Naphtha cracks that had a drastic fall last week, have seen a marginal improvement. The beginning of the week saw naphtha prices dip to a four-session low while cracks ended higher than levels seen in the previous week. This week’s marginal rise in naphtha cracks that were at four-month lows last week, reflected weak market sentiment. Gasoline cracks were at a 2-1/2 month low as bad weather in the West dampened sellers' sentiment, weighing down the Asian market. US gasoline stocks surged 6.15 mln barrels to 236.23 mln barrels in the week ended January 28, the highest level since 1993. Cold weather in parts of the US has curtailed long-distance driving.