Ecclesiastes 12:6 Or ever the silver cord be loosed, or the golden bowl be broken, or the pitcher be broken at the fountain, or the wheel broken at the cistern.
Ecclesiastes 12:7 Then shall the dust return to the earth as it was: and the spirit shall return unto God who gave it.
Ecclesiastes 3:19 For that which befalleth the sons of men befalleth beasts; even one thing befalleth them: as the one dieth, so dieth the other; yea, they have all one breath; so that a man hath no preeminence above a beast: for all is vanity.
Ecclesiastes 3:20 All go unto one place; all are of the dust, and all turn to dust again.
Ecclesiastes 3:21 Who knoweth the spirit of man that goeth upward, and the spirit of the beast that goeth downward to the earth?
Since the body returns to the dust, it really doesnt matter how that happens, whether by decomposition, burning, or even drowning and decomposing under water. The spirit instantly returns to God at death and the body itself will never be ressurected. A flesh body has only in special cases been ressurected.