In the last trading session, U.S. stocks rose on the strength in the energy sector after the Organization of the Petroleum Exporting Countries (OPEC) unexpectedly agreed to curb its oil production for the first time in eight years. Among the top ETFs, investors saw (SPY Quick QuoteSPY - Free Report) gain 0.5%, (DIA Quick QuoteDIA - Free Report) rise 0.6% and (QQQ Quick QuoteQQQ - Free Report) move higher by 0.2% on the day.

Two more specialized ETFs are worth noting as both saw trading volume that was far outside of normal. In fact, both these funds experienced volume levels that were more than double their average for the most recent trading session. This could make these ETFs the ones to watch out for in the days ahead to see if this trend of extra-interest continues:

(IXN Quick QuoteIXN - Free Report) : Volume 4.50 times average

This technology ETF was in focus yesterday as more than 140,000 shares moved hands compared with an average of roughly 33,000 shares a day. We also saw some price movement as IXN added nearly 0.6% in the last session.

The big move was largely the result of the tech boom on improving industry fundamentals, investors’ drive for cheaper valuation and renewed focus on beaten down growth stocks. In the past one-month period, IYK was up 16.9%.

(PXJ Quick QuotePXJ - Free Report) : Volume 3.88 times average

This energy ETF was under the microscope yesterday as around 56,000 shares moved hands. This compares with an average trading day of around 15,000 shares and came as PXJ gained 5.8% in the session.

The movement can largely be blamed on OPEC’s surprise move that sent oil price higher and can have a big impact on energy stocks like what we find in this ETF portfolio. PXJ was down 6.6% in the past one month and has a Zacks ETF Rank of 4 or ‘Sell’ rating with a High risk outlook.

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