交錯層理(英語:cross bedding),也稱為斜層理(英語:cross lamination),是在一層地層內由一系列斜交於層系界面的紋層組成的層理,細層理上部與主層理截交,下部與主層理相切[1]。主層理面是平行與當時的水平面,而傾斜的紋層理代表原始局部的沉積面。這種傾斜不是由於沉積後變形的結果,而是由顆粒沿水底面被水拖引到傾斜地面後沉積形成[2]

例如在河底波紋河邊沙洲風成沙丘淺海三角洲前緣斜坡等沉積環境都能形成交錯層理[3]。交錯層理一般可分為板狀交錯層理及槽狀交錯層理兩種。前者上下層理面是平面,後者層理面為弧形[4],此外還有楔狀交錯層理等共八種層理。根據交錯層理的幾何形狀亦可推測沉積環境及流體方向[5]

參考文獻 編輯

  1. ^ Jordan, Thomas H.; Grotzinger, John P. (2012). The Essential Earth (2nd ed.). New York: W.H. Freeman. ISBN 9781429255240. OCLC 798410008
  2. ^ John Collinson ,(2019) Sedimentary structures. Dunedin Academic Press Ltd, Mar 1, 2019 - Technology & Engineering - 320 pages. ISBN 1780466021, 9781780466026
  3. ^ Ashley, G. (1990) "Classification of Large-Scale Subaqueous Bedforms: A New Look At An Old Problem." Journal of Sedimentary Petrology. 60.1: 160-172
  4. ^ Boggs, S., 2006, Principles of Sedimentology and Stratigraphy (4th ed): Pearson Prentice Hall, Upper Saddle River, NJ
  5. ^ Ashley, G. (1990) "Classification of Large-Scale Subaqueous Bedforms: A New Look At An Old Problem." Journal of Sedimentary Petrology. 60.1: 160-172