the tectonics of china [data, maps and evolution] by tianfeng wan

5
Geosciences Journal Vol. 16, No. 1, p. 85 89, March 2012 DOI 10.1007/s12303-012-0008-5 The Association of Korean Geoscience Societies and Springer 2012 Book review The Tectonics of China [Data, Maps and Evolution] By Tianfeng Wan, Higher Education Press, Beijing and Springer- Verlag, Berlin, 2010, pp. xiv + 501, ISBN-13 978-3642118661, Price: 139.00 (EUR) or 159.00 (USD). Professor T. Wan of the School of Earth Sciences and Resources, China University of Geosciences (Beijing), has finally published this brilliant work. Professor Wan has syn- thesized the prominent works of geoscientists on the tec- tonics of the Chinese continent since the application of the theory of plate tectonics in the early 1970s and the effects of his masterful and creative steering is evident in this syn- thesis. The ca. 500 page book is enriched with data, maps and 156 figures (52 of which are in color). This book is highly recommended as it provides a luminous synthesis of the most current and up-to-date work of the geology of China. Wan originally wrote and published the essential part of this volume in Chinese which was subsequently pub- lished by the Geological Publishing House in Beijing in 2004. The current English edition provides the most up-to- date synopsis of the life works of Professor Wan. In the introduction (Chapter 1), Professor Wan emphasizes the concept of tectono-stratigraphic units, each of which are distinguished by a unique style of deformation developed over a particular tectonic period. For example, Wan dem- onstrates that folding style and axis orientation change in wsucceeding tectono-stratigraphic units. The boundary of a tectono-stratigraphic unit is taken as a major break in sed- imentation, i.e., a regional angular unconformity that sep- arates the tectono-stratigraphic units; and the geologic time of a given tectono-stratigraphic unit represents the ‘tectonic period’. Tectonic periods in China thus, demarcate time intervals defined by regional tectonic syntheses of China and the author defines 17 such tectonic periods in China (Table 1.3). The concept of alternating phases of crustal shortening (compression) and extension for a particular region is found in almost all of his chapters accompanied by a dis- cussion on the means of quantitative measurement. Chapter 2: The tectonics of Archean and Paleoprotero- zoic (before 1.8 Ga). The Archean (4.62.5 Ga) and the Paleoproterozoic (2.51.8 Ga) occupy more than 60% of Earth history, but rocks formed during this interval com- prise only about 58% of the surface area of China. These rocks dominate the lower crust, constitute ~80% of the con- tinental crust and represent reworked products mainly of the Neoarchean-Paleoproterozoic (2.81.8 Ga). Presumably any oceanic proto-crustal material which once existed has long been subducted and recycled back into the mantle. Thus, such a limitation allowed for the detailed dis- cussion of only three tectono-stratigraphic units: the Pale- oarchean (3.63.2 Ga) Qianxi; the Mesoarchean (3.22.8 Ga) Fuping; and the Neoarchean (2.82.5 Ga) Wutai . Proto-con- tinental block formation and continental cratonization were realized during these tectonic periods. An angular unconformity separating the Archean and the Proterozoic developed over the Sino-Korean Plate. The Pale- oproterozoic (2.51.8 Ga) Luliang Tectonic Period (known also as the ‘Huto Period’) witnessed rift-related sedimenta- tion and amalgamation and the subsequent unification of crystalline basement of the Sino-Korean continental proto- plate prior to 1.8 Ga. The Luliang Tectono-stratigraphic Unit is typically developed in the Mt. Luliang area, Shansi Prov- ince. The Huto unit long recognized in the Wutai area is per- haps analogous to the Luliang Tectono-stratigraphic Unit. Chapter 3 deals with Tectonics of the Mesoproterozoic- Early Cambrian (1.8 Ga513 Ma). The Early Cambrian ‘Sin- ian Tectonic Period’ (as coined by the author) has been included because continued sedimentation from the Sinian to the Cambrian Systems (the base of the Cambrian, ca. 543 Ma) and a hiatus in deposition between the Early and Mid- dle epochs of the Cambrian is evident in many regions of China. Chinese Tectonic Periods discussed here include: (1) Mesoproterozoic Changcheng (1.81.4 Ga); (2) Mesoprot- erozoic Jixian (1.41.0 Ga); (3) Neoproterozoic Qingbaikou (Jinning) (1.0 Ga 800 Ma); (4) Neoproterozoic Nanhua (Cryo- genian) (800680 Ma); and (5) Latest Neoproterozoic-Early

Upload: ki-hong-chang

Post on 25-Aug-2016

212 views

Category:

Documents


0 download

TRANSCRIPT

Geosciences JournalVol. 16, No. 1, p. 85 − 89, March 2012DOI 10.1007/s12303-012-0008-5ⓒ The Association of Korean Geoscience Societies and Springer 2012

Book review

The Tectonics of China [Data, Maps and Evolution] ByTianfeng Wan, Higher Education Press, Beijing and Springer-Verlag, Berlin, 2010, pp. xiv + 501, ISBN-13 978-3642118661,Price: 139.00 (EUR) or 159.00 (USD).

Professor T. Wan of the School of Earth Sciences andResources, China University of Geosciences (Beijing), hasfinally published this brilliant work. Professor Wan has syn-thesized the prominent works of geoscientists on the tec-tonics of the Chinese continent since the application of thetheory of plate tectonics in the early 1970s and the effectsof his masterful and creative steering is evident in this syn-thesis. The ca. 500 page book is enriched with data, mapsand 156 figures (52 of which are in color). This book ishighly recommended as it provides a luminous synthesis ofthe most current and up-to-date work of the geology ofChina. Wan originally wrote and published the essential partof this volume in Chinese which was subsequently pub-lished by the Geological Publishing House in Beijing in2004. The current English edition provides the most up-to-date synopsis of the life works of Professor Wan.

In the introduction (Chapter 1), Professor Wan emphasizesthe concept of tectono-stratigraphic units, each of which aredistinguished by a unique style of deformation developedover a particular tectonic period. For example, Wan dem-onstrates that folding style and axis orientation change in

wsucceeding tectono-stratigraphic units. The boundary of atectono-stratigraphic unit is taken as a major break in sed-imentation, i.e., a regional angular unconformity that sep-arates the tectono-stratigraphic units; and the geologic timeof a given tectono-stratigraphic unit represents the ‘tectonicperiod’. Tectonic periods in China thus, demarcate timeintervals defined by regional tectonic syntheses of Chinaand the author defines 17 such tectonic periods in China(Table 1.3). The concept of alternating phases of crustalshortening (compression) and extension for a particular regionis found in almost all of his chapters accompanied by a dis-cussion on the means of quantitative measurement.

Chapter 2: The tectonics of Archean and Paleoprotero-zoic (before 1.8 Ga). The Archean (4.6−2.5 Ga) and thePaleoproterozoic (2.5−1.8 Ga) occupy more than 60% ofEarth history, but rocks formed during this interval com-prise only about 58% of the surface area of China. Theserocks dominate the lower crust, constitute ~80% of the con-tinental crust and represent reworked products mainly of theNeoarchean-Paleoproterozoic (2.8−1.8 Ga).

Presumably any oceanic proto-crustal material which onceexisted has long been subducted and recycled back into themantle. Thus, such a limitation allowed for the detailed dis-cussion of only three tectono-stratigraphic units: the Pale-oarchean (3.6−3.2 Ga) Qianxi; the Mesoarchean (3.2−2.8 Ga)Fuping; and the Neoarchean (2.8−2.5 Ga) Wutai. Proto-con-tinental block formation and continental cratonization wererealized during these tectonic periods.

An angular unconformity separating the Archean and theProterozoic developed over the Sino-Korean Plate. The Pale-oproterozoic (2.5−1.8 Ga) Luliang Tectonic Period (knownalso as the ‘Huto Period’) witnessed rift-related sedimenta-tion and amalgamation and the subsequent unification ofcrystalline basement of the Sino-Korean continental proto-plate prior to 1.8 Ga. The Luliang Tectono-stratigraphic Unitis typically developed in the Mt. Luliang area, Shansi Prov-ince. The Huto unit long recognized in the Wutai area is per-haps analogous to the Luliang Tectono-stratigraphic Unit.

Chapter 3 deals with Tectonics of the Mesoproterozoic-Early Cambrian (1.8 Ga−513 Ma). The Early Cambrian ‘Sin-ian Tectonic Period’ (as coined by the author) has beenincluded because continued sedimentation from the Sinianto the Cambrian Systems (the base of the Cambrian, ca. 543Ma) and a hiatus in deposition between the Early and Mid-dle epochs of the Cambrian is evident in many regions ofChina. Chinese Tectonic Periods discussed here include: (1)Mesoproterozoic Changcheng (1.8−1.4 Ga); (2) Mesoprot-erozoic Jixian (1.4−1.0 Ga); (3) Neoproterozoic Qingbaikou(Jinning) (1.0 Ga−800 Ma); (4) Neoproterozoic Nanhua (Cryo-genian) (800−680 Ma); and (5) Latest Neoproterozoic-Early

86 Ki-Hong Chang

Cambrian Sinian (680−513 Ma).During the Changcheng Period (1.8−1.4 Ga), rift basins

developed in many places within the Sino-Korean Proto-plate leading to deposition of earliest sedimentary cover whichnow blankets crystalline basement. The extent of Mesopro-terozoic rifting near Beijing and associated ore genesis andshallow marine sedimentation are shown in Figures 3.3, 3.4and 3.5. The Qinling-Dabie Block underwent extensionalfracturing in the Early Mesoproterozoic and collision andshortening in the last phase of the Mesoproterozoic (~1,000Ma). Recently acquired isotope dates from metamorphicand granitic rocks of the Qinling-Dabie Block suggest apeak of metamorphic and magmatic activity throughout thefinal phase (~1,000 Ma) of the Jixian Period.

The Mesoproterozoic marks the timing of sedimentarycovering of the consolidated Sino-Korean Protoplate andthe amalgamation of the Yangtze Plate. The Sibao TectonicEvent (ca. 1,000 Ma) at the end of the Jixian Period was themost important tectonic episode in South China and reachedits peak at ~1,050 Ma. The Sibao Tectonic Event witnessedthe subduction of the South Yangtze Plate and its conse-quent collision with the North Yangtze Plate to ultimatelyform the Yangtze Plate at the end of the Mesoproterozoic.The Jiangnan Collision Zone (JN) of the Yangtze Platedelineates a suture zone that formed during the Late Qing-baikou period. The suture records widespread granitic mag-matism at 846 Ma (Rb-Sr age) and plate-shortening at 5.9−7.6 cm/year).

In the Mesoproterozoic, the presence of an ocean betweenthe ‘tin-rich’ South Yangtze Plate and the ‘tungsten-rich’Cathaysian Plate was probable as evidenced by continentalslope and bathyal turbidite deposits which occurred on themargins of the Cathaysian and Yangtze Plates. The diver-gence in metallogenetic characteristics between the Cathay-sian and Yangtze Plates may reflect differences in the originalcomposition of the planetesimal groups that formed the pro-toplates.

Although the Neoproterozoic Qingbaikou Tectonic Period(1,000−800 Ma) of China was originally defined in NorthChina, the standard section and typical tectonic events ofthis period actually occur at Jinning, Yunnan, South China,and are therefore sometimes called the ‘Jinning TectonicPeriod’. The Yangtze Plate developed a unified crystallinebasement in the Qingbaikou Period by collision of the con-tinental blocks and final amalgamation to form the base-ment. In contrast to the Yangtze and Cathaysia plates therewas no obvious rock deformation in the whole Sino-KoreanPlate during the Qingbaikou Tectonic Period (1,000−800 Ma).The most intense tectonic events of the Qingbaikou Periodaffected the Yangtze and Cathaysia plates, as witnessed bymetamorphic and sedimentary systems which underwentintense folding on E-W trending axes and N-S shortening.In the last 20 years the Shaoxing-Shiwandashan CollisionZone has been intensively studied; isotope ages (1034−806

Ma) from magmatic rocks suggest that collision and earlyamalgamation of the Yangtze and the Cathaysia platesoccurred along the Shaoxing-Shiwandashan Collision Zoneduring the Qingbaikou Period. Isotope ages ranging from987−796 Ma indicate that magmatism and metamorphismoccurred within the Qinling-Dabie Block during the Qing-baikou Period. Many basic igneous bodies within the Qin-ling-Dabie Block were metamorphosed under ultra-highpressure to eclogite with some bodies recording Triassic(221−244 Ma) UHPM overprints.

Inclusive of the Sturtian glacial event at 720 Ma, the Nan-hua Period (800−680 Ma), correlates roughly with the glo-bally recognized Cryogenian Period (850−680 Ma) and marksan interval of widespread extension and rifting of continen-tal blocks in China. In this period, a notably terrestrial sed-imentary cover was deposited on the crystalline basementof the Yangtze Plate as evidenced by the Nanhua sedimen-tary sequence that overlies the metamorphic strata with anangular unconformity and which in turn is disconformablyoverlain by the Sinian strata. In contrast, the greater part ofthe Sino-Korean Plate was sub aerial and subject to erosionas evidenced by fault depressions inherited from those ofthe Qingbaikou Period in the eastern part of the Plate. Gla-cial tillites of the Nantuo Formation were deposited on theYangtze and the Tarim plates in the Nanhua Period at a timewhen no tillites were deposited on the Sino-Korean plate. Incontrast, the Sinian tillites were deposited along the south-ern margins of the Sino-Korean plate. This suggests that the‘Snow-Ball Earth’ hypothesis has some problems with thestratigraphic correlation.

The Sinian Period (680−513 Ma) of the present work, theequivalent of the Late Neoproterozoic Ediacaran Epoch(International Commission on Stratigraphy, 2004) plus theEarly Cambrian, was a time of tectonic stability in most ofChina though the Pan-African Tectonic Event affected partsof China where a unified crystalline basement was estab-lished during the Sinian Period. Continuous sedimentationoccurred astride the Precambrian-Cambrian boundary inmany areas of China. During the Precambrian Sinian (680−543 Ma), limestone was deposited in South China (the Dous-hantuo and Dengying Formations) and shallow marine clas-tic sediments were deposited partly over the Sino-KoreanPlate (Fig. 3.10).

During the Middle Cambrian-Early Devonian age (513−397 Ma), the Early Paleozoic Qilian Tectonic Period of Chinahas been established based on the tectono-stratigraphic unitbounded by frequently observed unconformities at the baseof the Middle Cambrian and at the top of the Lower Devo-nian in China. During the Qilian Period, the Cathaysian Platefounded a unified crystalline basement, the South YangtzePlate experienced intra-plate deformation, and the Altay-Middle Mongolia-Ergun collision belt and some other dis-tinctive geological developments were made. Within the Sino-Korean Plate, the Late Early Cambrian marine transgres-

Book review: The Tectonics of China 87

sion occurred after an interval of long-term Neoproterozoic-Early Cambrian erosion and the Middle Cambrian is foundonly in the central Sino-Korean Plate. At the end of theEarly Paleozoic, intra-plate folding occurred in the SouthYangtze Plate for reasons that remain unclear.

In the Middle Devonian-Middle Permian (397−260 Ma),the Tianshan Tectonic Period according to this book repre-sents the approximate equivalent of the formerly termedVariscan or Hercynian Period, but is named anew by theauthor based on Chinese geological data. In this period, theTianshan-South Hinganling Collision Belt was formed andthe Emeishan Mantle plume developed. During the Paleo-zoic, the Chinese blocks were always located in the south-ern hemisphere at mid to low latitudes along the northernmargin of Gondwana, with shelf sedimentation in a cold,temperate climate. At the end of the Late Paleozoic, largescale extension occurred in the southwestern part of the SouthYangtze Plate as a result of the rising Emeishan Plume.

As defined in this volume, the Indosinian Tectonic Periodin China is of Late Permian-Triassic (260−200 Ma) age. Thetectonism of this period is regarded as the most intensiveand extensive one in the Phanerozoic history of China andsurrounding regions. Originally recognized in Vietnam, theIndosinian movement has been regarded by many Chinesegeologists as the most important tectonic event in the for-mation of the Chinese continent. In the Indosinian Peninsulaand South China, the tectonic event is generally represented byan angular unconformity between Middle Triassic andUpper Triassic rocks, but recently, the Indosinian TectonicPeriod has been extended to cover all tectonic events fromthe Late Permian to the end Triassic. On the Chinese con-tinent major collisions and deformations occurred both atthe end of the Middle Triassic and at the end of the Late Tri-assic. There is generally a continuous sedimentary sequencein the transition from the Permian to the Triassic systems inspite of a catastrophic faunal and floral extinction (morethan 90% families/species).

The Indosinian tectonic system is represented by inter-plate collision zones such as the Qinling-Dabie, Lancangjiang,Jinshajiang and others. According to regional relationships,the collision in general began in the Late Permian and con-tinued into the Late Triassic, climaxing at the end of theMiddle Triassic. But the peak of the Indosinian collisionwas during the Middle-Late Triassic at 228−200 Ma. TheLangcangjiang Collision Zone (1 in Fig. 6.3) was the col-lision-amalgamation zone between Gondwana (with LatePaleozoic glacial deposits and cold-water faunas) and Chi-nese (with warm water faunas) continental blocks.

In the Early Triassic and in the early Middle Triassic, shallowmarine carbonates were deposited upon the Yangtze Platewhereby shallow marine clastic carbonates were depositedupon the Cathaysian Plate. But the Middle Triassic collisionof the Yangtze and Cathaysian plates resulted in upliftedland areas over the southeastern part of Yangtze and adja-

cent Cathaysia. In the Late Triassic, some fluvial-lacustrineclastics were deposited upon the Yangtze Plate while theCathaysian Plate was defined by mountain lowlands andhills. The Shaoxing-Shiwandashan Collision Zone betweenthe Yangtze and Cathaysian plates went through three col-lisions: in the Jinning period (~800 Ma); at the end of theEarly Paleozoic; and finally at about the end of the MiddleTriassic. A proposition by M.Z. Sun et al. (1990) suggeststhat collisions of different times took place in different partsof the Shaoxing-Shiwandashan zone: namely, near Shaox-ing in the Jinningian; the middle section of the zone in theend of the Early Paleozoic; and finally the southwesternsection (near Shiwandashan) in the Indosinian.

This chapter deals with Indosinian tectonism, indentationalcollision and crocodile tectonics which have been high-lighted on the basis of deep seismic data which verifiessuch processes. Indentation and crocodile tectonics (wedgetectonics) illustrate that while the upper crust obducts, thelower crust plus the upper mantle subducts. In the Qinling-Dabie Collision Zone between the Sino-Korean and theYangtze plates, the Luonan-Fangchang Collision Zone (10in Fig. 6.3) is truncated by the Tancheng-Lujiang sinistralstrike-slip fault zone, which continues as the Zhucheng-Qingdao-Rongcheng Collision Zone (11 in Fig. 6.3) as faras the Yellow Sea. The Qinling-Dabie Zone collision-amal-gamation event was completed in the late Triassic as sug-gested by isotopic data from syn-collisional metamorphicand magamtic rocks yielding ages of 240−210 Ma. TheQinling-Dabie Collision Zone underwent more intensedeformation than in other collision zones; the high to UHPmetamorphic rocks, including eclogite with quartz, coesite,micro-diamonds and glaucophane schists in melange mayrepresent residual sheets of Yangtze Plate upper mantle.The isotopic ages of UHPM rocks are concentrated in threeperiods: Neoproterozoic (800 Ma); Early Devonian (400Ma); and Middle Triassic (221−244 Ma). A reliable workconcluded that the metamorphic rocks formed deep in themantle at 245−240 Ma and were uplifted at 240−230 Maover a distance of 75−375 km from the mantle to the middlecrust. In a study using seismic tomography, authors identi-fied a crocodile tectonics regime within the Jiaonan( Shan-dong Peninsula) Collision Zone: they found that at a depthof 16−25 km, the crust of the Sino-Korean Plate penetratedsouthwardly about 80 km into the crust and mantle of theYangtze Plate.

The Yanshanian Tectonic Period as defined here coversthe Jurassic Period and the earliest Early Cretaceous Epoch(200−135 Ma) corresponding to the ‘Early YanshanianPeriod’ of Bureaus of Geology and Mineral Resources ofProvinces (1984−1993). First recognized in the Yanshanarea near Beijing, the Yanshanian movement was the Juras-sic tectonism as described by Weng W.H. (1927, 1929), butwas later extended to the Cretaceous by several authors.The author of this book assumes the position as that of the

88 Ki-Hong Chang

Jurassic Yanshanian. In the Yanshan area, the product ofthis tectonic period was the Lower Jurassic (mainly coal-bearing) formations, Middle Jurassic formations, Upper Juras-sic (mainly terrestrial) clastic formations and the mainlyacidic-volcanic Yixian Foramtion that forms the base of theLower Cretaceous Series.

Since most of the continental blocks that make up theChinese continent were amalgamated in the Triassic, theJurassic China behaved as a single continental plate andunderwent a counterclockwise rotation of 20 to 30°. Themost important tectonic event during the Yanshanian Tec-tonic Period was the crustal rotation of the Chinese conti-nent which was caused by westward migration, subductionand compression of the Okhotsk (a segment of the Amer-ican Plate) and Izanagi Plate. From the Triassic to Jurassicperiods the southern Korean Peninsula rotated 20 degreescounter-clockwise (Kim and Van der Voo, 1990) and theYangtze Plate also rotated similarly. The counterclockwiserotation of many areas of the Chinese continent and the sur-rounding regions affected the intra-plate deformation of theEast Asian continent during the Yanshanian Period. The rota-tion of the Chinese continent catalyzed by the AmericanPlate was the major cause of development of detachmentsand thrusts in the middle and lower crust under the Neo-cathaysian Tectonic System, followed by widespread tec-tono-magmatism in the above transitional lithosphere ofeastern China. The westward collision of North Americaand subsequent compression caused strong deformation ineastern Siberia and formed the Wandashan Collision Zonein Northeast China and also instigated movement along theTanakura Tectonic Line in Japan. At the end of the Jurassic,there was a radial migration of the plates: the Izanagi Platemoved northwestward; the Farallon Plate moved northeast-ward; the Phoenix Plate moved southeastward and thePacific Plate propagated southwestward. Such radial platemovements were probably caused by a mantle super-plume.The northwestward subduction of the Izanagi Plate wassubordinate in controlling the Chinese tectonics.

The Yanshanian Tectonic Period was the time of prolif-erous magmatic activity, its product outcropping over about25% of China. Jurassic granitic and volcanic rocks are wide-spread over eastern China and trace the pattern of intra-platemagmatism remotely separated from the subduction zone.Mainly of intermediate-acidic calk-alkalic compositions, thesemagmatic rocks appear to originate in the crust or near theMoho discontinuity; only a few exceptions manifest as ultra-mafic inclusions originated from the base of the lithosphere,but are not related to subduction or collision. The granitoidsare of either an S-type re-melted middle or lower crust originor of an A-type crust-mantle syntactic origin. The volcanicrocks are bimodal exhibiting both basalt and rhyolite-tra-chyte compositions. In Northeast China where widespreadvolcanic rocks are fault-related, eruption ranges are of theorder of 171−191 Ma (Early and Middle Jurassic), while in

the Daqing Oil Field-Dahingganling area, volcanism waslargely confined to the Late Jurassic-Early Cretaceous (160−120 Ma) suggesting a counter-clockwise westward rotationof the volcanic zone. The granitoid occurrences, some obvi-ously fault-related, also show westward migration and a likelya counter-clockwise rotation. As age increases in the Juras-sic in North China, volcanic eruptions along transpressionalfaults exhibit varying orientations imitating the varying ori-entations of the fold axes. During the Jurassic, the fold axesand the volcanic zones changed trend from ENE to NNEsuggesting a counterclockwise rotation. Also during the Yans-hanian Tectonic Period, a separate (isolated) intermediate-acidic magmatism event occurred along the northern bound-ary fault of the Sino-Korean Plate.

The thickness of lithosphere and the lithospheric mantleis an important factor for the localization of magmatism. Inthe Yanshanian eastern China region, active magmatismwas largely confined to the east of the Dahingganling-Shi-wandashan line, the eastern limit of the continental lithos-phere, along which a high gravity gradient is evident signifyingthe westward continental mantle (60−120 km) and the east-ward oceanic mantle (ca. 40 km thick). The eastward tran-sition is from the continental lithosphere (continental crustand continental mantle) to the transitional lithosphere withcontinental crust underlain by oceanic mantle. Transitionallithosphere is only 70−80 km thick with a temperature ashigh as 1200 °C. In this thinner transitional lithosphere, both thetemperature and geothermal gradient are higher than that ofcontinental lithosphere. When a local tectonic detachmentoccurs within such transitional lithosphere, a magmatic sourcearea should be easily formed. In contrast, the magmaticsource area cannot easily form in the continental lithospheredue to its thickness (more than 100−120 km) and low geo-thermal gradient and temperature even if tectonic detach-ment occurs. The author is of the view that the counter-clock-wise movement of the rotating Jurassic China moved east-ward with its continental crust over thin, hot, oceanic litho-spheric mantle of the eastern China to cause widespreadgranitic magmatism.

The Sichuanian Tectonic Period (135−56 Ma) of this vol-ume covers the Middle Epoch of the Early Cretaceous andthe Paleocene Epoch. It is the time of the Sichuanian move-ment which was first recognized in the west Sichuan Prov-ince to be distinctive from the preceded Yanshanian and thesucceeded Himalayan Periods (Tan XC and Li CY, 1948).The contacts between the Cretaceous and the Paleocene havebeen known to be conformable in most areas of China prov-ing that the Sichuanian tectonism was astride the Jurassicand the Cretaceous forming a single tectonic cycle of alter-nating compression and extension. Moreover, a small angu-lar extensional unconformity occurred mainly at the end ofthe Paleocene. In this tectonic period, red clastic fluvial (-lacus-trine) sedimentation prevailed with some volcanic activityunder a hot, arid continental environment in which gypsum

Book review: The Tectonics of China 89

and halite were deposited.The Sichuanian Tectonic System of the Sichuanian Period

was characterized by intra-(continental) plate deformation;and globally, most of Earth’s tectonic plates appear to havemoved to the north. During the same period the followingwere developed: (1) the Bangongco-Nujiang Collision Zone;(2) the basin and range tectonics in eastern China; (3) theclockwise rotation of the maximum principal compressivestress; and (4) the magma-generating extension with detach-ments in either the crust-mantle contact or at the low-veloc-ity layer of the middle crust. During the Sichuanian Period,eastern China began to emerge with its modern landscapeand many economic hydrocarbon and metallic deposits formedin this time interval.

Sedimentary deposits of this period are mainly red fluvio-lacustine-alluvial fan clastics with some volcanics and gyp-sum and halite under hot-arid land conditions; some marinedeposits occur but only in basins peripheral to the plate. TheJurassic-Cretaceous-Paleocene sedimentation was largelycontinuous (with infrequent sedimentary breaks) with weakdeformation only near fault zones, except in northeast China,Inner Mongolia and northern Xinjiang, where organic-richsediments formed under warm humid climatic conditions.Very little tectonism occurred in NW China. The calculatedtectonic stress field in China during the Sichuanian Periodwas mainly NNE shortening and WNW extension; and thecalculated differential stress value decreases from south-west to northeast, presumably reflecting the rapid northeast-ward convergence of the Indian Plate during the SichuanianPeriod.

Though strong magmatism was active in the SichuanianPeriod, the area of the outcropping magmatic rocks equalsonly ~20% of the outcrop area of the total Yanshanian mag-matic rocks and occupy only 5% of the total outcrop area ofmagmatic rocks in China. Outcrops of the Sichuanian mag-matic rocks are linear or scatteringly intruded in compari-son with the very differently emplaced S-type Yanshaniangranites. In eastern China, the Sichuanian magmatic rocksmainly intruded along four NNE-trending transtensional faultdepressions: the Hengduanshan, the Dahinganling-Taihang-shan and the Tancheng-Lujiang fault zones and the coastal

zone of the southeast China. The A-type alkalic granite witha mialolitic structure indicating shallow level intrusion andhigh volatile gas content was intruded during the middleand late epochs of the Sichuanian Period along the south-east coastal region of China, which extends to the Yeong-nam area of the Korean Peninsula. In eastern China duringthe Cretaceous, the orientation of the maximum principalcompressive stress rotated clockwise from NNE to ENE,which was opposite to the Yanshanian counter-clockwisecrustal rotation. It is suggested that the Sichuanian clock-wise rotation resulted from the continuous northeastwardconversion of the Indian and the Gangdise plates and theirconsequent collision with Eurasia along the Bangongco-Nujiang Belt. This collision compressed the area north ofthe belt in a SW-NE direction; in the beginning of the Cre-taceous, eastern China was compressed in an NNE-SSWdirection, which changed gradually to an ENE-WSW direc-tion in the Late Cretaceous.

The author divided the Cenozoic Era of China into threetectonic periods: the Eocene-Oligocene ‘North Sinian Tec-tonic Period’ (56−23 Ma); the Miocene Early Pleistocene‘Himalayan Tectonic Period’ (23−0.78 Ma); and the MiddlePleistocene-Holocene ‘Neotectonic Period’ (since 0.78 Ma).The following chapters concluding the book are: Chapter12, Characteristics and Mechanisms of Chinese ContinentalTectonics; 13, Tectonics and Thermal Regime in the Chi-nese Continental Lithosphere; 14, Mineralization and Tectonicsin China; and 15, Discussion on the Dynamic Mechanismof Global Tectonics. Appendices and Index occupy p. 385−501 in the last part of this book. All readers interested in thegeology of China are invited to peruse this monumentalvolume.

(November, 2011)Ki-Hong ChangEmeritus Professor (Geology)Kyungpook National UniversityDaegu 702-701,Republic of Korea Email: [email protected]