Complex sentence: New hydrocarbon production areas have been opened as hydraulic fracturing stimulating techniques have been combined with more recent advances in drilling complex wells that can extend deep vertical wells that are many hundreds or thousands of metres below ground, into unconventional reservoirs through horizontal drilling of directional sections.
Split into simpler sentences: New hydrocarbon production areas have been opened as hydraulic fracturing stimulating techniques are coupled with more recent advances in horizontal drilling. Complex wells that are many hundreds or thousands of metres below ground are extended even further through drilling of horizontal or directional sections.