This segment is from Tuesday's edition of, "Digging for Value", where sector analysts Joel South and Taylor Muckerman discuss energy & materials news with host, Alison Southwick. The twice-weekly show can be viewed on Tuesdays & Thursdays. It can also be found on Twitter, along with our extended coverage of the energy & materials sectors @TMFEnergy .

Despite what many have thought for months, the margin expansion that petrochemical companies like LyondellBasell Industries NV (LYB -5.79%) and Westlake Chemical Corp (WLK -6.29%) have been enjoying is not over just yet. As ethane prices remain low, with the prospects of falling even further, expansion plans at both companies are well under way along the Gulf Coast region. If the status quo stands pat, these expansions could mean significant profits are en route for 2014. 

These ethane prices didn't just appear out of thin air, however. Much of the praise is lauded upon the natural gas producers, but pipeline companies like Kinder Morgan's El Paso Pipeline Partners (EPB), MarkWest Energy Partners (NYSE: MWE) and Sunoco Logistics Partners (NYSE: SXL) have been providing access points across the eastern United States. This availability has been influential in the recent growth out of the Marcellus region. 

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