Complex sentence: The (LGGE) in Grenoble, France, built a shallow EM drill, built in 1976-1977, based on information provided by John Rand and Henri Rufli, and building on their experience earlier in the decade.
Split into simpler sentences: The (LGGE) in Grenoble, France, built a shallow EM drill in 1976-1977. The design was based on information provided by John Rand and Henri Rufli, and built on their experience earlier in the decade.