We don't think so, at least not in the same way that the earth does. The atmospheres are so massive that the farther in you go, the hotter they get. The chemistry becomes very exotic because the temperature, density and pressure increase as you get deeper into the core.

We think that each of the outer planets has a rocky core about 2 - 10 times the mass of the earth, but under the typical pressures and temperatures, the rocky material is actually a very dense, molten liquid. In the case of Jupiter, the central temperatures are near 60,000 degrees kelvin! The atmospheres probably increase rather smoothly in density, from the density of the earth's atmosphere and well past the density of lead without the appearance of a boundary occurring. A boundary will be reached near the core where the composition changes over from the atmospheric constituents to the heavier elements in the 'rocky' material, but this boundary would be as reachable as the center of our own planet and its 'iron-nickel' core.

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