The Phanerozoic record of Southeast Asia preserves the history of opening and subsequent consumption of the Paleotethyan Ocean and the assembly of continental fragments into Asia as part of the ...broader-scale reconstruction of Pangea. However, uncertainty remains as to which of the many suture zones in Southeast Asia represents the relict of the main ocean, when final ocean closure occurred, and the assembly history of the Eastern Cimmerian and Southeast Asia continental fragments. Our overview of the geological features of the suture zones, the bounding continental fragments and their magmatic, metamorphic and sedimentary records resolves many of these key issues. The sedimentary, biogeographical, structural, lithological, geochemical and geochronological data from the Changning-Menglian, Inthanon and Bentong-Raub suture zones argue for their linkage with the Longmu Co-Shuanghu suture zone in Central Tibet, and together constitute the main East Paleotethyan Ocean relict. The eastward subduction of the ocean resulted in the development of a series of magmatic arc-back-arc basin and continental fragments in Southeast Asia, including, from west to east, the Lincang-Sukhothai-East Malaya arc, the Jinghong-Nan-Sa Kaeo back-arc basin, the Simao/west Indochina fragment, the Luang Prabang-Loei back-arc basin, the south Indochina fragment, the Wusu and Truong Son back-arc basins, the north Indochina fragment, the Jinshajiang-Ailaoshan-Song Ma branch/back-arc basin and the South China Block. Assembly of these fragments resulted in Indosinian high temperature and high pressure metamorphism and related tectonothermal event. Available data indicate a switch from subduction of the main East Paleotethyan Ocean to the collision of the Sibumasu with Simao/Indochina blocks at ~237Ma, with subsequent syn- and post-collisional events at ~237–230Ma and ~230–200Ma, respectively, along the Changning-Menglian, Inthanon and Bentong-Raub suture zones. The timing of initial-, syn- and post-collision events along the Jinshajiang-Ailaoshan-Song Ma suture zone with its record of back-arc basin closure is at ~247Ma, ~247–237Ma and ~237–200Ma, generally ~10Ma older than that along the Changning-Menglian, Inthanon and Bentong-Raub suture zones. Our synthesis of all available data enables establishment of a comprehensive geodynamic model for the East Paleotethyan evolution. This model links the spatial-temporal pattern across Southeast Asia into a series of tectonic events including ocean/back-arc basin opening, subduction/closure, subsequent assemblage and orogenic collapse, along with associated igneous, metamorphic and sedimentary activities.
To improve silage quality of crop forages, bacterial inoculants are often employed. In this study, Lactobacillus brevis SDMCC050297 and Lactobacillus parafarraginis SDMCC050300 were used as ...inoculants to corn stover in lab silos for ensiling. At the initial stage of ensiling, the pH value of the inoculated silages reduced more drastically, and the inoculated silages had higher lactic acid and acetic acid contents. After 20 days of ensiling, a reduction in lactic acid content coupled with an increase in acetic acid and 1,2-propanediol contents was observed in inoculated silages. Furthermore, both the amount of lactic acid bacteria and the abundance of order Lactobacillales in inoculated silages were higher than those of controls in the whole process. Meanwhile, Lb. brevis predominated before day 20 and then the dominance was shifted to Lb. parafarraginis until the late stage of ensiling. In contrast, the epiphytic Lactococcus lactic and Lb. plantarum played major roles at the beginning of naturally fermented silages and then Lb. plantarum and Lb. brevis were the most abundant at the later stage. In conclusion, these two selected strains had capability of improving the silage quality and providing the reproducible ensiling process, thus having the potential as silage inoculants.
Dear Editor, Lysine crotonylation is a posttranslational modifi- cation （PTM） of histone proteins originally identified by Tan et al. 1. This novel evolutionarily conserved histone modification was ...identified on 28 lysine sites on various histones 1. Lysine crotonylation occurs primar- ily on the ε-amino group of lysine, but its planar orien- tation and four-carbon length distinguish it from lysine acetylation. Histone crotonylation specifically labels the enhancers and transcription starting sites of active genes in both the human somatic cell genome and the murine male germ cell genome. Histone crotonylation, like acetylation.
Contrasting models for internal and external locations of South China within the Nuna and Rodinia supercontinents can be resolved when the current lithotectonic associations of Mesoproterozoic and ...older rocks units that constitute the craton are redefined into four lithotectonic domains: Kongling, Kunming-Hainan, Wuyi, and Coastal. The Kongling and Kunming-Hainan domains are characterized by isolated Archean to early Paleoproterozoic rock units and events and crop out in northern and southern South China, respectively. The Kunming-Hainan Domain is preserved in three spatially separated regions at Kunming (southwestern South China), along the Ailaoshan shear zone, and within Hainan Island. Both domains were affected by late Paleoproterozoic tectonothermal events, indicating their likely juxtaposition by this time to form the proto-Yangtze Block. Late Paleoproterozoic and Mesoproterozoic sedimentary and igneous rock units developed on the proto-Yangtze Block, especially in its southern portions, and help link the rock units that formed along the shear zone at Ailaoshan and on Hainan Island into a single, spatially unified unit prior to Paleozoic to Cenozoic structural disaggregation and translation. The Wuyi Domain consists of late Paleoproterozoic rock units within a NE-SW trending, fault-bounded block in eastern South China. The Coastal Domain lies east of the Wuyi domain and is inferred to constitute a structurally separate block. Basement to the domain is not exposed, but zircon Hf model ages from Mesozoic granites suggest Mesoproterozoic basement at depth.
The Archean to Paleoproterozoic tectonothermal record of the Kongling and Kunming-Hainan domains corresponds closely with that of NW Laurentia, suggesting all were linked, probably in association with assembly and subsequent partial fragmentation of the Nuna supercontinent. Furthermore, the age and character of Mesoproterozoic magmatism and detrital zircon signature of sedimentary rocks in the proto-Yangtze Block matches well with western Laurentia and eastern Australia-Antarctica. In particular, the detrital zircon signature of late Paleoproterozoic to early Mesoproterozoic sedimentary units in the block (e.g. Dongchuan Group) share a similar age spectrum with the Wernecke Supergroup of northwest Laurentia. This, together with similarities in the type and age of Fe-Cu mineralization in the domain with that in eastern Australia-Antarctica, especially northeast Australia, suggests a location adjacent to northwest Laurentia, southern Siberia, and northeast Australia within the Nuna supercontinent.
The timing and character of late Paleoproterozoic magmatic activity in the Wuyi domain along with age of detrital zircons in associated sedimentary rocks matches the record of northern India. During rifting between Australia–Antarctica and Laurentia in the late Mesoproterozoic, the proto-Yangtze Block remained linked to northeast Australia. During accretionary orogenesis in the early Neoproterozoic, the proto-Yangtze Block assembled with the Wuyi Domain along the northern margin of India. The Coastal domain likely accreted at this time forming the South China Craton. Displacement of the Hainan and Ailaoshan assemblages from southwest of the Kunming assemblage likely occurred in the Cenozoic with the activation of the Ailaoshan-Red River fault system but could have begun in the early to mid-Paleozoic based on evidence for tectonothermal events in the Hainan assemblage.
New U-Pb geochronological, petrologic, elemental and Sr-Nd-Hf-O isotopic data for the granites from the Inthanon and Sukhothai zones in NW Thailand in conjunction with correlations with SW China are ...presented to constrain the age and position of the Paleotethys Ocean in this region and the associated assembly of Southeast Asia. The geochronological data show that the granitic rocks in the Inthanon and Sukhothai zones, herein named Group 1 and Group 2 granites, respectively, yield similar crystallization ages of 230–200Ma. Group 1 samples are characterized by monzogranite and granite with I- and S-type geochemical affinity and Group 2 samples by I-type monzogranite and granodiorite. They have generally similar chondrite-normalized REE and PM-normalized multi-element patterns but distinct Sr-Nd-Hf-O isotopic compositions. Group 1 samples have slightly higher initial 87Sr/86Sr ratios (0.7111–0.7293) but lower εNd(t) values (−11.1 to −14.1) than those of Group 2 samples (87Sr/86Sr(i)=0.7073–0.7278 and εNd(t)=−8.3 to −11.0). Group 1 samples show the lower εHf(t) values (−5.4 to −18.2), older TDM (1.62–2.40Ga) and higher δ18O values (+7.95 to +9.94) than those of Group 2 samples (εHf(t) of −11.1 to +4.80, TDM of 0.96–1.95Ga and δ18O of +4.95 to +7.98) for the Triassic crystallization zircons. These geochemical signatures are similar to the Kwangsian and Indosinian granites in the South China and Indochina blocks but distinct from those of the Gangdese I-type granite and Sibumasu Paleozoic granite. Our data suggest that Group 1 samples mainly originated from the early Paleozoic supracrustal rocks containing metapelite and metavolcanic components, which had previously experienced the surface weathering. Group 2 samples were derived from a hybridized source of an old metamorphic and a newly underplated mafic component. Synthesis of our data with available regional observations indicates that the Inthanon zone represents the main suture zone of the eastern Paleotethyan Ocean in NW Thailand and links with the Changning-Menglian suture zone in SW Yunnan (SW China). In NW Thailand, a switch from the eastward subduction of the Paleotethyan oceanic plate to the collision of the Sibumasu with Indochina blocks occurred at ~237Ma, and syn- and post-collisional time being at ~237–230Ma and ~200–230Ma, respectively. The late Triassic granites in the Inthanon and Sukhothai zones are representative of the post-collisional magmatic products.
•The granitic rocks in the Inthanon and Sukhothai zones yield the zircon U-Pb crystallization ages of 230–200Ma.•The Inthanon and Sukhothai granites show similar elemental but distinct Sr-Nd-Hf-O isotopic compositions, respectively.•The Inthanon and Sukhothai granites mainly originated from the supracrustal and underplating rocks, respectively.•The Inthanon zone represents the main suture zone of the eastern Paleotethyan Ocean in NW Thailand.•The syn- and post-collisional events in NW Thailand occurred at ~237–230Ma and ~200–230Ma, respectively.
Display omitted
•There are ∼330 Ma, ∼257 Ma and ∼240 Ma mafic-intermediate rocks along the Bangxi-Chenxing zone.•These rocks have MORB- and arc-like geochemical affinities.•They formed in a back-arc ...basin, continental-arc and post-collisional setting, respectively.•The Bangxi-Chenxing zone is the eastern extension of the Song Ma–Ailaoshan tectonic zone.
Mafic-intermediate igneous rocks in the Bangxi-Chenxing tectonic zone of Hainan Island, South China, can be used to constrain the Paleotethyan tectonic evolution in Southeast Asia. This paper presents petrologic, geochronological, elemental and Sr–Nd–Hf–O isotopic data for Carboniferous basalts, Permian andesites and Triassic gabbro-dolerites in this zone. Zircon grains from these rocks have U-Pb ages of ∼330 Ma, ∼257 Ma and ∼240 Ma, respectively. The ∼330 Ma basalts contain 1400 Ma captured zircon grains, and display MORB-like geochemical characteristics with positive εNd (t) values of +5.86–+9.85, reflective of a MORB source with the input of a slab-derived component in a continental back-arc basin setting. The ∼257 Ma andesites contain older captured zircon grains, and have arc-like geochemical signature with weakly positive εNd (t) values of +0.26–+0.38, zircon εHf (t) values of −0.5–+1.4 and δ18O values of 6.35–7.16‰, which were derived from a metasomatized mantle wedge modified by the sediment-derived component in a continental arc setting. The ∼240 Ma gabbro-dolerites exhibit enrichment in LILEs, depletion in HFSEs, negative εNd (t)-εHf (t) values (−8.45 to −1.05 and −5.9 to −2.7, respectively) and crustal-like δ18O values (7.26–8.70‰), indicative of a post-collisional environment in response to the asthenosphere upwelling shortly after the closure of the Bangxi-Chenxing back-arc basin. The Carboniferous-Triassic mafic-intermediate igneous rocks thus record the Carboniferous-Permian arc-basin system and its Triassic closure. The Bangxi–Chenxing tectonic zone separated South Hainan from North Hainan and westerly extended to the Song Ma–Ailaoshan suture zone.
Clear cell renal cell carcinoma （ccRCC） is one frequent form of urologic malignancy with numerous genetic and epigenetic alterations. This review summarizes the recent major findings of epigenetic ...alterations including DNA methylation, histone modifications, microRNAs and recently identified long noncoding RNAs in the development and progression of ccRCC. These epigenetic profilings can provide a promising means of prognostication and early diagnosis for patients with ccRCCs. With the developed high- throughput technologies nowadays, the epigenetic analyses will have possible clinical applications in the molecular pathology of ccRCC.
The basaltic rocks in NW Thailand belong to part of giant Southeast Asian igneous zone that delineates the extension of the Paleotethyan Ocean from SW China into NW Thailand. The Chiang Mai basaltic ...samples from the Chiang Dao, Fang, Lamphun and Ban Sahakorn sections are divisible into two groups of high-iron basalt. Group 1 has SiO2 of 38.30–49.18wt.%, FeOt of 13.09–25.37wt.%, MgO of 8.38–1.60wt.%, TiO2 of 3.92–6.30wt.%, which is rarely observed in nature. Group 2 shows SiO2=44.71–49.21wt.%, FeOt=10.88–14.34wt.%, MgO=5.24–16.11wt.%, TiO2=2.22–3.07wt.% and mg#=44–70. Olivine and pyroxene are responsible for the fractionation of the Group 2 magma whereas low oxygen fugacity during the late-stage differentiation of the Group 1 magma prolonged fractionation of ilmenite and magnetite. The onset of ilmenite and magnetite fractionations controls the distinct differentiation commencing at MgO=~7wt.%. Both groups show similar REE and primitive mantle-normalized patterns with insignificant Eu, Nb-Ta and Zr-Hf anomalies. They have similar Nd isotopic compositions with εNd (t) values ranging from +2.8 to +3.7 and similar Nb/La, Nb/U, Th/La, Zr/Nb, Th/Ta, La/Yb, Nb/Th, Nb/Y and Zr/Y, resembling those of OIB-like rocks. The representative basaltic sample yields the argon plateau age of 282.3±1.4Ma, suggestive of Early Permian origin. Our data argue for Group 1 and Group 2 are coeval in the intra-oceanic seamount setting within the Paleotethyan Ocean, which at least continued till 283Ma. These data, along with other observations, suggest that the Inthanon zone defines the main Paleotethyan suture zone, which northerly links with the Changning-Menglian suture zone in SW China.
•The Chiang Mai basaltic rocks are characterized by high-Fe basalts with distinct differentiation trends.•These basalts in NW Thailand originated from an OIB-like source in the Paleotethyan intra-oceanic seamount setting.•The Inthanon zone defines the Paleotethyan main suture with the Chiang Rai Fault for the easternmost boundary.
Felsic igneous rocks in northern Laos are key elements of the Truong Son and Song Ma tectonic zones and are important for constraining the Paleotethyan evolution in southeastern Asia. This paper ...presents new geochronological, geochemical and Sr–Nd–Hf–O isotopic data from granitoids and rhyolites in northern Laos. Geochronological data show that these samples have zircon U-Pb ages ranging from ca. 281 Ma to 221 Ma. These samples can be subdivided into four groups based on their lithology and geochemical composition. Group 1 samples are granodiorite and granite with I-type geochemical characteristics. They have lower 87Sr/86Sr (i) ratios (0.7036–0.7059) and higher εNd (t) values (+0.7 − +0.8) than Group 2 biotite granite samples (87Sr/86Sr (i) = 0.7087–0.7129 and εNd (t) = −5.3 to −9.2) and Group 3 rhyolite samples (87Sr/86Sr (i) = 0.7092–0.7103 and εNd (t) = −5.9 to −8.9). Zircon grains from Group 1 samples yield positive εHf (t) values of +5.1 − +13.8, TDM ages of 0.37–0.71 Ga and δ18O values of 5.6–6.3‰. In contrast, zircons from Group 2 and Group 3 samples have mainly negative εHf (t) values (−9.6 to +1.6 and −4.7 to −14.7), older TDM ages (1.08–1.70 Ga and 1.42–1.97 Ga), and higher δ18O values (5.7–10.3‰ and 6.7–8.0‰), respectively. Our geochemical data suggest that the Group 1 granite samples are the products of the partial melting of newly underplated mafic rocks, whereas the Group 2 and 3 samples originated from a mixed source of “ancient” metaigneous and metagreywacke components. Group 4 samples include Late Triassic I-type granodiorite and granite and have εNd (t) = −1.9 to −3.9, 87Sr/86Sr (i) = 0.7079–0.7084, zircon εHf (t) = 0.0 − +7.5, and δ18O = 5.1–6.9‰, indicating a derivation from a metagreywacke source with a component of juvenile mafic crust. Our data suggest that the Permian felsic igneous rocks in northern Laos formed in an arc setting related to the Song Ma Paleotethyan branch/BAB subduction, whereas the Late Triassic I-type granitoids formed in a post-collisional setting in response to the gravitational collapse of thickened crust during the collision of the South China and Indochina blocks. The temporal-spatial pattern of igneous rocks along the Truong Son zone is related to the Paleotethyan evolution and resembles that along the Ailaoshan-Song Ma zone and its eastward extension in northern Hainan.
Display omitted
•Granitoids and rhyolites exposed in northern Laos yield zircon ages of 281–221 Ma•These rocks can be subdivided into four groups based on lithology and geochemical compositions•Group 1–3 granitoids and rhyolites in northern Laos formed in an arc setting•Group 4 granitoids in northern Laos formed in a post-collisional setting
•The Baoban mafic rocks in southwest Hainan formed at 1441–1424 Ma.•The Mesoproterozoic Baoban Complex formed in the syn-rifting setting of the Columbia breakup.•southwest Hainan connected with west ...Laurentia and Australia in Columbia reconstruction.
New U-Pb geochronological, elemental and Nd-Hf isotopic data for the metamorphic mafic rocks from the Baoban Complex in southwest Hainan provide new constraints on their petrogenesis and geodynamic setting. Magmatic zircons from the representative samples yielded weighted mean 207Pb/206Pb ages of 1441–1424 Ma, representing their crystallization ages. These samples show subalkaline to alkaline characteristics and can be geochemically subdivided into three groups in spite of similar formation time. Group 1 has TiO2 of 2.85–3.18 wt.%, Nb of 20.5–21.6 ppm, Nb/U of 45–49, Nb/La of 1.22–1.37, εNd (t) of +6.8–+6.9 and zircon εHf (t) of +9.3–+12.7, suggestive of the derivation from OIB-like source. Group 2 shows Nb contents ranging from 1.0 ppm to 12.6 ppm, εNd (t) values from +5.5 to +5.9 and zircon εHf (t) values from +10.3–+12.4 with right-sloping REE-normalized pattern, indicative of an E-MORB source. Group 3 is characterized by negative Nb-Ta anomalies with Nb/La ratios of 0.51–0.88 and εNd (t) value of ∼+5.1, indicative of the derivation from a previously-metasomatized mantle source. The coeval mafic and felsic rocks in the Baoban Complex are geochronologically and geochemically comparable to the Mesoproterozoic intra-plate magma in southwest Laurentia. The Mesoproterozoic Baoban igneous rocks are generated in a syn-rift setting in response to the Columbia breakup. Southwest Hainan might connected with west Laurentia and Australia at ∼1.43 Ga.
PDF
