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Hello guys! That was outside of my plans to search in such direction, however a small comment started a big discussion about the possibility to have magma melting the rocks and sealing some fossils. In fact what I was suggesting as simple "melting" seems to be a very complex process or group of processes, that I would suggest to discuss here. So it was already commented, that magma can't really melt other rocks. The temperature of magma is not high enough and it will cool down . Still we see many effects of the magma on the rocks and especially on the sediments and fossils. Here I will try to explain some, so let try to discuss it in the best scientific way . First of all - we talk for underwater sediments. Most likely the intrusion of magma happened when there was still water on the surfice. The main difference between LAVA and MAGMA - these are both the same, however the lava is a magma, that reach the surface and errupt as volcanic activity. But we don't discuss such lava. Most of the time we will see some effects of the magma, intruding near the surface . 1. First effect of the magma - high temperature. Because of the high temperature - the sediments where magma is intruding will be heated. In fact we may not see real melting of these sediments, but because of the high temperature - it will cause these sediments to undergo termal processing which is similar to ceramic production. The water will evaporate. And the clay will harden into very solid hard matterial. 2. The effect of the pressure . Because the magma will erupt from the lower layers - it is under high pressure there. If there is way to the survice it will cause volcanic erruption. It the pressure is not high enough or no such way, the molten magma will try to find any possible space and will fill it. Together with the high temperature - the magma will burn some organic materials and will fill its space. So we may see the exact copy / matrix/ of the organic material but filled and formed by the magma. 3. Chemical processes. Some minerals from the magma may reacct with water or dissolve under hither temperature with water and this may create some kind of magmatic liquid - which would be boiling water with all kind of chemical elements in it. This water may fill the gaps on the bottom, it will be heavier than the normal water and it may create a layer of sediment. 4. The evaporation of water. This is only for a case if water layer is very low and high temperature from underground to evaporate the water, causing all the sediments to form a solid crust. 5. Effects of gases. 6. Cracks - usually the magma will come near the surface through the cracks, so we can see the magma or some products created by magma to fill the cracks in the rocks. The color of such magma or magmatic liquid substances is usually red-brown or black. With all the mention here possibilities I will try to provide some examples of rocks and fossils that I found and to give some explanation, but I should tell that I am not a chemist, I am not geologist. So my explanations are weak. There should be better explanations by the specialists in this field. What is very clear for me: For some very specific rocks and fossils - I may suspect or I recognize some effects of the magma . These are not difficult to recognize. There are many hints to suggest such magmatic activity . I fully understand this is a complex problem and I don't have the background to do such scientific research, I would like to share some observations and to discuss with other participants about such effects and fossil affected by magma actions. First , I will give some examples of rocks, affected by the magma.