10 research outputs found
The Ice Age: It Really Was Short
The Ice Age and its ending have been dated based on uniformitarian thinking with 14C, dendrochronology, varves and many tens of other dating methods. These dating methods have been correlated to each other, and basically have been fitted to the uniformitarian interpretation of the geological column.
The methods, which are stated to be more important, have been more carefully studied. These methods are sometimes even labeled “absolute,” and are the main methods for correlation and especially dating of the last stages of the Ice Age. Fieldwork on Swedish laminated clays called (yearly) varves show climbing ripples and water escape structures, hence showing that the “varves” cannot be yearly but must instead sometimes even have been catastrophically deposited. Also, the “absolute” correlation of 14C dates and dendrochronology has been shown to be faulty, and fits a short biblical chronology very well.
Glacigenic erosional and depositional landforms, for example, extent and stratigraphy of tills, moraine forms, depth of glacial erosion, and glaciofluvial sediments, all indicate one single short Ice Age
Diamictites: Ice-Ages or Gravity Flows?
A literature study directed mainly on sedimentological/erosional structures, combined with limited field work, give good grounds for rejecting the normal ice-age interpretation for relics from Pre-Pleistocene ice-ages , in favour of an interpretation as (mainly) different kinds of gravity flows. The long ages held by uniformitarian geologists for the formation of these structures are therefore no longer necessary, and the data instead point to an interpretation favouring a short timescale.
Deposits from especially dense gravity flows can look very similar to till. Also, many structures formed in gravity flows can look very similar to structures formed or influenced by glaciers . Some examples are till fabric, the occurrence of erratics, polished and striated stones and bedrock, the occurence of dropstones and periglacial phenomena.
The following regularly occuring structures are features of Pre-Pleistocene till ites which are never or rarely formed by glaciers, but are usually formed by gravity flows: A) the small extension and great depth of the tillites , B) the small size of erratics, C) stones pressed down in the underlying material, D-E) sorting of stones and erratics, F) channels eroded by water below the tillites , G) layers of dolomite and coal in close connection with the tillites , H) boulder pavements, I) no weathered till or soil profiles between different tillite layers , and J) the geographical occurence and extension of late Precambrian tillites .
All the above speaks against the interpretation of diamictites as glacial deposits, but favours gravity flows
The origin of upper Precambrian diamictites, northern Norway: a case study applicable to diamictites in general
Upper Precambrian diamictites in Varangerfjorden (northern Norway) have been examined for evidence of origin, whether
glaciogenic, gravity flow or polygenetic. Studies of geomorphology, sedimentology and surface microtextures on quartz
sand grains are integrated to provide multiple pieces of evidence for the geological agents responsible for the origin of
the diamictites. The documented sedimentary and erosional structures, formerly interpreted in a glaciogenic context (e.g.,
diamict structure, pavements and striations) have been reanalysed. Field and laboratory data demonstrate that, contrary
to conclusions reached in many earlier studies, the diamictites and adjacent deposits did not originate from glaciogenic
processes. Evidence from macrostructures may occasionally be equivocal or can be interpreted as representing reworked,
glacially derived material. Evidence from surface microtextures, from outcrops which are believed to exhibit the most unequivocal
signs for glaciation, display no imprint at all of glaciogenic processes, and a multicyclical origin of the deposits
can be demonstrated. The geological context implies (and no geological data contradict this) an origin by gravity flows,
possibly in a submarine fan environment. This reinterpretation of the diamictites in northern Norway may imply that the
palaeoclimatological hypothesis of a deep frozen earth during parts of the Neoproterozoic has to be revised
Tephrochronology : Methodology and correlations, Antarctic Peninsula Area
Abstract Methods for tephrochronology are evaluated, in the following way: Lake sediments <500 years old from three small Antarctic lakes were analysed for identification of tephras. Subsamples were analysed for a) grain size, and identification and concentration of volcanogenic grains, b) identification of tephra horizons, c) element abundance by EPMA WDS/EDS and LA-ICP-MS, and d) possible correlations between lakes and volcanoes. Volcanogenic minerals and shards were found all through the sediment cores in all three lakes, in different abundances. A high background population of volcanogenic mineral grains, in all samples, made the identification of tephra horizons difficult, and shards could only be distinguished by certainty after chemical analysis of elements. The tephra layers commonly could not be seen by the naked eye, and, hence they are regarded as cryptotephras. Because of the small size of recent eruptions in the research area, and the travel distance of ash, most shards are small and difficult to analyse. Nine possible tephra horizons have been recorded in the three lakes, and preliminary correlations have been made. But because of analytical problems, the proposed correlations between the lakes and possible volcanic sources are preliminary
Tephrochronology : Methodology and correlations, Antarctic Peninsula Area
Abstract Methods for tephrochronology are evaluated, in the following way: Lake sediments <500 years old from three small Antarctic lakes were analysed for identification of tephras. Subsamples were analysed for a) grain size, and identification and concentration of volcanogenic grains, b) identification of tephra horizons, c) element abundance by EPMA WDS/EDS and LA-ICP-MS, and d) possible correlations between lakes and volcanoes. Volcanogenic minerals and shards were found all through the sediment cores in all three lakes, in different abundances. A high background population of volcanogenic mineral grains, in all samples, made the identification of tephra horizons difficult, and shards could only be distinguished by certainty after chemical analysis of elements. The tephra layers commonly could not be seen by the naked eye, and, hence they are regarded as cryptotephras. Because of the small size of recent eruptions in the research area, and the travel distance of ash, most shards are small and difficult to analyse. Nine possible tephra horizons have been recorded in the three lakes, and preliminary correlations have been made. But because of analytical problems, the proposed correlations between the lakes and possible volcanic sources are preliminary
Tephrochronology : Methodology and correlations, Antarctic Peninsula Area
Abstract Methods for tephrochronology are evaluated, in the following way: Lake sediments <500 years old from three small Antarctic lakes were analysed for identification of tephras. Subsamples were analysed for a) grain size, and identification and concentration of volcanogenic grains, b) identification of tephra horizons, c) element abundance by EPMA WDS/EDS and LA-ICP-MS, and d) possible correlations between lakes and volcanoes. Volcanogenic minerals and shards were found all through the sediment cores in all three lakes, in different abundances. A high background population of volcanogenic mineral grains, in all samples, made the identification of tephra horizons difficult, and shards could only be distinguished by certainty after chemical analysis of elements. The tephra layers commonly could not be seen by the naked eye, and, hence they are regarded as cryptotephras. Because of the small size of recent eruptions in the research area, and the travel distance of ash, most shards are small and difficult to analyse. Nine possible tephra horizons have been recorded in the three lakes, and preliminary correlations have been made. But because of analytical problems, the proposed correlations between the lakes and possible volcanic sources are preliminary
Field evidence suggests that the Palaeoproterozoic Gowganda Formation in Canada is non-glacial in origin
During more than a century since its original identification, the Gowganda Formation in Ontario (Canada) has gradually been reinterpreted from representing mainly subglacial tillites to secondary gravity flow and glaciomarine deposits. The main pieces of geological evidence advanced in favour of glaciation in recent articles are outsized clasts that have been interpreted as dropstones and patches of diamictites in a single small-sized area at Cobalt which is still interpreted as displaying subglacial basal tillites. The present research considers field evidence in the Gowganda Formation in the light of more recent work on gravity flows linked to tectonics. Detailed studies have demonstrated that the clasts which are interpreted to be dropstones rarely penetrate laminae and are commonly draped by sediments the appearance of which is similar to lonestones in gravity flows. The “subglacial area” at Cobalt displays evidence of tectonics and gravity flows, which can be traced from the underlying bedrock, and then further in the overlying sequence of diamictites and rhythmites. The sum of geological features displays appearances at odds with a primary glaciogenic origin, and there is no unequivocal evidence present of glaciation. The data indicate deposition by non-glaciogenic gravity flows, including cohesive debris flows for the more compact units, probably triggered by tectonic displacements
Patterns, processes and models – an analytical review of current ambiguous interpretations of the evidence for pre-Pleistocene glaciations
Models (paradigms) and former interpretations have often been presupposed when conducting field research. In the 19th century diamictites were for the first time interpreted to have originated from ancient glaciations. These interpretations have to a large part prevailed in the geological community, although there has been much progress in the areas of sedimentology, glaciology and physical geography. The present work is an effort to find criteria which most clearly discriminate between geological features produced by different processes, mainly glaciation and mass flow, the latter predominantly sediment gravity flows. Geological features which have been interpreted to have formed by glaciation throughout pre-Pleistocene Earth history are compared to similar-appearing geological features formed by mass flow and tectonics, so as to uncover variations in the appearance between features resulting from these different processes. The starting point for this comparison is documentation of the appearance of Quaternary products of erosion and deposition, in order to discern the origin of older formations. It is shown that the appearance and origin of pavements, dropstones, valleys, small-scale landforms, surface microtextures and most other geological features may in some cases be equivocal, but in others the details are indicative of the process which generated the feature. Detailed geological field data which have been compiled by geologists from outcrops of pre-Pleistocene strata, more often than is considered in most papers, commonly point to a mass flow origin, mainly a sediment gravity flow origin, rather than a glaciogenic origin. A process of multiple working hypotheses or interpretations is therefore advocated, based mainly on a comparison of the appearance of features formed by different geological processes documented from different research disciplines. Instead of starting with current interpretations or models, this multiple working hypothesis or methodology helps to avoid confirmation bias and jumping to conclusions
Reconsidering the glaciogenic origin of Gondwana diamictites of the Dwyka Group, South Africa
The Gondwana Late Palaeozoic Ice Age is probably best represented by the Dwyka Group in South Africa. Striated and grooved surfaces or pavements are commonly considered to have formed subglacially, as are diamictites which have been interpreted as in-situ or reworked tillites. These interpretations were tested by investigation of outcrops in formerly well-studied areas, throughout South Africa. Detailed analyses have focused on striated surfaces/pavements and surface microtextures on quartz sand grains in diamictites. The sedimentological context of four pavements, interpreter to be glaciogenic, display features commonly associated with sediment gravity flows, rather than glaciation. A total of 4,271 quartz sand grains were subsampled from outcrops that are considered mainly to be tillites formed by Continental glaciation. These grains, analysed by SEM, do not demonstrate the characteristic surface microtexture combinations of fracturing and irregular abrasion associated with Quaternary glacial deposits, but mainly a mix of surface microtextures associated with multicyclical grains. The Dwyka Group diamictites warrant reinterpretation as non-glacial sediment gravity flow deposits