MarkWest Energy Partners (MWE) spikes as MPLX buys

MarkWest Energy Partners LP

was soaring 9.8% Monday to $65.59 after it said it was being acquired by MPLX LP in a deal valued at $15.8 billion, which would create a master limited crude-oil and natural-gas giant. Share volume was 528,000, compared to an all-day average of 178,000