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泰国、老挝和越南白垩纪沉积全属非海相,它们广泛分布于泰国北部、东北部、西南部和南部,老挝北部、中部和南部,越南东北部、西北部、中部和南部。泰国南部的白垩纪地层分为Lam Thap,Sam Chom和Phun Phin组;其他地区,特别是西北部的呵叻高原地区的白垩系属呵叻群的Phra Wihan,Sao Khua,Phu Phan,Khok Kruat,Maha Sarakham及Phu Thok组。在老挝,万象盆地的白垩系由老挝呵叻群的NamSet,Phu Phanang,Ban Ang,Champa和Ban Thalat组与丰洪群的Thangon和Saysomboun组组成;沙湾拿吉(东兴)盆地的白垩系由南通(河)群的Nam Phouan,Nam Xot,Nam Noy和Nong Boua组组成。越南的白垩系在西北部分为Nam Na,Yen Chau,Van Chan和Ngoi Thia组,东北部为Ban Hang组,中部分为NhaTrang,Mu Gia和Dong Dzuong组,南部则为Phu Quoc组。三国白垩系的岩性普遍以红棕色至浅灰色砂岩、砾(岩质)砂岩、粉砂岩、泥岩和砾岩为主。泥岩中具有钙质结核和硅结砾岩,但盐和石膏仅见于Maha Sarakham,Saysomboun和Yen Chau组内。过去,这些白垩纪地层的生物地层没有经过详细研究。根据地层层序和化石对比,在泰国东北部呵叻高原和南部半岛地区及老挝南部沙湾拿吉(东兴)盆地中识别出了2个标记非海相白垩纪的类三角蚌类化石组合:阿普特期(但可上延至阿尔必期)的Trigonioides(Trigonioides)kobayashi-Plicatounio(Guangxiconcha)suzukii组合,阿普特阿尔必期(但主要为阿尔必期)的Trigonioides(Diversitrigonioides)diversicostatus-Pseudohyria subovalis组合。越南中部可能也产早白垩世阿普特阿尔必期的类三角蚌类双壳类Plisatouniosp.-Trigonioidessp.组合。通过双壳类组合,并结合包括孢粉和恐龙在内的其他化石的对比,泰国北部和南部、老挝南部和越南中部的非海相白垩纪地层得到了定年和对比,从而揭示了东南亚非海相白垩纪盆地的演化历史。
The Cretaceous deposits in Thailand, Laos and Vietnam are all non-marine. They are widely distributed in northern Thailand, northeast, southwestern and southern Thailand, northern Laos, central and southern Vietnam, northeastern Vietnam, northwestern, central and southern Thailand. The Cretaceous strata in southern Thailand are divided into the Lam Thap, Sam Chom and Phun Phin formations; other areas, notably the Phra Wihan, Sao Khua, Phu Phan, Khok Kruat, Cretaceous Korats in the Nakhon Ratchasima Plateau in the northwest, Maha Sarakham and Phu Thok. In Laos, the Cretaceous in the Vientiane Basin consists of the Thangon and Saysomboun formations of the Fenghong Group in the NamSet, Phu Phanang, Ban Ang, Champa and Ban Thalat formations of the Nyuratu group in Laos; the Cretaceous of the Savannakhet Nam Phouan, Nam Xot, Nam Noy and Nong Boua formations in Nantong (river) group. The Cretaceous in Vietnam are Nam-Na, Yen-Chau, Van-Chan and Ngoi-Thia in the northwest, Ban Hang in the northeast, NhaTrang, Mu Gia and Dong Dzuong in the middle and Phu Quoc in the south. The Cretaceous lithology of the Three Kingdoms are generally reddish brown to light gray sandstone, gravel (rock) sandstone, siltstone, mudstone and conglomerate. The mudstone has calcareous nodules and silicon-bearing conglomerates, but salt and gypsum are found only in the Maha Sarakham, Saysomboun and Yen Chau formations. In the past, these strata of the Cretaceous stratigraphy have not been studied in detail. Based on the stratigraphic sequence and fossil correlation, two Cretaceous-like Hypha-Triangulum muscovite assemblages were identified in the Nakhon Ratchapa Plateau and the Southern Peninsula in northeastern Thailand and the Savannakhet (Dongxing) basin in southern Laos: Trigonioides (Trigonioides) kobayashi-Plicatounio (Guangxiconcha) suzukii in the Aptian phase (but up to Albinism), Trigonioides (Diversitrigonioides) diversicostatus-Pseudohyria subovalis combination. Central Asia may also produce Early Cretaceous Apt Albian clam-like Plisatouniosp.-Trigonioidessp. Combination. Comparing bivalve assemblages with other fossils including sporopollen and dinosaurs, non-marine Cretaceous strata in northern and southern Thailand, southern Laos and central Vietnam have been dated and compared, revealing the non-marine Cretaceous basin evolutionary history.