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Geokniga-Grosvald-Mg-Oledenenie ISSN 0130–3686 ИНСТИТУТ ГЕОГРАФИИ РОССИЙСКОЙ АКАДЕМИИ НАУК ГЛЯЦИОЛОГИЧЕСКАЯ АССОЦИАЦИЯ ИЗДАТЕЛЬСТВО «НАУКА» МАТЕРИАЛЫ ГЛЯЦИОЛОГИЧЕСКИХ ИССЛЕДОВАНИЙ ВЫПУСК 106 DATA OF GLACIOLOGICAL STUDIES PUBLICATION 106 Москва Апрель 2009 Слово редактора В настоящем выпуске «Материалов гляциологи- древнего оледенения невозможно, как невозможно ческих исследований» мы посмертно публикуем пока безоговорочно отдать предпочтение какой-либо работу М.Г. Гросвальда «Оледенение Русского Севера из них. Впереди еще десятилетия полевых и лабора- и Северо-Востока в эпоху последнего великого похо- торных исследований, прежде чем мы приблизимся к лодания». В этой книге Михаил Григорьевич продол- установлению истины. жил разработку своей концепции, согласно которой, Концепция М.Г. Гросвальда логична и хорошо последняя ледниковая система, существовавшая на обоснована. Она показывает возможное развитие при- территории Евразии почти сто тысяч лет (между роды Евразии в последние сто тысяч лет и, безуслов- 110—115 и 8—10 тыс. лет назад), в периоды своего но, имеет право на существование. Эта концепция максимального развития представляла собой сплош- была принята за основу при создании палеогеографи- ной Евразийский покров. Он состоял из Скандинав- ческого раздела Атласа снежно-ледовых ресурсов мира ского, Баренцево-Карского, Восточно-Сибирского, (1997) и оказалась очень уместной в этом монографи- Берингийского и Охотского ледниковых щитов и ческом произведении. Изучение следов древнего оле- объединявших их шельфовых ледников, которые денения на базе подхода М.Г. Гросвальда позволило простирались вплоть до Северного полюса и далее. ему с группой единомышленников создать серию Публикуемую концепцию мы называем макси- карт, показывающих возможное развитие оледенения мальной, и она существенно расходится с позицией в плейстоцене в разных регионах земного шара. многих палеогеографов, рисующих для этой эпохи Предлагаемая читателям последняя книга более скромные размеры оледенения. Эти ученые не Гросвальда, как и все предыдущие, написана с поле- соглашаются с суждением М.Г. Гросвальда и приво- мическим задором. Она вся проникнута творческой дят ряд аргументов, не укладывающихся в его схему. дискуссией, весьма логичной по своей сути. И пусть Особенно обширные работы противостоящей группы не все положения предлагаемой позиции еще окон- ученых были проведены в последние десять лет в чательно доказаны, но они логично увязаны друг с рамках международной программы QUEEN. Мне другом и, в конечном счете, дают целостное впечат- приходилось заседать в руководящем комитете этой ление о возможном развитии природы Евразии. программы и обсуждать в течение ряда лет текущие Конечно, говорить об окончательном утвержде- результаты и планы этих исследований. Должен под- нии этой или альтернативных гипотез еще рано. черкнуть, что эта группа ученых выполнила обширные Пройдет немало десятилетий, которые принесут полевые работы по изучению древних отложений, новые материалы и новые методы их исследований, особенно по определению их абсолютного возраста. прежде чем четвертичная история нашей планеты Но полученные результаты не показались Михаилу станет, наконец, понятна. Пока же любая точка Григорьевичу убедительными, и в настоящей работе зрения на эту историю остается в рамках отдельных он приводит новые, порою очень строгие аргументы гипотез и концепций. Ценность концепции М.Г. Грос- в обоснование своей максимальной модели послед- вальда — в ее стройности и комплексных доказатель- него евразийского оледенения. ствах, не противоречащих природе рассмотренных Концепция Михаила Григорьевича основывает- явлений. ся на комплексе взаимосвязанных доказательств и не Михаил Григорьевич работал над этой книгой в противоречит общей картине развития природы в течение нескольких последних лет. Он дописал ее четвертичном периоде. Более того, она, пожалуй, почти до конца, и все же в конце текста приходится единственная, где следы древнего рельефа и оледене- поставить многоточие. Позиция Гросвальда имеет ния исследуются с точки зрения существовавшего противников больше, чем сторонников. И все же тогда климата и сопровождаются компьютерным хочется верить, что найдутся ученые сменяющего нас моделированием с учетом всей суммы наших знаний поколения, которые продолжат исследование, так о природе и развитии этих территорий. Конечно, блестяще выполненное в течение почти полувека примирить эту гипотезу с другими исследованиями Михаилом Григорьевичем Гросвальдом. академик В.М. Котляков М.Г. Гросвальд Оледенение Русского Севера и Северо-Востока в эпоху последнего великого похолодания M.G. Grosswald Ice sheets in the Russian North and North-East during the last Great Chill УДК 910.4.5551.32-33:551,8 Ответственный редактор академик В.М. Котляков Рецензенты: доктор географических наук, профессор Б.И. Втюрин доктор географических наук В.Л. Суходровский В настоящей работе суммированы данные о ледниковых покровах территории Севера и Северо-Востока России и ее арктической подводной окраины, а также о связанных с оледенением процессах, включая гляциогидрологические, которые имели место в эпоху последнего великого похолодания (между 110 —115 и 8 —10 тыс. лет назад). Согласно авторской концепции, последняя (осташковско-сартанская) ледниковая система этой территории представляла собой сплошной Евразийский покров, включавший Скандинавский, Баренцево-Карский, Восточно-Сибирский, Берингийский и Охотский ледниковый щиты и объединявшие их шельфовые ледники. Весь этот сложный покров входил в качестве «русского компонента» в единую динамическую систему Панарктического ледникового покрова, центр которого лежал в районе Северного полюса. Даны трехмерные (объемные) реконструкции древнеледниковых покровов и показана их связь с другими компо- нентами природной среды ледникового периода, в том числе с уровнем океана. Рассматриваются также «жидкие ком- поненты» оледенения, его гидрологические системы, имеющие квазистационарный и «катастрофический» (потопный) режимы. Дается хронология потопов, предложена гипотеза, связывающая их генезис с неустойчивостью оледенения Арктического океана и его нелинейной реакцией на внешний форсинг. В сумме русские компоненты оледенения Арктики имели площадь до 10,65 млн км2 и объем 13,3 млн км3 льда, что было эквивалентно эвстатическому снижению уровня Мирового океана на 33,7 м. Эти реконструкции надежно вери- фицированы — подвергнуты тесту на согласованность. Тест показал, что они согласуются с осташковско-сартанским контекстом природной среды Евразии и Земли в целом, тогда как ни одна из альтернативных реконструкций того же оледенения с ним не согласуется. Иными словами, автор опровергает реконструкции, выполненные участниками Европейских и Русско-Американских проектов, предполагающие в Русской Арктике меньшие по размерам и «диа- хронные» ледниковые покровы. The last work of Mikhail Grosswald summarizes data about ice sheets of Russian North and North-East and its Arctic underwater periphery. It deals with the processes related to the glaciation such as glacio-hydrologycal ones taken place in the Last Great Chill (between 110 — 115 and 8 — 10 kBP). According to the author’s concept, the last glacier system on this terrain represented a continuous Eurasian Ice Sheet, which included Scadinavian, Barents-Kara, North-East Siberian, Beringian, and Okhotsk seas ice sheets and embraced their ice shelves. This compound ice sheet as a whole was a «Russian Component» in the integrated dynamic system of PanArctic Ice Sheet centered in the North Pole area. The work presents 3D reconstructions of the former ice sheets and shows their relationship with other environmental components of the Ice Age, including sea level. Hydrological systems of the former ice sheets, characteristic for quasi-sta- tionary and catastrophic regimes, are also under consideration. The work gives the chronology of floods. The hypotheses relating their genesis to the instability of the Arctic Ocean glaciation and its non-linear reaction on driving forcing is pre- sented. In sum, Russian components of the Arctic glaciation reached 10.65 millions km2 in area and 13.3 millions km3 in volume that was equivalent to the eustatic sea level drop at 33.7 m. These reconstructions are reliab ly verified, i.e. under- gone test on coherence. It showed that they are in conformity to the Ostashkovo-Sartan «context» of environment of Eurasia and globally, whereas no one alternative to the given for the same glaciation is not. In other words, the author denies reconstructions performed by the members of the European and Russia-USA projects, which suggest lesser size of the Russian Arctic glaciation and «diachronous» ice sheets. Оглавление Слово редактора . .2 Предисловие . 9 1. Введение . 11 1.1. История проблемы . .11 1.1.1. Начало . .11 1.1.2. Авторская концепция последнего оледенения . 13 1.1.3. Последний миллиард лет оледенений . .14 1.1.4. Минималистские модели . .14 1.2. Методы реконструкций, проверка результатов . 16 1.2.1. Геологический и геофизический методы . 16 1.2.2. Палеогляциологические методы . .17 1.2.3. Методы верификации результатов . .18 1.3. Терминология (глоссарий) . .19 2. Ледниковые покровы. Русский Север . 21 2.1. Вводные замечания . .21 2.1.1. Оледенение Западной Европы . .21 2.1.2. Проблемы оледенения Баренцево-Карского шельфа . .25 2.2. Баренцево-Карский ледниковый покров . .25 2.2.1. Краткая история концепции . 26 2.2.2. Аргумент траекторий разноса эрратики . .26 2.2.3. Аргумент «раковинной эрратики», или shelly drift . .28 2.2.4. Аргумент ориентировки ледниковых шрамов и дислокаций . .29 2.2.5. Аргумент строения дна Баренцева
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