The Proceedings of the Eighth International Conference on Creationism (2018)

Coulson, K.P. 2018. Global deposits of in situ upper Cambrian microbialites— Implications for a cohesive model of origins. In Proceedings of the Eighth International Conference on Creationism , ed. J.H. Whitmore, pp. 373–388. Pittsburgh, Pennsylvania: Creation Science Fellowship. GLOBAL DEPOSITS OF IN SITU UPPER CAMBRIAN MICROBIALITES— IMPLICATIONS FOR A COHESIVE MODEL OF ORIGINS Ken P. Coulson , San Diego Christian College, Department of Science, 200 Riverview Pkwy, Santee, CA 92071 USA, ken.coulson@sdcc.edu ABSTRACT The existence of in situ microbialites of biological origin located in upper Cambrian rocks in western Utah presents some problems for creationists as they seek to define the boundary that separates pre-Flood deposits from those that were deposited during the Flood event itself. These microbialites are extensive in nature, covering an area of at least 2600 km 2 , and are stacked one atop the other in multiple beds that span a thickness of at least 300 m, but could be as thick as several km (intercalated between wackestone wedges). Other microbialites found throughout similar upper Cambrian rocks in Nevada and California are most likely representative of those in western Utah. Upper Cambrian microbialite beds have also been described from other areas in North America that circumscribe what appears to be the ancient coast of the North American craton associated with Laurentia. A total of 24 different locations span North America starting in Newfoundland, traveling down to the NewYork area, crossing the southern United States to Texas, then moving over to the region around Utah, California and Nevada, before continuing the trail northward through Idaho, Alberta and on into the Northwest Territories of Canada. If these microbialites indeed are in situ , then they represent vast environments that require time frames greater than the one-year period of Noah’s Flood. KEY WORDS stromatolite; microbialite; pre-Flood; Flood-boundary; Cambrian; creation Copyright 2018 Creation Science Fellowship, Inc., Pittsburgh, Pennsylvania, USA www.creationicc.org 373 INTRODUCTION 1. Creationist Background and Relevance For creationists, the approximate location of the pre-Flood/Flood boundary, as well as the Flood/post-Flood boundary are important topics that have far-reaching applications for creationist model- building in general. Reasoning that rejects such a boundary (or boundaries) usually stems from a belief that the Noahic Flood of Genesis 6-9 was merely local. If, however, the Flood of Noah was global in scope, as most creationists believe, then there should exist plenty of geological evidence to support this belief. Moreover, since most creationists interpret the geological events associated with the Flood in terms of “normal, natural processes,” then the geological evidence should be subject to scientific enquiry. Starting from these assumptions and using the biblical account as a guide, most creationists therefore assume that the onset and duration of the Flood was geologically rapid and catastrophic, taking about a year from its inception to its end. Since the normal rules of science apply, the evidence for this boundary should therefore be detectable and measurable. Most creation geologists believe that the Precambrian/Cambrian boundary, or very close to this boundary, is representative of the pre-Flood/Flood boundary (Austin and Wise 1994; Dickens and Snelling 2008; Dickens 2017). Others disagree (Oard 2013), but the consensus favors this interpretation. Arguments supporting a pre-Flood/Flood boundary at the Precambrian/Cambrian boundary are quite persuasive and make sense given the kinds of processes one might assume were at work during this period. Perhaps the most persuasive argument is the wide spread existence of a surface of erosion called “the Great Unconformity.” This surface of erosion occurs at many localities around the world, and its existence is supported by both creationists and secularists alike (Austin and Wise 1994; Dickens and Snelling 2008; Peters and Gaines 2012; Dickens 2017). Another persuasive argument points to the great disparity that exists between the fossil record as it appears both below and above this boundary. Fossils, especially metazoans, are rare in Precambrian rocks, while abundant in those that belong to Cambrian time. Catastrophic burial during the Flood seems a robust explanation for the existence of almost perfectly fossilized fauna all over the world. For most creationists then, the Precambrian/Cambrian Flood boundary is an obvious choice that needs no further consideration. This paper identifies some very real challenges to this assumption. 2. Geologic Background From a secular perspective, the western continental margin of Laurentia is thought to have formed during the Late Proterozoic rifting of Rodinia. According to Miller et al. (2003, p. 58), lower Paleozoic strata of the eastern Great Basin were deposited on a collapsing carbonate platform that provided thousands of meters of accommodation space. The Cambrian/Ordovician Orr and Notch Peak Formations as well as the Ordovician House Limestone lie within these sediments in what is now southwestern Utah. Central to this discussion is the microbialite-bearing Notch Peak Formation which has been divided into three mappable members: the Hellnmaria, Red Tops and Lava Dam (Fig. 1). 3. Microbialite Definition For the purpose of this paper, the definition of Burne and Moore (1987, p. 241-242) will be used: “Microbialites are organosedimentary deposits that have accreted as a result of a benthicmicrobial community trapping and binding detrital sediment and/or forming the locus of mineral precipitation.” Caution must, however, be exercised when working with this definition due to