Deposition Deposition is the laying down of sediment carried by wind, water, or ice. Sediment. can be transported as gravel, sand, silt and clay. Rock types are indicated by the following symbols in figure A. Limestone Organiorich shale Conglomerate Basealt Sandstone Refer to Figure A for questions 1 to 6 : 1A. The oldest layer is a. limestone. (b.) basalt. c. sandstone. d. shale. 2A. The layer in question 1 A probably formed a. during a non-explosive eruption. b. during the formation of a batholith. c. during a river flood incident. d. on high mountains. 3A. The next oldest layer is a. shale. b. limestone. (c) conglomerate. d. basalt. 4A. The change in layer 3 to layer 4 was most likely produced by a. the rising of the land. b. a flash fiood. c. volcanic activity. d. the introduction of a moving river. 5A. The shale in layer 7 indicates a. this area was part of a floodplain. b. this area was part of a fast moving river. c. an end of volcanic activity. d. an end of glaciation. 6A. The layers in figure A a. have always been above sea level. b. have never been above sea level. c. formerly were above sea level, but are now below. d. formerly were below sea level, but are now above..