The Hydrothermal Biome: A Pre-Flood Environment

[2] argued for a pre-Flood/Flood boundary in the lower part of the Kingston Peak Formation in the East Mojave of eastern California and western Nevada. Diabase and associated evidence of contact metamorphism and rapid cooling in the Crystal Spring Formation, as well as solution pipes, chaotic bedding, dome structures, and massive precipitite production in the overlying Beck Spring Formation suggest that hydrothermal activity associated with the cooling of the diabase generated the Beck Spring sediments in pre- Flood times. The swelling of the Crystal Spring sediments by the intrusion of the hot diabase is thought to have brought the sediments at or to sea level. A shallow water status was maintained for an extended period as the shrinking of the cooling diabase was equalled by the generation of the primary dolomites of the Beck Spring Formation. The presence of these rocks in what [2] interpret as deep continental rise sediments combined with the evidence of shallow marine sediments to the west suggests that this environment was located far offshore on the edge of the continental shelf, creating landward, a several-hundred-mile wide, marine lagoon on the continental shelf. Abundant cryptalgal structures and stromatolites in East Mojave and Grand Canyon sediments suggest that the seaward portions of this lagoon may have been ideal for stromatolite growth. Sediments overlying the Beck Spring Formation contain a sequence of fossils, from stromatolites, to Ediacaran organisms, to small shelly fossils, and finally to traditional ‘Paleozoic Fauna’. This suggests that the pre-Flood continental shelf housed a spectrum of marine ecosystems from the margin landward: (a) a shallow-water, stromatolitic, hydrothermal, carbonate reef environment; b) a deep-water, sandy(?) evironment, with an Ediacaran benthos; c) a carbonate(?) environment populated with the organisms which generated the small shelly fossils; and finally d) a non-carbonate(?) muddy environment populated by the ‘Paleozoic Fauna’. The wide-spread nature of similar diabase in the Southwest suggests that the hydrothermal environment may have been at least regional in extent. The similar sequence of rocks and fossils at a number of locations worldwide suggests that the hydrothermal biome evidenced in what is now Southwestern United States may have been a widespread feature of the pre-Flood world. In this interpretation, on the first day of the Flood, the breakup of the \u27fountains of the great deep\u27 (Genesis 7:11) collapsed a portion of the distal carbonate bank onto the continental rise. The earliest Flood sediments were poured through the resultant hole in the reef, resulting in rapid and deep burial – and thus preservation – of these earliest Flood deposits. The extinction of many of the creatures of this biome (many of the stromatolite taxa, the Ediacaran Fauna, the small shelly fossils, and most of the Paleozoic Fauna) is explained by the failure to regenerate the same protective regime in post-Flood times. The few survivors from this fauna/flora (stromatolites, thermophilic bacteria) are relegated to relict localities in the present world (e.g. mid-ocean ridges, geysers, hypersaline intertidal environments)