Goals of Today s Lecture

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1 Introduction to Geomorphology Goals of Today s Lecture 1. To introduce you to the course organization. 2. To provide you with an idea of what we will discuss in this class. 3. Review of material you need to know as background to this course Lecture 1 Fall

Geomorphologist Department of Geography B.Sc. University of Guelph M.Sc. University of Southern California Ph.D. University of British Columbia Post-Doc University of California, Berkeley I am a geomorphologist interested in landscape dynamics and landscape material transport processes.

2 Geomorphologist Department of Geography B.Sc. University of Guelph M.Sc. University of Southern California Ph.D. University of British Columbia Post-Doc University of California, Berkeley I am a geomorphologist interested in landscape dynamics and landscape material transport processes. Most of my current research involves sediment transport processes in rivers including sand dune dynamics, gravel transport, and bedrock erosion. We do field work in big rivers, lakes and shallow marine environments. We also do controlled laboratory experiments to test hypotheses about landscape dynamics the River Dynamics Laboratory. I have a continued interest in scientifically-based stream restoration (naturalization of streams impacted by landuse practices). Current work: Incision of Bedrock Canyons When continents collide Classical view: uplift is controlled by mantle convection cells Two colliding continents will force a thickening of the crust and building of a mountain root Incision of bedrock channels will allow buoyant forces to lift the landscape surface Flow Structure in a Bedrock Canyon Lecture 1 Fall

3 Sand Heads Mission Hope Thompson R. Chilcotin R. Quesnel Introduction to Geomorphology Fraser River, BC Bed Elevation (m) McBride Moose L Distance upstream of ocean (Km) Venditti and Church, Venditti et al., Nature, 2014 Flow Structure in a Bedrock Canyon 2009 Observations 50km 1200 khz ADCP GPS GPS 600 khz ADCP Venditti et al., Nature, Flow Structure in a Bedrock Canyon Lecture 1 Fall

Depth (m) Height above bed / depth Shear stress

shear stress in Iron Canyon 0-10 -20-30 -40 A B

200 300 400 500 600 700 800 900 1000 1100

A:100% b) B:80% C:60% D:40% E:20% F:0% 0.

2 0 log-fit 250 c) D log-fit inv. mom. bal.

200 Distance from canyon entrance (m) Venditti

, Nature, 2014 Shear stress will average out

4 Depth (m) Height above bed / depth Shear stress (Pa) Introduction to Geomorphology Impacts on shear stress in Iron Canyon A B C D E F a) Bedrock constrained Distance from the canyon entrance (m) m/s Flow 1 A:100% b) B:80% C:60% D:40% E:20% F:0% m s log-fit 250 c) D log-fit inv. mom. bal C 100 B A E 50 F Distance from canyon entrance (m) Venditti et al., Nature, 2014 Shear stress will average out through a canyon, incision rate will not! 7 Flow Structure in a Bedrock Canyon 2016 Observations Low flow: Sept High flow: June Lecture 1 Fall

5 2016 Observations Results to come. Lecture 1 Fall

6 Current work: Taan Fjord Landslide Port Starboard Panorama View Lecture 1 Fall

7 2015 DigitalGlobe, Inc. Taan Landslide Marine Expedition Lecture 1 Fall

Results to come. Introduction to Geomorphology (GEOG 213) Instructor: Dr. Jeremy G. Venditti Office: 6236 RCB Email: jeremy_venditti@sfu.

8 Results to come. Introduction to Geomorphology (GEOG 213) Instructor: Dr. Jeremy G. Venditti Office: 6236 RCB Office hour: Mon 14:30-15:30 Or by appointment on Mondays Teaching Assistant: Tingan Li TA Office: 6138 RCB Office hour: Tues 12:30-13:30 (Or by appointment) Lecture 1 Fall

The Course Format Lectures: Mon 12:30-14:20 SECB 1012 Labs: Mon 14:30-16:20 RCB 7110 Tues 10:30-12:20 RCB 7110 There is no lab fee The Readings Required Texts Bierman, P.R. and D.R. Montgomery (2014) Key Concepts in Geomorphology, W.

9 The Course Format Lectures: Mon 12:30-14:20 SECB 1012 Labs: Mon 14:30-16:20 RCB 7110 Tues 10:30-12:20 RCB 7110 There is no lab fee The Readings Required Texts Bierman, P.R. and D.R. Montgomery (2014) Key Concepts in Geomorphology, W.H. Freeman and Company Publishers New York, 494p. Available in Bookstore This is a good introductory textbook. It is the 4 th time I have used it. There are 2 copies on reserve in the library. Note there is a whole series of case studies that accompany the book here: Lecture 1 Fall

covered in class The website Readings and lecture materials

10 The Readings Required Scholarly Articles (4): Suggested further readings: Important works that expand on topics covered in class The website Readings and lecture materials can be found at my website: Lecture 1 Fall

11 The Laboratories Labs begin on September There are 6 laboratory exercises/assignments. See Tentative Lecture and Laboratory Exercise Schedule for due dates and return dates. Late labs will be penalized 1 grade per day. You may contact myself or the TA regarding lab exercise content, but the TA is better suited to deal with specific questions. The Resource Office The Geography Department has a Resource Office where you can go outside of lab hours to use airphotos and maps. Location: RCB 6209 / 6210 Hours: 8:30 12:00 and 13:00 16:30 The Resource office staff is not there to provide help with the lab exercises. Please see the TA for that kind of guidance. Lecture 1 Fall

12 The Field Trip There will be a mandatory weekend field trip to complement topics covered in lectures and labs. CACHE CREEK FIELD TRIP (Tentative schedule) We leave SFU (from Security) at 8:30 am on Saturday, October 28, 2016 and return to SFU around 17:30 to 18:30 pm on Sunday, October 29, Students must pay $50 to the Department of Geography to cover the second day of field trip transportation and accommodations. The Grading Laboratory assignments 40% Field trip report 10% Mid-term examination 25% Final examination 25% Important dates 1. MIDTERM: 12:30-14:20, Mon, Oct 30, Field Essay due: 12:30, Mon, Nov 20, FINAL EXAM: 12:00-15:00, Thursday Dec 14, 2017 Lecture 1 Fall

13 The Course Content Geomorphology is the study of Earth s surface and the processes that form it. As such, it is a crucial component of solutions to a wide range of environmental problems and engineering designs. It has even become an important tool for understanding how far-off planets like Mars and Venus have evolved to their current state. This particular course is about Earth s landscape, its present form, and the processes responsible for its large-scale organization. The goal is to provide students with an appreciation of how the landscape around them formed and its continued evolution with particular focus on landscapes of British Columbia, Western North America, and Canada. Our object of interest at the global scale Lecture 1 Fall

14 Our object of interest at the continental scale In this course we will focus on Western NA, Canada, BC Why does earth s surface look like this? Our object of interest at the local scale Lecture 1 Fall

flow April, 2008 The local scale is where the

15 Our object of interest at the local scale Flooding happens at the at local scale Pachena River at base flow April, 2008 The local scale is where the change is most obvious and relevant. Lecture 1 Fall

Flooding happens at the at local scale Pachena River April 28, 2008 @ 2pm

Flooding happens at the at local scale Pachena River April 28, 2008 @ 4pm

16 Flooding happens at the at local scale Pachena River April 28, 2pm The local scale is where the change is most obvious and relevant. Flooding happens at the at local scale Pachena River April 28, 4pm The local scale is where the change is most obvious and relevant. Lecture 1 Fall

17 The local scale is where the change is most obvious and relevant. The local scale is where the change is most obvious and relevant. Lecture 1 Fall

18 Our object of interest at the grain-scale This scale controls what happens at the larger scales! Questions we will answer in this course Lecture 1 Fall

19 1. What is the fundamental basis of geomorphology? 2. What controls topographic relief? Bill Dietrich Bill Dietrich Marin County, CA Himalayas Lecture 1 Fall

20 3. Where do landscape materials come from? Weathering, soil production, and bedrock erosion Bill Dietrich David Montgomery 4. How do landscape materials get down from mountain tops to valley floors? D. Montgomery Lecture 1 Fall

21 5. How do landscape materials get from valley floors to their ultimate sink (oceans or lakes) Lena Delta, Siberia David Montgomery 6. How do glaciers modulate landscape development? Barnard Glacier, Alaska Lecture 1 Fall

22 8. Has the emergence of life on this planet affected the large scale topographic organization of the earth? Why Study Geomorphology? 1. Earth s surface is our home! Lecture 1 Fall

Why Study Geomorphology? 1. Earth s surface is our home!

floods, dust stroms) are significant natural hazards 2.

physical characteristics of earth s surface as its

floods, dust storms) are significant natural hazards

23 Why Study Geomorphology? 1. Earth s surface is our home! 2. All earth s organisms rely on physical characteristics of earth s surface as habitat. 3. Many transport processes (landslides, debris flows, floods, dust stroms) are significant natural hazards Why Study Geomorphology? 1. Earth s surface is our home! 2. All earth s organisms rely (in varying degrees) on physical characteristics of earth s surface as its habitat. 3. Many transport processes (landslides, debris flows, floods, dust storms) are significant natural hazards David Montgomery Lecture 1 Fall

24 Where is this topography? Lecture 1 Fall

25 Distributary Fan: "Smoking Gun" Evidence for Persistent Water Flow and Sediment Deposition on Ancient Mars NASA Press release on 3 November 2003 Lecture 1 Fall

26 The end Review of Geological Concepts or things you should know from GEOG 111 or EASC 101 Reading Assignment: You should review the material on the following slides. If you don t remember some of the material, review you GEOG 111 or EASC 101 textbooks and notes. Lecture 1 Fall

27 Review of Geological Concepts or things you should know from GEOG 111 or EASC 101 Rock Materials: We need to understand the basics of rock materials because they contain information about how they were formed. As such, rock materials allow us to estimate the overall history of a site and the rates of geomorphic processes (weathering rates, transport rates, transport distances). Fortunately, knowledge of a few basic minerals is all that is needed to understand how most landscapes develop. Review of Geological Concepts Rock Types: or things you should know from GEOG 111 or EASC 101 1) Igneous: Form directly from the cooling of magma (e.g. basalt, granite). 2) Sedimentary: layers of this debris get compacted and cemented together (sandstone, mudstone, limestone, Halite). 3) Metamorphic: Rocks whose minerals have become unstable in their environment and are changed into something new (e.g. slate, schist, gneiss, and marble) Lecture 1 Fall

28 From Ritter, 2002 Lecture 1 Fall

29 The portion of the lithosphere that is of greatest interest to us (i.e. the exposed surface) is largely sedimentary rock overlain by loose sediments. From Ritter, 2002 The Rock Cycle Lecture 1 Fall

Intrusive Crystallization temperature Introduction to Geomorphology Bowen s Reaction Series First to Crystallize Last to Crystallize The Classification of Igneous Rocks

30 Intrusive Crystallization temperature Introduction to Geomorphology Bowen s Reaction Series First to Crystallize Last to Crystallize The Classification of Igneous Rocks Phaneritic Aphanitic (Coarse Grained) (Fine Grained) Granite Granodiorite Diorite % Silica Rhyolite Dacite Andesite Extrusive Gabbro Basalt Peridotite Lecture 1 Fall

31 Cementation Introduction to Geomorphology Fissility Compaction The Classification of Sedimentary Rocks Clastic (Detrital) Sediments Arkose (Abundant felspar) Graywacke (Abundant rock fragments, felspar & clay) Shale Breccia (Angular pebbles) Quartz Arenite Mudstone (Common name for > 50% silt & clay) Conglomerate Sandstone Siltstone Claystone Gravel Sand Silt Clay 2 mm mm mm Nonclastic (Chemical) Sedimentary Rocks Inorganic Biochemical Limestone (calcite) Dolomite Halite Gypsum Limestone (calcite) Chert Coal Lecture 1 Fall

Quartzite (sandstone) Hornfels (Many sed.

32 Increasing Metamorphism Introduction to Geomorphology Classification of Metamorphic Rock Foliated Non-Foliated Gneiss (many sed & igneous) Schist (Phyllite) Phyllite (slate) Slate (Shale) Fine Coarse Gneiss Quartzite Quartzite (sandstone) Hornfels (Many sed.) Fine Coarse Particle Size Classification Millimeters (mm) Microns (µm) Boulders 256 Cobbles Gravel (Pebble) 2 64 Sand Silt Clay Lecture 1 Fall

33 Boulders (>256 mm) Cobbles ( mm) Lecture 1 Fall

34 Gravel (2-64mm) Sand ( mm) Lecture 1 Fall

35 Silt (64 2 µm) Clay (<2mm) Lecture 1 Fall

36 Grain-size distributions Percent Retained Probability Distribution Function (PDF) Grain-size (mm) Percent Finer Cumulative Distribution Function (CDF) Grain-size (mm) Lecture 1 Fall

37 Lecture 1 Fall

As compaction and cementation of these sediments eventually occur, which area will become siltstone? A) A B) B C) C D) D

As compaction and cementation of these sediments eventually occur, which area will become siltstone? A) A B) B C) C D) D 1. A student obtains a cup of quartz sand from a beach. A saltwater solution is poured into the sand and allowed to evaporate. The mineral residue from the saltwater solution cements the sand grains together,