Plate Tectonics and Crustal Evolution

This book has grown and evolved from a course I teachat New Mexico Tech, which is taken chiefly by seniorsand graduate students in the Earth Sciences. The rapidaccumulation of data on plate tectonics, mantle evolutionand the origin of continents in the last decade hasnecessitated continued updating of the course. The bookis written for an advanced undergraduate or graduatestudent, and it assumes a basic knowledge of geology,biology, chemistry, and physics that most students in thEarth Sciences acquire during their undergraduate educationIt also may serve as a reference book for variousspecialists in the geological sciences who want to keepabreast of scientific advances in this field. I have attempteto synthesize and digest data from the Helds ooceanography, geophysics, geology, planetology, andgeochemistry, and (o present this information in a systematicmanner, addressing problems related to the evolutionof the Earth's crust and mantle over the last 4 Gy.The role of plate tectonics in the geological past is examinein the light of geologic evidence, and exampleof plate reconstructions arc discussed.Since the third edition was published a wealth of informationon plate tectonics, mantle structure, and continentaorigin and evolution has appeared in scientificjournals. As with the third edition, to accommodate thisnew information, it was necessary to rewrite more thanseventy-five per cent of the text and add a large numberof new figures. Major additions and/or revisions in thefourth edition occur for such topics as mantle plumesseismic discontinuities in the mantle, supercontinents,interactions between Earth systems, atmosphere andocean evolution, episodisity of orogeny and continentalgrowth, and planetary originIn order to better to accommodate new results and ideas,some topics have been eliminated from the third edition(for instance, most of the material on methodology inthe third edition Chapter 1), and many new topics havbeen added. Also, the book has been completely reorganizedand now all planetary topics occur in the laschapter. In Chapter 1 it is assumed that the reader isfamiliar with the basic tenets of plate tectonics and hence,rather than gloss over all topics related to plate tectonicsin a cursory manner, selected topics are discussed indetail. Major topics include plate boundaries, platmotions, hotspots, geomagnetism, Earth systems, andsupercontinents. In Chapter 2, geologiand geophysicalproperties of crustal types are reviewed, heat flowexhumation, cratonization, and crustal composition are discussed in detail, and the concept of crustal provincesand terranes is introduced. Chapter 3 on Tectonic settingsfollows thesame format as the tectonic settingchapter in the third edition. New tectonic settings areadded (giant dyke swarms, submarine plateaux) andcollisional orogens arc discussed in greater depth. Becausethe Precambrian chapter is eliminated in the fourthedition, uncertain tectonic settings found in the Precambria(Archean greenstones, anorogenic granites) arincluded in Chapter 3. Chapter 4, The Earth's mantleand core, has been significantly revised and enlargefrom our rapidly increasing data base from seismic tomography,high pressure experimental data, and computermodelling. New topics aremantle plumes, and geochemical domains in the mantle,and the discussions of mantle convection, seismic discontinuities,and mantle composition are significantlyrevised and updated. The discussion of the core is alsocompletely revised.In Chapter 5 both crustal and mantie evolution arediscussed, with emphasis on the interaction between thetwo systems. New sections include the Earth's oldesrocks, plate tectonics with time,and Archean plate tectonicsIn addition, the sections on episodic age distribution,continental growth rate, and secular changes incomposition of the crust-mantle system have been significantlyrevised in the light of new data and modelsBecause of the wealth of information on the origin aninteraction of the atmosphere, ocean, and living systems,Chapter 6 is almost twice the size of the other chapters.All topics are revised in this chapter and new topicsare added on Phanerozoic atmospheric history, carbon