Interrelationships between Length of the Day, Moon Distance, Phanerozoic Geodynamic Cycles, Tidal Dissipation and Earth’s Core: Review and Analysis

The rotation of the Earth and the related length of the day (LOD) are predominantly affected by tidal dissipation through the Moon and the growth of the Earth’s core. Due to the increased concentration of mass around the rotation axis of the spinning Earth during the growth of the core the rotation should have been accelerated. Controversially the tidal dissipation by the Moon, which is mainly dependent on the availability of open shallow seas and the kind of Moon escape from a nearby position, acts towards a deceleration of the rotating Earth. Measurements of LOD for Phanerozoic and Precambrian times open ways to solve questions concerning the geodynamical history of the Earth. These measurements encompass investigations of growth patterns in fossils and depositional patterns in sediments (Cyclostratigraphy, Tidalites, Stromatolites, Rhythmites). These patterns contain information on the LOD and on the changing distance between Earth and Moon and can be used as well for a discussion about the growth of the Earth’s core. By updating an older paper with its simple approach as well as incorporating newly published results provided by the geoscientific community, a moderate to fast growth of the core in a hot early Earth will be favored controversially to the assumption of a delayed development of the core in an originally cold Earth. Core development with acceleration of Earth’s rotation and the contemporaneous slowing down due to tidal dissipation during the filling of the ocean may significantly interrelate.

Construction of the Continental Asia in Phanerozoic:A Review

This is a review of the formation and tectonic evolution of the continental Asia in Phanerozoic.The continental Asia has formed on the bases of some pre-Cambrian cratons,such as the Siberia,India,Arabia,North China,Tarim,South China,and Indochina,through multi-stage plate convergence and collisional collages in Phanerozoic.The north-central Asia had experienced the expansion and subduction of the Paleo-Asian Ocean(PAO)in the early Paleozoic and the closure of the PAO in the late Paleozoic and early Mesozoic,forming the PAO regime and Central Asian orogenic belt(CAOB).In the core of the CAOB,the Mongol-Okhotsk Ocean(MOO)opened with limited expansion in the Early Permian and finally closed in the Late Jurassic–Early Cretaceous.The south-central Asia had experienced mainly multi-stage oceanic opening,subduction and collision evolution in the Tethys Ocean,forming the Tethys regime and Himalaya-Tibetan orogenic belt.In eastern Asia,the plate subduction and continental margin orogeny on western margin of the Pacific Ocean,forms the West Pacific regime and West Pacific orogenic belt.The PAO,Tethys,and West Pacific regimes,together with Precambrian cratons among or surrounding them,made up the major tectonic and dynamic systems of the continental Asia in Phanerozoic.Major tectonic events,such as the Early Paleozoic Qilian,Uralian,and Dunhuang orogeneses,the late Paleozoic East Junggar,Tianshan and West Junggar orogeneses,the Middle to Late Permian Ailaoshan orogeny and NorthSouth Lhasa collision,the early Mesozoic Indochina-South China and North-South China collisions,the late Mesozoic Mongolia-Okhotsk orogeny,Lhasa-Qiangtang collision,and intra-continental Yanshanian orogeny,and the Cenozoic IndoAsian,Arab-Asian,and West Pacific margin collisions,constrained the formation and evolution of the continental Asia.The complex dynamic systems have left large number of deformation features,such as large-scale strike-slip faults,thrustfold systems and extensional detachments on the continental Asia.Based on past tectonics,a future supercontinent,the Ameurasia,is prospected for the development of the Asia in ca.250 Myr.

Phanerozoic Paleomagnetism Characteristics of the Qomolangma Area in Tibet

This paper conducts systematic test research on the 2920 paleomagnetic directional samples taken from Ordovician-Paleogene sedimentary formation in the north slope of Qomolangma in south of Tibet and obtains the primary remanent magnetization component and counts the new data of paleomagnetism the times. Based on the characteristic remanent magnetization component, it calculates the geomagnetic pole position and latitude value of Himalaya block in Ordovician- Paleogene. According to the new data of paleomagnetism, it draws the palaeomagnetic polar wander curve and palaeolatitude change curve of the north slope of Qomolangma in Ordovician-Paleogene. It also makes a preliminary discussion to the structure evolution history and relative movement of Himalaya bloc. The research results show that many clockwise rotation movements had occurred to the Himalaya block in northern slope of Qomolangmain the process of northward drifting in the phanerozoic eon. In Ordovician-late Cretaceous, there the movement of about 20.0~ clockwise rotation occurred in the process of northward drifting. However, 0.4° counterclockwise rotation occurred from the end of late Devonian epoch to the beginning of early carboniferous epoch; 6.0° and 8.0° counterclockwise rotation occurred in carboniferous period and early Triassic epoch respectively, which might be related with the tension crack of continental rift valley from late Devonian period to the beginning of early carboniferous epoch, carboniferous period and early Triassic epoch. From the Eocene epoch to Pliocene epoch, the Himalaya block generated about 28.0° clockwise while drifting northward with a relatively rapid speed. This was the result that since the Eocene epoch, due to the continuous expansion of mid-ocean ridge of the India Ocean, the neo-Tethys with the Yarlung Zangbo River as the main ocean basin closed to form orogenic movement and the strong continent-continent collision orogenic movement of the east and west Himalayas generated clockwise movement in the mid- Himalaya area. According to the calculation of palaeolatitude data, the Himalaya continent- continent collusion orogenic movement since the Eocene epoch caused the crustal structure in Indian Plate- Himalaya folded structural belt- Lhasa block to shorten by at least 1000 km. The systematic research on the paleomagnetism of Qomolangma area in the phanerozoic eon provides a scientific basis to further research the evolution of Gondwanaland, formation and extinction history of paleo- Tethys Ocean and uplift mechanism of the Qinghai-Tibet Plateau.

Phanerozoic magmatism in the Proterozoic Cuddapah Basin and its connection with the Pangean supercontinent

Magmatic pulses in intraplate sedimentary basins are windows to understand the tectonomagmatic evolution and paleaoposition of the Basin.The present study reports the U-Pb zircon ages of mafic flows from the Cuddapah Basin and link these magmatic events with the Pangean evolution during late Carboniferous-Triassic/Phanerozoic timeframe.Zircon U-Pb geochronology for the basaltic lava flows from Vempalle Formation,Cuddapah Basin suggests two distinct Phanerozoic magmatic events coinciding with the amalgamation and dispersal stages of Pangea at 300 Ma(Late Carboniferous)and 227 Ma(Triassic).Further,these flows are characterized by analogous geochemical and geochronological signatures with Phanerozoic counterparts from Siberian,Panjal Traps,Emeishan and Tarim LIPs possibly suggesting their coeval and cogenetic nature.During the Phanerozoic Eon,the Indian subcontinent including the Cuddapah Basin was juxtaposed with the Pangean LIPs which led to the emplacement of these pulses of magmatism in the Basin coinciding with the assemblage of Pangea and its subsequent breakup between 400 Ma and 200 Ma.

Processes and causes of Phanerozoic tectonic evolution of the western Tarim Basin,northwest China

This paper addresses the Phanerozoic tectonic evolution of the western Tarim Basin based on an integrated stratigraphic,structural and tectonic analysis.P-wave velocity data show that the basin has a stable and rigid basement.The western Tarim Basin experienced a complex tectonic evolutionary history,and this evolution can be divided into six stages:Neoproterozoic to Early Ordovician,Middle Ordovician to Middle Devonian,Late Devonian to Permian,Triassic,Jurassic to Cretaceous and Paleogene to Quaternary.The western Tarim Basin was a rift basin in the Neoproterozoic to Early Ordovician.From the Middle Ordovician to Middle Devonian,the basin consisted of a flexural depression in the south and a depression that changed from a rift depression to a flexural depression in the north during each period,i.e.,the Middle-Late Ordovician and the Silurian to Middle Devonian.During the Late Devonian to Permian,the basin was a depression basin early and then changed into a flexural basin late in each period,i.e.,the Late Devonian to Carboniferous and the Permian.In the Triassic,the basin was a foreland basin,and from the Jurassic to Cretaceous,it was a downwarped basin.After the Paleogene,the basin became a rejuvenated foreland basin.Based on two cross sections,we conclude that the extension and shortening in the profile reflect the tectonic evolution of the Tarim Basin.The Tarim Basin has become a composite and superimposed sedimentary basin because of its long-term and complicated tectonic evolutionary history,highly rigid and stable basement and large size.

Crustal Accretion and Reworking within the Khanka Massif: Evidence from Zircon Hf Isotopes of Phanerozoic Granitoids

The Central Asian Orogenic Belt（CAOB）is one of the largest Phanerozoic accretionary orogen.（Windley et al.,1990,2007;Jahn et al.,2000a,b,c;Yakubchuk,2002,2004;Xiao et al.,2003,2004）.It is the optimal study area for revealing the accretion and reworking processes of the continental crust.The Khanka Massif is located in the most eastern part of the CAOB,and mainly crops out in the territory of Russia,with a small segment in NE China.In addition,a large number of multi-stage granitic rocks are formed in geological evolution in this area,recording amounts of information about crustal accretion and reworking processes（De Paolo et al.,1991;Rudnick,1995;Wu et al.,2011）.In view of this,this paper uses the spatial-temporal variations of trace elements and zircon Hf isotopic compositions of phanerozoic granitoids within the Khanka Massif as a case to reveal the crustal accretion and reworking processes of micro continental massifs from the orogenic belt,further to understand the formation and evolution processes and mechanisms of the global continental crust.According to the statistics of zircon U-Pb ages of granitoids in the Khanka Massif,indicate that the granitic magmatisms in the Khanka Massif have eleven peaks:492 Ma,460 Ma,445Ma,430Ma,425Ma,302Ma,287Ma,258Ma,249 Ma,216Ma and 213Ma,it can be divided into eight main stages:Late Cambrian,Middle-Late Ordovician,Middle Silurian,Late Carboniferous,EarlyPermian,Middle-Late Permian—Early Triassic,Late Triassic-Early Jurassic,Early Cretaceous.The Phanerozoic granitoids in Khanka massif are selectedinthispaperasasuiteof granodiorite-monzogranite-syenogranite.TheSi O2contents of the Phanerozoic granitoids exceed 65%,and has high Al2O3,low Mg#,TFe2O3,Cr,Co and Ni contents.This suggests that mixture with mantle-derived magma did not occur,and it should be a typical crustal source（Lu and Xu,2011）.Combined with evident characteristics of light rare-earth elements（LREEs）and large ion lithophile elements（LILEs）enrichment,and heavy rare-earth elements（HREEs）and high field-strength elements（HFSEs）loss,we suggest that the primary magma was derived by partial melting of lower crustal material（Xu et al.,2009）,and geochemical properties of the Phanerozoic granitoids essentially reflect the nature of the magmatic source region.According to the temporal variation of zircon Hf isotopic data of Phanerozoic granitioids,zircon Hf isotopic compositions of Phanerozoic granitoids have a obvious correlation with age.With the decrease of formation time ofthePhanerozoicgranitoids（Late Cambrian;iddle-LateOrdovician;iddle Silurian;arlyPermian;iddle-LatePermian–Early Triassic;ate Triassic-Early Jurassic）,εHf（t）values of zircons gradually increase,whereas their TDM2 ages gradually decrease（Paleoproterozoic–Neoproterozoic）,suggesting that the generation of granitic magmas from the Khanka Massif could have experienced the change from the melting of the ancient crust to the juvenile crust during Paleozoic to Mesozoic.According to the sample location,it can be found thatεHf（t）values of Phanerozoic granitoids have the tendency to decrease with latitude increase,showing that components of the ancient continental crust gradually increase from south to north.However,at the same latitude range,theεHf（t）values of Phanerozoic granitoids also inconsistent.Taken together,these differences reveal the horizontal and vertical heterogeneity of the lower continental crust within the Khanka Massif.According to the relative probability of two-stage model（TDM2）ages of zircon Hf isotope from Phanerozoic granitoids within the Khanka massif,it could be divided into three stages:（1）Late Paleoproterozoic（2）Mesoproterozoic（3）Neoproterozoic.It reveals that the main part of the continental crust within the Khanka MassifwereformedinLate Paleoproterozoic–Neoproterozoic.The Phanerozoic granitoids in the Khanka Massif reworked from the source rockswithdifferent ages（Paleoproterozoic–Mesoproterozoic–Neoproterozoic）.

Power-law patterns in the Phanerozoic sedimentary records of carbon, oxygen, sulfur,and strontium isotopes

Power-law patterns appear in a variety of natural systems on the modern Earth;nevertheless,whether such behaviors appeared in the deep-time environment has rarely been studied. Isotopic records in sedimentary rocks, which are widely used to reconstruct the geological/geochemical conditions in paleoenvironments and the evolutionary trajectories of biogeochemical cycles, offer an opportunity to investigate power laws in ancient geological systems. In this study, I focus on the Phanerozoic sedimentary records of carbon, oxygen, sulfur, and strontium isotopes, which have well documented and extraordinarily comprehensive datasets. I perform statistical analyses on these datasets and show that the variations in the sedimentary records of the four isotopes exhibit power-law behaviors. The exponents of these power laws range between 2.2 and 2.9;this narrow interval indicates that the variations in carbon, oxygen, sulfur, and strontium isotopes likely belong to the same universality class, suggesting that these systematic power-law patterns are governed by universal, scale-free mechanisms. I then derive a general form for these power laws from a minimalistic model based on basic physical principles and geosystem-specific assumptions, which provides an interpretation for the power-law patterns from the perspective of thermodynamics. The fundamental mechanisms regulating such patterns might have been ubiquitous in paleoenvironments, implying that similar power-law behaviors may exist in the sedimentary records of other isotopes.

Apparent polar wander path and tectonic movement of the North China Block in Phanerozoic

The results on the Early Paleozoic from the North China Block (NCB) are reported, and a series of reliable poles are selected from the available Phanerozoic data, based on the conventional reliability criteria, e.g. the number of samples, the uncertainty limit, any suspected incomplete demagnetization or overprint and field test (including fold, reversal, conglomerate tests). Especially, paleopole data is excluded if the sampling area suffered from the tectonic (e.g. rotation) and thermal effects. A new Phanerozoic apparent polar wander (APW) path for the NCB is compiled, and its tectonic evolution is discussed.

Impact of changing atmospheric CO_2 concentrations over the Phanerozoic on stomatal parameters of vascular land plants

A novel and multi-disciplinary subject involving the relationships between changes in atmospheric CO2 concentration throughout the geological history and features of plant anatomy is reviewed. Particular attention will be given to stomatal parameters （stomatal density and stomatal index） which are recorded at a cellular level in fossil plants and the relationships of these observable parameters to earth life history and global environmental change. Trends of atmospheric CO2 concentrations during the Phanerozoic period are briefly introduced and recent conceptual advances in understanding the causal mechanisms for changes in stomatal parameters of land vascular plants are considered, In addition, some of the inherent problems and limitations of this kind of work are discussed and future research directions are presented.

Geodynamic evolution of the Earth over the Phanerozoic:Plate tectonic activity and palaeoclimatic indicators

During the last decades, numerous local reconstructions based on field geol- ogy were developed at the University of Lausanne （UNIL）. Team members of the UNIL partici- pated in the elaboration of a 600 Ma to present global plate tectonic model deeply rooted in geological data, controlled by geometric and kinematic constraints and coherent with forces acting at plate boundaries. In this paper, we compare values derived from the tectonic model （ages of oceanic floor, production and subduction rates, tectonic activity） with a combination of chemical proxies （namely CO2, 87Sr/86Sr, glaciation evidence, and sea-level variations） known to be strongly in- fluenced by tectonics. One of the outstanding results is the observation of an overall decreas- ing trend in the evolution of the global tectonic activity, mean oceanic ages and plate velocities over the whole Phanerozoic. We speculate that the decreasing trend reflects the global cooling of the Earth system. Additionally, the parallel between the tectonic activity and CO2 together with the extension of glaciations confirms the generally accepted idea of a primary control of CO2 on climate and highlights the link between plate tectonics and CO2 in a time scale greater than 107 yr. Last, the wide variations observed in the reconstructed sea-floor production rates are in contradiction with the steady-state model hypothesized by some.

Crustal Accretion and Reworking within the Khanka Massif： Evidence from Hf Isotopes of Zircons in Phanerozoic Granitoids

This paper presents a synthesis and analysis of geochronological, geochemical, and zircon Hf isotopic data of Phanerozoic granitoids within the Khanka massif, with the aim of revealing the ac- cretion and reworking processes of continental crust within the massif. Zircon U-Pb dating indicates that Phanerozoie granitic magmafism within the Khanka massif can be subdivided into eight stages： Late Cambrian, Middle-Late Ordovieian, Middle Silurian, Late Carboniferous, Early Permian, Middle--Late Permian to Early Triassic, Late Triassic-Early Jurassic, and Early Cretaceous. The zircon Hf isotopic compositions reveal that crustal accretionary events took place mainly in the Mesoprotero- zoie and Neoproterozoic. Through time, the zircon eHf（t） values gradually increase, indicating that the Phanerozoie granitic magmas were derived from the melting of progressively less ancient and more ju- venile crust. The zircon eHdt） values exhibit a gradual decrease with the increases in latitude, which im- plies that the amounts of ancient crustal components within the lower continental crust of the Khanka massif increased from south to north. At the same latitude range, the zircon Hf isotopic compositions also display some variations. We conclude, therefore, that significant horizontal and vertical heteroge- neities existed in the lower continental crust of the Khanka massif during the Phanerozoic.

Uranium Provinces in China

Three uranium provinces are recognized in China, the Southeast China uranium province, the Northeast China-Inner Mongolia uranium province and the Northwest China (Xinjiang) uranium province. The latter two promise good potential for uranium resources and are major exploration target areas in recent years. There are two major types of uranium deposits: the Phanerozoic hydrothermal type (vein type) and the Meso-Cenozoic sandstone type in different proportions in the three uranium provinces. The most important reason or prerequisite for the formation of these uranium provinces is that Precambrian uranium-enriched old basement or its broken parts (median massifs) exists or once existed in these regions, and underwent strong tectonomagmatic activation during Phanerozoic time. Uranium was mobilized from the old basement and migrated upwards to the upper structural level together with the acidic magma originating from anatexis and the primary fluids, which were then mixed with meteoric water and resulted in the formation of Phanerozoic hydrothermal uranium deposits under extensional tectonic environments. Erosion of uraniferous rocks and pre-existing uranium deposits during the Meso-Cenozoic brought about the removal of uranium into young sedimentary basins. When those basins were uplifted and slightly deformed by later tectonic activity, roll-type uranium deposits were formed as a result of redox in permeable sandstone strata.

Four billion years of ophiolites reveal secular trends in oceanic crust formation

We combine a geological, geochemical and tectonic dataset from 118 ophiolite complexes of the major global Phanerozoic orogenic belts with similar datasets of ophiolites from 111 Precambrian greenstone belts to construct an overview of oceanic crust generation over 4 billion years. Geochemical discrimi- nation systematics built on immobile trace elements reveal that the basaltic units of the Phanerozoic ophiolites are dominantly subduction-related （75%）, linked to backarc processes and characterized by a strong MORB component, similar to ophiolites in Precambrian greenstone sequences （85%）. The remaining 25% Phanerozoic subduction-unrelated ophiolites are mainly （74%） of Mid-Ocean-Ridge type （MORB type）, in contrast to the equal proportion of RiftlContinental Margin, Plume, and MORB type ophiolites in the Precambrian greenstone belts. Throughout the Phanerozoic there are large geochemical variations in major and trace elements, but for average element values calculated in 5 bins of 100 million year intervals there are no obvious secular trends. By contrast, basaltic units in the ophiolites of the Precambrian greenstones （calculated in 12 bins of 250 million years intervals）, starting in late Paleo- to early Mesoproterozoic （ca. 2.0-1.8 Ga）, exhibit an apparent decrease in the average values of incom- patible elements such as Ti, P, Zr, Y and Nb, and an increase in the compatible elements Ni and Cr with deeper time to the end of the Archean and into the Hadean. These changes can be attributed to decreasing degrees of partial melting of the upper mantle from HadeanJArchean to Present. The onset of geochemical changes coincide with the timing of detectible changes in the structural architecture of the ophiolites such as greater volumes of gabbro and more common sheeted dyke complexes, and lesser occurrences of ocelli （varioles） in the pillow lavas in ophiolites younger than 2 Ga. The global data from the Precambrian ophiolites, representative of nearly 50% of all known worldwide greenstone belts provide significant clues for the operation of plate tectonic processes in the Archean.

洋盆封闭后我们有时所忽视的东西:以澳大利亚东部的显生宇为例(英文)

The prevailing ’consensus’ explanation for Phanerozoic development of eastern Australia envisages a ’retreating accretionary orogen’ in which episodic slab retreat resulted in development of offshore island arcs in front of marginal basins.

Relation of Tethys Ocean Subduction, Collision and Closure with Regional Metamorphism, Volcanism and Mineralization Exemplified on the Eurasian Active Margin

The geodynamic development of Eurasian active margin is related to subduction,collision and closure of Tethys Ocean.It is divided on pre-collision and post-collision stages.The pre-collision development controlled by subduction,whereas post-collision related by orogenesis,granodiorite magmatism gold base and trace metals(Sb,W,Mo and Hg)metallogeny.The mentioned trace metals association is the geochemical indicator of first stage of post-collision development.The second stage revealed in andesite basalt,shoshonite,olivine basalt and tholeiite volcanic activity.Pre-collision stage is controlled by steady state subduction related with metamorphism and calc-alkaline volcanic activity in subaqual and island conditions of island arc setting.It is lately with steepening of subducting slab and incursion of mantle diapir transferred in interarc-backarc and minor ocean setting with shoshonite-trachyandesite and alkali olivine basalt and tholeiite volcanism and later with ophiolite volcanism,dunite-peridotite magmatism and Cu-pyrite mineralization of minor ocean setting.The pre-collision stage is developed temporally and spacially along dipping of subducted slab in the island arc setting transferring in the backarc-interarc and minor ocean settings.The similar transferring occurs laterally to dipping of slab and ascending succession.The alternation of settings shown the cycling along dipping spatial and temporal alternation of island arc,backarc and minor ocean settings.Laterally to dipping alternation is only spatial,whereas in ascending succession cycling is only temporal,localized spacially.The pre-collision development occurs in subaqual condition,whereas related to orogenesis post-collision development is mainly subaerial.

Seawater Temperature and Dissolved Oxygen over the Past 500 Million Years

Ocean temperature and dissolved oxygen concentrations are critical factors that control ocean productivity, carbon and nutrient cycles, and marine habitat. However, the evolution of these two factors in the geologic past are still unclear. Here, we use a new oxygen isotope database to establish the sea surface temperature(SST) curve in the past 500 million years. The database is composed of 22 796 oxygen isotope values of phosphatic and calcareous fossils. The result shows two prolonged cooling events happened in the Late Paleozoic and Late Cenozoic, coinciding with two major ice ages indicated by continental glaciation data, and seven global warming events that happened in the Late Cambrian, Silurian–Devonian transition, Late Devonian, Early Triassic, Toarcian, Late Cretaceous, and Paleocene–Eocene transition. The SSTs during these warming periods are about 5–30 °C higher than the present-day level. Oxygen contents of shallow seawater are calculated from temperature, salinity, and atmospheric oxygen. The results show that major dissolved oxygen valleys of surface seawater coincide with global warming events and ocean anoxic events. We propose that the combined effect of temperature and dissolved oxygen account for the long-term evolution of global oceanic redox state during the Phanerozoic.