Bivalve shell fossils,cemented by authigenic carbonates,are widely spread in the Haima cold seep,Qiongdongnan Basin of the South China Sea(SCS).In this study,we examined an element profile of Gigantidas platifrons in ...Bivalve shell fossils,cemented by authigenic carbonates,are widely spread in the Haima cold seep,Qiongdongnan Basin of the South China Sea(SCS).In this study,we examined an element profile of Gigantidas platifrons in the Haima cold seeps at a water depth of 1381 m.Based on the scanning electron microscope(SEM)analyses,the prismatic layer and nacreous layer were identified,which are characterized by prismatic structure and stratified structure,respectively.In addition,the profile can be subdivided into two parts:altered and unaltered zones.Laser inductively coupled plasma mass spectrometry(LA-ICP-MS)mapping shows that the element concentrations of the altered zones were influenced by the authigenic carbonate rocks,whereas the element concentrations of unaltered zones remain stable.In-situ X-ray diffraction(XRD)analyses show that the mineral constituent of the prismatic layer is mainly composed of aragonite.Along with the growth profile,Mg/Ca ratios of unaltered zones have minor variations,ranging 0.72-0.97 mmol/mol(mean=0.87 mmol/mol),with estimated temperatures of 3.8-4.1℃,indicating that the temperature of the surrounding seawater remains constant and agree with the measured data of 3.9℃which was conducted by a conductivity-temperature-depth system(CTD).The minor variations of Ba/Ca ratios(0.01-0.06 mmol/mol;mean=0.04 mmol/mol)indicate a relatively stabilized salinity of the surrounding seawater.S/Ca ratios show large variations of 0.04-4.15 mmol/mol(mean=1.37 mmol/mol).S/Ca ratios have regular variations which generally correspond to the variations of the Mg/Ca ratios,highlighting that the S/Ca ratios of bivalve shells show the potential to reflect the growth rate of the Gigantides.However,further studies should be carried out on the understanding of the links between the S/Ca ratios and seepage intensity of cold-seep fluids.展开更多
Dear Editor,Polycomb group(Pc G)proteins represent important roles in repressing gene expression throughout development.The Polycomb repressive complexes(PRCs)have been subdivided into two central protein complexes,PR...Dear Editor,Polycomb group(Pc G)proteins represent important roles in repressing gene expression throughout development.The Polycomb repressive complexes(PRCs)have been subdivided into two central protein complexes,PRC1 and PRC2.PRC1 catalyzes H2AK119ub and PRC2catalyzes H3K27me1/2/3(Fursova et al.,2019).PRC1 is further categorized as CBX-containing canonical PRC1(c PRC1)and RYBP/YAF2-containing variant PRC1(v PRC1)(Blackledge and Klose,2021).展开更多
The early history of Earth is poorly understood,due to the lack of ancient rocks formed after the formation of the newborn Earth,especiallyfor thefirst 500 million years(Hadean Eon).To our knowledge,this period is the...The early history of Earth is poorly understood,due to the lack of ancient rocks formed after the formation of the newborn Earth,especiallyfor thefirst 500 million years(Hadean Eon).To our knowledge,this period is the most geodynamically vigorous in the crustal evolution history of Earth[1],and is characterized by intense collision with meteorites and the formation of a global magma ocean(~4.41 Ga;cf.review article by Ref.[2]).展开更多
基金Supported by the Key Research and Development Project of Guangdong Province(No.2020B1111510001)the National Natural Science Foundation of China(No.U2244224)+1 种基金the PI Project of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(No.GML2020GD0802)the Guangdong Special Support Team Program(No.2019BT02H594)。
文摘Bivalve shell fossils,cemented by authigenic carbonates,are widely spread in the Haima cold seep,Qiongdongnan Basin of the South China Sea(SCS).In this study,we examined an element profile of Gigantidas platifrons in the Haima cold seeps at a water depth of 1381 m.Based on the scanning electron microscope(SEM)analyses,the prismatic layer and nacreous layer were identified,which are characterized by prismatic structure and stratified structure,respectively.In addition,the profile can be subdivided into two parts:altered and unaltered zones.Laser inductively coupled plasma mass spectrometry(LA-ICP-MS)mapping shows that the element concentrations of the altered zones were influenced by the authigenic carbonate rocks,whereas the element concentrations of unaltered zones remain stable.In-situ X-ray diffraction(XRD)analyses show that the mineral constituent of the prismatic layer is mainly composed of aragonite.Along with the growth profile,Mg/Ca ratios of unaltered zones have minor variations,ranging 0.72-0.97 mmol/mol(mean=0.87 mmol/mol),with estimated temperatures of 3.8-4.1℃,indicating that the temperature of the surrounding seawater remains constant and agree with the measured data of 3.9℃which was conducted by a conductivity-temperature-depth system(CTD).The minor variations of Ba/Ca ratios(0.01-0.06 mmol/mol;mean=0.04 mmol/mol)indicate a relatively stabilized salinity of the surrounding seawater.S/Ca ratios show large variations of 0.04-4.15 mmol/mol(mean=1.37 mmol/mol).S/Ca ratios have regular variations which generally correspond to the variations of the Mg/Ca ratios,highlighting that the S/Ca ratios of bivalve shells show the potential to reflect the growth rate of the Gigantides.However,further studies should be carried out on the understanding of the links between the S/Ca ratios and seepage intensity of cold-seep fluids.
基金supported by the National Natural Science Foundation of China(31925009,U21A20195)the National Key Research and Development Program of China(2021YFA1100300)。
文摘Dear Editor,Polycomb group(Pc G)proteins represent important roles in repressing gene expression throughout development.The Polycomb repressive complexes(PRCs)have been subdivided into two central protein complexes,PRC1 and PRC2.PRC1 catalyzes H2AK119ub and PRC2catalyzes H3K27me1/2/3(Fursova et al.,2019).PRC1 is further categorized as CBX-containing canonical PRC1(c PRC1)and RYBP/YAF2-containing variant PRC1(v PRC1)(Blackledge and Klose,2021).
基金partially supported by the National Natural Science Foundation of China(41730528 and 41773091)Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(GML2019ZD0506)。
基金supported by the Chinese Postdoctoral Science Foundation (2022M710876)the Natural Science Foundation of Anhui Province (2108085MD133)+1 种基金the China Geological Survey (DD20190154 and DD20221689)the PI Project of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) (GML2020GD0802)。
文摘The early history of Earth is poorly understood,due to the lack of ancient rocks formed after the formation of the newborn Earth,especiallyfor thefirst 500 million years(Hadean Eon).To our knowledge,this period is the most geodynamically vigorous in the crustal evolution history of Earth[1],and is characterized by intense collision with meteorites and the formation of a global magma ocean(~4.41 Ga;cf.review article by Ref.[2]).
