* H1 net income up 15 pct y/y to $217 mln
* Drilling output up 6 pct in H1
MOSCOW, Aug 29 (Reuters) - Russia's biggest oilfield services company Eurasia Drilling said on Thursday its first-half net income rose 15 percent thanks to increased complex drilling at depleted fields in the world's top oil producing nation.
Eurasia Drilling, created last decade after Russia's top non-state producer Lukoil spun off its services business, said the January-June net profit rose to $217 million.
Horizontal drilling rose almost 20 percent in the first half to 492,000 metres, while total drilling output edged up 6 percent to 3 million metres.
Horizontal drilling is technically more challenging and more expensive than conventional vertical drilling but taps hydrocarbon reservoirs more efficiently and yields better flows.
Companies use the method to increase productivity at mature fields which now account for more than 80 percent of Russia's total oil resource base.
"As we anticipated, the demand for more complex drilling continues to be strong as we help our customers to achieve their production targets," EDC's Chief Executive Officer Alexander Djaparidze said in a statement.
The group's revenues increased almost 8 percent to $1.7 billion in the January-June period, while earnings before interest, taxation, depreciation and amortisation (EBITDA) rose 17 percent to $441 million.