Wilsons lecture Fluvial o Different rivers braided meandering Braided rivers

Wilsons lecture fluvial o different rivers braided

This preview shows page 3 - 6 out of 6 pages.

Depositional environments: Dr. Wilson’s lecture Fluvial o Different rivers (braided, meandering…) Braided rivers: River is active across entire valley
Image of page 3

Subscribe to view the full document.

Flood plain not well developed Channels ephemeral, bars and islands highly mobile Muddy deposits less extensive Coarser overall Fewer obvious overbank muds from floodplain Meandering rivers: River is active in isolated section of the valley Flood plain is well developed Channel relatively stable, although point bars can migrate laterally over time Deposits are generally finer overall and are capped with floodplain deposits o Is the Mississippi a braided, or meandering river? Meandering o Cut bank and point bar Cut bank= area of erosion Point bar= area of deposition Walther’s law o Coastal and fluvial examples “only those facies can be superimposed (or stacked immediately on top of one another) which can be observed beside each other at the present time” Aeolian deposits are characterized by? Transgression-Regression (what do they mean/refer to and be able to determine from a stratigraphic column like in the homework) o Transgression= sea level rise, shoreline moves toward higher ground o Regression= sea level lowers, shoreline moves toward shallower ground Relative vs absolute dating o Relative dating= science of determining the relative order of past events without necessarily determining their absolute age o Absolute dating= process of determining an age on a specified chronology Geologic correlation o 3 Different types (lithostratigraphy, biostratigraphy, chronostratigraphy) act of comparing and connecting stratigraphic data sets from outcrop or drill core records on the basis of: biostratigraphy—correlating and assigning relative ages of rock strata by using the fossil assemblages contained within them chronostratigraphy—absolute dating methods using isotope decay Absolute dating: radioactive decay of unstable isotopes What causes subsidence?—what is subsidence? o Subsidence= lowering of a landsurface o Causes: Compaction Dewatering Structural Geology Rule of Vs o Bedding attitude/behavior and topography reflected in how the beds outcrop o Strike= the intersection between a given plane and the horizontal surface o Dip (true dip)= the maximum inclination of a plane; it is measured perpendicular to the strike direction
Image of page 4
o Apparent dip= the inclination of an oblique line on a plane; always less than true dip o Rule of Vs states that where dipping surfaces are incised by a stream/river/valley/canyon, their map view will make a “V” in the direction of dip; and the shape of the V changes depending on the dip angle 3 Types of faults o Reverse fault A fault where the hanging wall moves up relative to the footwall Generally occur in places where the lithosphere is being compressed, hence it is the dominate structure of collision mountain belts o Normal fault A fault where the hanging wall moves down relative to the footwall
Image of page 5

Subscribe to view the full document.

Image of page 6
  • Fall '14
  • YanxiaMa
  • Geology, Dolomite

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern

Ask Expert Tutors You can ask 0 bonus questions You can ask 0 questions (0 expire soon) You can ask 0 questions (will expire )
Answers in as fast as 15 minutes