With last Friday's nosedive and today's horrific sell-off, the Dow Jones Industrial Average (DJINDICES:^DJI) seems dead-set on recording its worst losses since June. As of 2:40 p.m. EDT, the Dow has fallen 219 points, or 1.64%, with nearly every member of the index in the red. If today's trend keeps up, the Dow is set to mark one of its worst days of the year. A few stocks have managed to eke out gains, but several horrible earnings reports have put pressure on all sectors. Let's see what's behind this plunge.

Swimming in fear
It's fear driving the markets today: The market's best gauge of fear -- the CBOE Volatility Index (VOLATILITYINDICES:^VIX) -- has jumped 11% to reach its highest levels since early August. Fears over Spain's debt haven't subsided, and uncertainty has surged with the U.S. election almost here, but this earnings season's prophesied hammer has fallen the hardest today.

DuPont (NYSE:DD) has sent the biggest shockwaves through the market today, plunging more than 8.7% so far. The company reported third-quarter earnings that fell 98% from a year ago and badly missed expectations; even without one-time items and restructuring costs included, EPS still missed estimates. Due in part to the shaky economy, the company cut its full-year guidance significantly.

Following the earnings trend, 3M (NYSE:MMM) met expectations -- but also reduced full-year guidance, sending shares of the company falling 3.6% so far. United Technologies (NYSE:UTX) rounded out the earnings day, missing on revenue expectations despite smashing earnings projections. The conglomerate has fared better than most companies for the day so far, however, with shares only losing 0.7%.

Wait out the storm
The Dow also slammed the energy sector today, with oil giants Exxon Mobil (NYSE:XOM) and Chevron (NYSE:CVX) both placing among the worst index laggards with losses of 1.87% and 2.6%, respectively. While a pair of tech stocks managed to squeeze out gains for the day, the Dow has simply thrown up its hands and fallen into an earnings-miss-induced free fall. Investors can only wait this storm out and hope for a brighter tomorrow.

Dan Carroll has no positions in the stocks mentioned above. The Motley Fool owns shares of ExxonMobil. Motley Fool newsletter services recommend Chevron and 3M Company. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.