drilling for Gas in Dallas-Fort Worth

This is a fundamental change in the business equation, enabling much more robust investment in this layer of wireless infrastructure throughout dense urban environments.

FORBES: Wi-Fi's Task For 2011: Making Networks IPad-Friendly

Odzala is characterized by a rich variety of habitats, including primary rain forest with a closed canopy (e.g. with Entandrophragma utile, E. candollei and E. cylindricum) and open understorey layer, forests dominated by dense formations of Marantaceae, forest clearings and savannas on the hilltops (e.g. with Hymenocardia acida, Annona arenaria or Hyparrhenia diplandra).

UNESCO: Biosphere Reserve Information