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The uplift of the Tibetan Plateau was a significant event in terms of global landforms and climate, but the exact nature of the uplift process remains contested among geologists. In the uplifted inland area of the plateau, river-terrace formation has been controlled mainly by tectonic uplift, which means that analyses of river terraces are an excellent means of investigating the uplift process. In this paper, we establish the terrace sequence of the Yellow River in the Gonghe–Guide section of the northeastern Tibetan Plateau, making use of field investigations, gravel analysis, and electron spin resonance (ESR) dating. Terraces T3–T9 of the numbered sequence formed at ~ 0.13, 0.18, 0.23, 0.41, 0.85, 0.93, and 1.32 Ma, (moving backwards in time and upwards from the valley floor), whereas terraces T11–T20 formed at ~ 1.71, 1.75, 1.88, 1.94, 2.01, 2.12, 2.23, 2.31, 2.36, and 2.47 Ma. This suggests that the Yellow River existed in Gonghe and Guide basins for at least the last 2.47 Ma. The incision rates of the Yellow River in the Gonghe–Guide section indicate that there were three distinct phases of uplift of the northeastern Tibetan Plateau, occurring at different rates, with an average uplift rate of ~ 0.26 mm/yr during the Quaternary. These results support the multi-stage uplift model, which states that the Tibetan Plateau has experienced continuous uplift since 8 Ma, but contradicts both the early uplift theory, which holds that the uplift of the Tibetan Plateau occurred mainly before the Pliocene, and the notion of a late and rapid uplift of the plateau that began at 3.6 Ma.

The Miyun area of Beijing is located in the northern part of the North China Craton (NCC) and includes a variety of Archean granitoids and metamorphic rocks. Magmatic domains in zircon from a tonalite reveal Early Neoarchean (2752 +/- 7 Ma) ages show a small range in (Hf)(t) from 3.1 to 7.4 and t(DM1)(Hf) from 2742 to 2823 Ma, similar to their U-Pb ages, indicating derivation from a depleted mantle source only a short time prior to crystallization. SHRIMP zircon ages of granite, gneiss, amphibolite and hornblendite in the Miyun area reveal restricted emplacement ages from 2594 to 2496 Ma. They also record metamorphic events at ca. 2.50 Ga, 2.44 Ga and 1.82 Ga, showing a similar evolutionary history to the widely distributed Late Neoarchean rocks in the NCC. Positive (Hf)(t) values of 1.5 to 5.9, with model ages younger than 3.0 Ga for magmatic zircon domains from these Late Neoarchean intrusive rocks indicate that they are predominantly derived from juvenile crustal sources and suggest that significant crustal growth occurred in the northern NCC during the Neoarchean. Late Paleoproterozoic metamorphism developed widely in the NCC, not only in the Trans-North China Orogen, but also in areas of Eastern and Western Blocks, which suggest that the late Paleoproterozoic was the assembly of different micro-continents, which resulted in the final consolidation to form the NCC, and related to the development of the Paleo-Mesoproterozoic Columbia or Nuna supercontinent.

Terrace formation processes can reflect the evolution of large rivers. The Hetao Basin is a floodplain of the Yellow River, and there are two to three terraces that extend E–W on the northern margin. Based on a detailed field geological survey and measurement of the terrace sections, combined with sedimentological and chronological analyses, we reconstructed the developmental processes of the three terraces and inferred that three river terraces were formed by the Yellow River. The OSL dating results show that the time of deposition of terrace 3 was prior to 118 ka BP. Subsequently, the terrace began to experience incision and formed the geomorphic surface of terrace T3. Similarly, terrace 2 and terrace 1 were mainly deposited from ~ 109 and 59 ka, respectively; and began to be incised prior to 71 and 46 ka, respectively. The three terraces in the northern Hetao Basin are the products of the combined actions of climatic shifts and tectonic uplift. The Yellow River's evolutionary history in the Hetao area since the Late Pleistocene is discussed. Before about 120 ka BP, the Yellow River may have flowed through the northern Hetao Basin. Between 110 and 70 ka BP, the Yellow River experienced at least two changes between river and lake sedimentation. From 60 to 50 ka, a very large river-connected lake of the Yellow River was developed in the Hetao Basin. After 50 ka, the Hetao river-connected paleolake of the Yellow River gradually dried.

Field investigation has shown that the middle reaches of the Yarlung Zangbo River, in Tibet (known as the Bhramaputra River in reaches downstream) has 11 terraces. The ages of these terraces were determined as follows: T11>2000 ka, T10 = 1783 ka, T9 = 1238 ka, T8 = 683 ka, T7 = 382 ka, T6 = 150 ka, T5 = 82 ka, T4 = 67 ka, T3 = 43 ka, T2 = 28 ka and T1 = 10 ka. These terraces formed during several stages of the Quaternary when the Tibetan Plateau was uplifting, recording tectonic–climatic cycles or subcycles of 1.2, 0.4, 0.1, 0.04 and 0.02 million years duration. The tectonic–climatic cycles identified by this study are correlated with red soil and palaeosol records. The preservation of the Oligocene to Early Miocene conglomeratic Dazhuka Formation, close to the present altitude of the main planation surface of the Tibetan Plateau and occurring only in the Yarlung Zangbo valley, suggests that this river has existed since at least 7 Ma. Discoveries of old and thick fluvial gravel layers extending to within 630 m of the valley floor show that the Yarlung Zangbo River was already incised by 2000 m or more below the surface of the Tibetan Plateau, that much of the incision from plateau to valley floor had been accomplished and that the plateau was already substantially uplifted prior to the Quaternary. In addition to its importance for understanding the evolution of the Tibetan Plateau, this study documents the impact of varying rates of tectonic uplift on river development.

The Miyun Geopark is located in the northern part of the North China Craton and includes a variety of Archean granitoids and metamorphic rocks. SHRIMP zircon dating documents their emplacement ages at 2567–2508 Ma, metamorphic events at ca. 2.50 Ga, 2.44 Ga, and 1.82 Ga. Late Neoarchean basement rocks elsewhere in the North China Craton document a similar evolutionary history with intrusion of granitoid rocks commencing at ca. 2590 Ma and reaching three peaks at about 2550, 2520, and 2500 Ma; these rocks then underwent regional metamorphisms at ca. 2.50 Ga, 2.44 Ga, 1.92 Ga, and 1.82 Ga. Positive e Hf( t ) values of + 1.7 to + 7.6, with model ages younger than 3.0 Ga, for magmatic zircons from these late Neoarchean intrusive rocks indicate that they are predominantly derived from juvenile crustal sources and suggest that significant crustal growth occurred in the northern North China Craton during the Neoarchean. The intrusive rocks in the Miyun area are part of an extensive province of late Neoarchean magmatism and appear to be related to mantle plume activity at this time.

On both sides of the Jinsha River valley near Benzilan, Deqen, northwest of Yunnan, China, a series of varied lacustrine deposits have been discovered under the fourth terrace (Q(3)(2)). Landslide debris has been identified underlying the lacustrine deposits, indicating that the lacustrine deposits were caused by a landslide damming the Jinsha River. U-series dating shows that the age of the upper and middle portions of the lacustrine deposits on the right bank were 55.4 +/- 3.5 and 82.1 +/- 6.6 ka respectively. Lacustrine deposits on the left bank have been dated to 122.0 +/- 12.4 ka at the bottom, which indicates that the large-scale landslide was formed before 122.0 +/- 12.4 ka and the paleo-lake was developed within the early stage to the mid-stage of the Late Pleistocene. The characteristic of spore-pollen and high content of CaCO(3) in the lacustrine clays reveal that the paleoclimate was semi-arid with less heavy rainfall. Considering the regional neotectonic background, the authors prefer to interpret that the Benzilan ancient landslide-dammed lake was caused by an ancient earthquake. The discovery of the ancient landslide-dammed lake provides significance to the understanding of the formation and evolvement of calamitous geological hazards along large rivers. (C) 2010 Elsevier Ltd and INQUA. All rights reserved.

The regional geologic and geomorphic observations show that an active arcuate normal fault constitutes the main boundary fault of the Haba-Yulong Snow Mountains (HYSM). This fault is called eastern piedmont fault of Haba-Yulong Snow Mountains (HYPF). The fault consists of two segments with differential trend; the northern segment is NW-trending and NE-dipping and the southern section is S-N trending and E-dipping. Three sets of fault scarps cutting late Quaternary landforms and their dating results indicate that the fault is a prominent Holocene active fault and its throw rates are 0.3–1.4 mm/a during late Quaternary. The geometry and kinematics of the fault suggest that the arcuate normal faulting or rifting are typical surface deformation pattern at the two tips of the Z-shaped rift zone of northwestern Yunnan, which is related to regional east-west extension accompanying clockwise rotation of micro-block.

The Yunmengshan Geopark in northern Beijing is located within the Yanshan range. It contains the Yunmengshan batholith, which is dominated by two plutons: the Yunmengshan gneissic granite and the Shicheng gneissic diorite. Four samples of the Yunmengshan gneissic granite give SHRIMP zircon U–Pb ages from 145 to 141 Ma, whereas four samples of the Shicheng gneissic diorite have ages from 159 Ma to 151 Ma. Dikes that cut the Yunmengshan diorite record SHRIMP zircon U–Pb age of 162±2 and 156±4 Ma. The cumulative plots of zircons from the diorites show a peak age of 155 Ma, without inherited zircon cores, and the peak age of 142 Ma for granite is interpreted as the emplacement age of the Yunmengshan granitic pluton, whose igneous zircons contain inherited zircon cores. The data presented here show that there were two pulses of magmatism: early diorites, followed c13 Ma later by true granites, which incorporated material from an older continental crust.

A paleosol dated for about 500–700 kaBP and developed on a glacial deposit at ∼3 000 m a.s.l. in the Yulong Mountains is studied using soil chemical, morphological and mineralogical methods. The analytical results indicate that this soil was formed under tropical and humid conditions and can be classified as red soil, which cannot be formed in the present alpine environment at the studied site. This implies that the southeast margin of the Tibetan Plateau has experienced intense uplift since the formation of the paleosol. According to the necessary conditions for the formation of the modern red soil in China, we estimate that the uplift height of the Plateau since 500–700 kaBP would have exceeded 800 m.

The authors have made a further investigation on the tidal-zone paleoforest remains found in the Shenhu bay, Fujian Province. By surveying (scale of 1:500) and numbering of the remains, 65 tree trunks were found. They are relatively concentrated in three different regions from south to north. Their growing ages ranged from 45 a to 100 a. 22 ancient trunks’ sections with low degree of carbonization show that the paleoforest was composed of Keteleeria Carr., Morus L. and Gleditsia L. 14C dating shows that the paleoforest was living in 9 420–6760 aBP. Later it stopped developing and was buried by the alluvial aggradation caused by the sea level rise.