Dissertation > Excellent graduate degree dissertation topics show

Study on Environmental Change from 200 to 80K a B.P. in Hanyuan Sichuan Province from Lacustrine Deposits Record

Author: MengLi
Tutor: ZhangJianPing
School: Chinese Geology University (Beijing)
Course: Paleontology and stratigraphy
Keywords: Hanyuan areas Particle size analysis Environmental evolution Cause Analysis
CLC: P512.2
Type: Master's thesis
Year: 2009
Downloads: 64
Quote: 2
Read: Download Dissertation

Abstract


Lake fishing village to the big trees the town of Sichuan Hanyuan placed sedimentary section as the research object , through rock stratigraphy , geomorphology , sedimentology method , combined with field recording , will be the profile roughly divided into 8 stages of deposition , three cycles of period large trees placed fish profile sedimentary stratigraphic sequence . The average grain size characteristics derived median diameter for 18.12μm, mostly clay , silt , fine sand interbedded . Layering and sorting , the frequency curve showed the bimodal characteristics , the little thick tail ; the Daihai , Xifeng loess , of Xuancheng river sediment particle size distribution and particle size parameters Comparison found Daihai the lake sediments , loess and river sediments significantly different , distinguish the genetic types of sediments and sedimentary environment , namely the large trees placed the fish profile main semi- deep lake - deep lake lake sediments , some lacustrine lake sediments . Large trees placed fish profiles basic achieve 1cm/100a resolution of stratigraphic and sedimentological studies analyzed by high-precision age . Deposition time of approximately 206.74 ~ 80.55 KaBP, formed during the late Middle Pleistocene to Late Pleistocene interim . The push to establish a large tree swing the fish profile high-resolution chronostratigraphic sequence by interpolation and outside . Large trees placed the fish section in the value of the particle size and magnetic susceptibility were positively correlated with Color L was negatively correlated . High school median particle size and magnetic susceptibility values ??, low L value indicates a the precipitation more warm and humid climate and environment ; low median particle size and magnetic susceptibility values ??, high L value indicates less precipitation warm and dry or cool and dry climate and environment . 200 ~ 80 KaBP Hanyuan paleoclimate eight stage of the process is divided into three periods : ( 1) Countdown to the second interglacial final (206.74 ~ 190.32 ka BP) mainly in warm, arid climate and environment ; ( 2 ) reciprocal second Ice Age (190.32 ~ 133.00 KaBP), mainly to cool and wet climate , sandwiched between a cool dry period ; (3) the last interglacial (133.00 ~ 80.55 ka BP) is warm and humid and warm dry fluctuate significantly climate and environment is mainly dominated by warm and humid climate . The Hanyuan precipitation is mainly controlled by changes in the intensity of solar radiation under the influence of the Indian monsoon . As for the temperature change is consistent with global climate change . But the Hanyuan the environment indicators record with them is not fully synchronized or consistent , reflect regional climate characteristics .

Related Dissertations

  1. Spatial Distribution Characteristics of Community Structure Components in Evergreen Broad-leaved Forest of China,S718.5
  2. On the transition of Sociological Analysis Group Events,C912.6
  3. Analysis on Our Country’s Civil Enforcement Status,D925.1
  4. On the Perfection of the System of Reeducation Through Labor,D926.8
  5. Problems and Solutions in Function-achieving of College Student Financial Assistance Institution,G649.2
  6. Power system capacitor explosion causes of and countermeasures,TM533
  7. The Cause Analysis and Countermeasure of Contemporary University Students’s Responsibility Awareness Defect,G641
  8. Suggestions on the Finance Policy of Adjust the Income Gap in Liaoning,F812.0
  9. Crimes of Village Officials,D924.3
  10. Research on the Student Privacy Protection of College Management,D922.16
  11. Students' ideological and moral quality of investigation and analysis,G711
  12. The Research of the Problems and the Management Countermeasures of Rural General Senior High Schools in Fujian Province,G639.2
  13. The Analysis and Enlightenment of the Sino-US trade friction,F224
  14. The Analysis and Suggestion on the TCSOL of China (2001-2010),H195.3
  15. The Investigation to the History of Qing Dynasty Torture System,D929
  16. The Constuct of Police Image in the New Period,D631.1
  17. Olympics major unforeseen events cause analysis,D523
  18. The Preparation and Research of Silicone Deepening Agent for Fabrics,TS195.2
  19. Research on Wildfire Prevention Measures and Power Grid Operation Optimization,TM732
  20. The Research on Six Sigma Quality Management Applied in Flatness of Cement Concrete Pavement,U416.216
  21. Apply Root Cause Analysis to Prevention Transfusion Extravasation,R472

CLC: > Astronomy,Earth Sciences > Geology > Dynamic geology > External force > Denudation,handling the role of the deposition
© 2012 www.DissertationTopic.Net  Mobile