Necessity of geological heritage preservation for resolving geological question (exemplified by a reference sectionof the Kurgashlinsky Formation of the Early Vendian in the South Urals).
N.N. Kopylova
All-Russian Geological Institute (VSEGEI), Sredniy str., 78, Saint-Petersburg, Russia  From the history of problem developing.
L. Agassits studied rare-pebble conglomerates or boulder loams (tills) in Europe in the XIXth century. He advanced a hypothesis on cover glaciation (1840). This idea is prevailing till now.
In 1946 1956, in the USSR the I.G. Pidoplichkos monograph "On the glacial period" was published. In it, paleo-zoological, paleo-botanical, archeological and geological questions of the Quaternary (glacial) period were examined. The scientist came to the conclusion on the absence of cover glaciation in Europe and Western Siberia. P.P. Generalov (1981 1983) came to the same conclusion for the Western Siberia. He confirmed that terminal-moraine ridges have tectonic genesis. V.G. Chuvardinsky proves the inaccuracy of the main provisions of glacial theory on the basis of geological-geomorphological studies in the Karelia-Kola Region and in other regions of Northern Russia (1970-2004). Norwegian scientists (Lauritzeen S.E. et al. , 1995)
determined the non-glacial conditions in the immediate proximity from the center of Scandinavian glaciation 150 71 thousand years ago. Results of the Swedish and American scientists' modeling (Naslund J.O., Rodhe L. et al, 2003) indicate the absence of ice in the Eastern Kola Peninsula up to 70,000 years ago. These conclusions do not contradict D.Yu. BolshiyanoVs conceptions (2005) on the evolution of passive glaciation in the Pleistocene, which did not cause considerable accumulative and exarative relief forms formation. Thus, active glacial shields, which occupied the Barents and Kara seas, based on available geological materials and recent glaciological conceptions, could not exist. Geologists distinguished rocks similar to rare-pebble conglomerates in the ancient complexes, which were named tillites. Thus, the conception on repetitive continental glaciations during the whole Earth's history spread. The Early Vendian cover glaciation was named Varanger by O. duelling (1942), Lipaliy by G.F. Lungersgaisen (1957) and Lapland by N.M. Chumakov (1974).
Evidences of a reference section of the Kurgashlinsky Formation of the Early Vendian in the South Urals.
The author studied rare-pebble conglomerates of the Kurgashlinsky Formation of the Early Vendian in 2005 - 2007 in the Baynozarovo village region (South Urals). N.M. Chumakov (1998) referred these rocks to glacial sediments, tilloids. In rare-pebble conglomerates, there are fragments of dolomites, quartzite-like sandstones, flint and rocks like host matrix.
The author found borders on the edges of some fragments, which are the evidence of temperature gradient between them and the matrix. For the first time, tufogenic components in the primary sediments and changes of clarified rock parts with deep fluids were found. Large fragments and microlites split in situ are of particular interest. Dispersed inclusions are either pseudo-boulders or supplied from underlying formations by fluid flows.
Cloos H. (1941) named analogous rocks tuffisites. Similar rocks are also named diamictites (Byakov, 2005). However, they differ from rare-pebble conglomerates of the Kurgashlinsky Formation. N.N. Kopylova (2001-2008) suggested more common term, mixtites. Also an open for discussion variant of their genesis, the result of reactionary interaction of deep fluids and non-lithified sediments during tectono-magmatic activity was suggested. Recently, probably a universal name appeared in the literature, fluidizates. Properties of texture, structure and mineral composition are attributed to the diagnostic features of fluidizates. Endogenous dolomites and dolomite puddings often make associations with fluidizates. Formation temperature of fluidizates is determined in vacuum decryptograph with thermobarogeochemical study of melt inclusions in grains of obsidians, dolomites, apatite and graphite crystals. Values from 620°to 1,115*0 were obtained (Yakobson etal., 1999). The same problem of conglomerates and pseudo-conglomerates obtains special significance for exploration and estimation of diamond objects in the Urals. The first finds of diamonds are known in the Vendian sediments {Kazantsevetal., 1985; Yakobson etal., 2004). For maintenance of present mineral raw needs without damage for the next generations, it is necessary to develop the prediction of the fields. It must be based on the multilateral study and theoretical basis of geological presupposition of objects forming taking into account revealing of new data.
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