Perspectives on Tahoe, Baikal and Khuvsgul Lakes
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Perspectives on Lake Baikal (Russia), Lake Tahoe (USA), and Lake Khuvsgul (Mongolia). Gantulga Bayasgalan, MSc. Lecturer, School of Geology and Petroleum Engineering Mongolian University of Science and Technology Ulaanbaatar, Mongolia Visiting Desert Research Institute Scientist
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Perspectives on Tahoe, Baikal and Khuvsgul Lakes
- 1. Perspectives on Lakes Tahoe, Baikal and Khuvsgul Gantulga Bayasgalan Desert Research Institute, Tahoe Baikal Institute, Mongolian University of Science and Technology
- 2. Outline • Tahoe Baikal Institute • Summer Environmental Exchange • Alumni Internship Exchange • Comparison of Lake Baikal, Lake Khuvsgul, Lake Tahoe • Lake Tahoe Nearshore Clarity Monitoring
- 3. Tahoe Baikal Institute Established in 1990, the Tahoe- Baikal Institute (TBI) is a partnership between Lake Tahoe in the Sierra Nevada and Lake Baikal in Southern Siberia that organizes watershed management and environmental exchanges to foster cultural understanding and to develop young environmental leaders.
- 4. What is significant? Tahoe is one Lake Tahoe of the ten deepest lakes on the world and among the clearest
- 5. Sister Lakes RUSSIAN FEDERATION Lake Baikal Lake Khuvsgul CHINA
- 6. The goal of TBI’s flagship program, the Summer Environmental Exchange is to help develop community leaders, resource professionals, and environmental stewards around the world by exposing them to watershed issues through a place-based, interdisciplinary sense at both Lake Tahoe and Lake Baikal.
- 7. Summer Environmental Exchange Program • The SEE consists of : • Small-group investigative projects, • Hands-on ecological restoration work • Meetings with experts and policy-makers • Interactive workshops that simulate environmental problem-solving scenarios
- 8. • In this endeavor the Institute develops: • Community leaders, resource professionals, and • Environmental stewards across the intersections of watershed education,
- 9. TBI focuses on: • Protection & restoration • Research, policy • Sustainable economic development • Environmental technology transfer • Cultural understanding
- 10. Alumni Internship Exchange Program U.S, Russian, Mongolian and international alumni will be given the opportunity to revisit Lake Tahoe (or the surrounding region) or the Lake Baikal watershed in Russia or Mongolia and get to work for a month with an organization that fits in with their career development goals The program includes a short orientation and training by the TBI staff, and four weeks of working at a host organization as an intern/researcher as well as various recreational and cultural activities.
- 11. Other Programs • Education • Mongolian Youth Partnerships and Weekend Outreach (STEEC, Wonders of Water Week, Earth Day, • USFS Grants for Outdoor Explore, professional Exchange Great Sierra River (at both Lake Baikal in Clean Up, Tahoe Basin Watershed Education Siberia and in Summit) Mongolia)—topics include environmental • Eurasia Foundation education, interpretive CSPP International services and Grassroots recreational planning Collaboration for Sustainable for protected lands) Community Development
- 12. Comparison of Lake Tahoe, Lake Baikal, Lake Khuvsgul Lake Khuvsgul Lake Baikal Lake Tahoe
- 13. Lake comparison table Lakes Tahoe Baikal Khuvsgul Basin Countries USA Russia/Mongolia Mongolia Average depth /m/ 300 744.5 138 Maximum depth /m/ 502 1642 268 Surface area /km2/ 496.21 31722 2760 Shoreline perimeter /km/ 114 2100 380 Origin Tectonics/block faulting Tectonics/Rift valley Tectonics/Rift valley Max length /km/ 35 636 136 Max width /km/ 19 79 36.5 Salinity/Freshwater Fresh Fresh Fresh Existing place Sierra Nevada Southern Siberia Eastern Sayan Age /years/ 2-4 million 25-30 million 2 million
- 15. Lake comparison table Lakes Tahoe Baikal Khuvsgul Surface Elevation /m/ 1897 455.5 1645 Islands 1 27 4 Water volume /km3/ 150.682 23615.39 480.7 Residence time /years/ 650 330 ?? Settlements South Lake Tahoe Irkutsk Khatgal Catchment area /km2/ 1310 560000 39840 Number of tributaries 63 331 99 Primary inflows Upper Truckee Selenga Arsain River Primary outflows Lower Truckee Angara Egiin River Ocean basin Continental/Pyramid Lake Arctic Arctic Freeze status Never Januay/May January/May Secchi /m/ 24 40 18
- 16. Tectonics and geology of Lake Baikal • Located on the border of the 2 large tectonic structures, Siberian platform and Sayan- Baikalsky folded thrust belt • Tectonically active • Earthquake tremors ~ 2000 annually • Moving towards Pacific 2 mm annually • In a distance of circa 50 years, earthquakes with strengths of over 6.5 on the Richter-scale may happen
- 17. Tectonics and geology of Lake Baikal • The Baikal rift zone is characterized by high surface heat flow, flanking normal faults, and lower upper mantle velocity. • The 1500 km echelon system of rift depressions is the most seismically active continental rift in the world.
- 18. Lake Baikal Geology and fault map • The Baikal rift is more than 2000 km away from the nearest active plate boundary • Siberian Craton and Sayan belt origin in Precambrian and Palaeozoic collisions of terranes and continental blocks. • Archean greenstone crustal cores and granite – gneiss – domes,
- 19. Tectonics and geology of Lake Baikal • Marbles, granulites, amphibolites, shists, gneisses and granitoids. • The island arcs were once in front of the southern shore of the Siberian craton, before it collided with Laurentia and the supercontinent Rhodinia was formed.
- 20. Lake Khuvsgul and Darkhad Depression • Khuvsgul is one of the 25 oldest lakes on the world • Water Clarity stands for one of the best on the world • Contains 0.4 % of the surface freshwater reserve on the world and 70% of Mongolia • Alpine freshwater lake at height of 1645 meters (5400 feet) • Tectonic/Rift valley origin • Calcium carbonate is common in the area along with phosphorus resources
- 21. Sister Lakes Lake Baikal Lake Khuvsgul RUSSIAN FEDERATION CHINA
- 23. What is interesting from Darkhad Depression, Khuvsgul Lake area? • Shorelines confirm that this area was once filled by the lake at a certain time. • Catastrophic floods due to climate change in the end of LGM ~13000 years BP • Moraine deposits on the confluence of rivers in the NW part of the study area • Mollusk and shell remains were abundantly found in this area.
- 24. Darkhad and Khuvsgul climate reconstruction approaches • Although geomorphological evidence can provide useful insights into former climatic regimes and environmental conditions, a more detailed impression of events during the Quaternary can often be gained from sedimentary records. • The sedimentary accumulation is an archive of ancient earth story. It deposits with its important signatures such as climate, environment, and biologic features of particular period. Since it’s a record of old time, sedimentary record can give us enormous information about the past.
- 26. Darkhad Depression Ice dam location?
- 27. GTOPO 30 DEM Map Confluence of the rivers where ice dam was located
- 28. Location of ice dam and estimated filling of the lake using highest shoreline (A. Gillespie et.al 2001)
- 29. Ice dam location on the confluence of the rivers and lateral moraine (A. Gillespie et.al 2001)
- 31. The confluence of the rivers where ice dam was located
- 32. Lake Tahoe geologic origin Processes contribute to Geologic origin of Lake Tahoe: • Marine deposition – meta-sedimentary remnants • Granitic intrusion • Tectonic uplift • Volcanic eruptions • Glacial scouring • Erosion
- 33. What is significant? Tahoe is one Lake Tahoe of the ten deepest lakes on the world and among the clearest
- 34. Lake Tahoe simplified geology map (Adapted from R. Schweickert et. al, 2009)
- 35. Fault map of Lake Tahoe superimposed over DEM and bathymetry map Red: Active faults Black: Age relation unknown Adapted from Schweickert et.al 2004
- 36. Tectonics and geology of Lake Tahoe • The oldest rocks in the area are seen as isolated remnants of metamorphosed Paleozoic and Mesozoic volcanic and sedimentary rocks • The metamorphic remnants are the products of ancient volcanic arcs and related submarine sedimentary deposits
- 37. Tectonics and geology of Lake Tahoe • Prior to the main uplift of the Sierra Nevada ancient Tertiary (Eocene?) rivers passed through the area carving channels • These rivers also provided the channels that carried the volcanic flows and debris from the early volcanic centers
- 38. Tectonics and geology of Lake Tahoe • Volcanism was widespread during the Tertiary. • The early volcanic episode was followed by a period that extended through most of the Miocene and into the Pliocene • Volcanic eruptions continued into the Pleistocene and consisted mainly of basalt and latite flows
- 39. Tectonics and geology of Lake Tahoe • During the Pleistocene, glaciation played a major role in the shaping of the landscape. • Faulting has played a part in the formation of Lake Tahoe. • It is generally accepted that Lake Tahoe was formed by a combination of block faulting and damming of the outlet, at the north end of the basin
- 40. Geologic similarities among Lakes Baikal, Khuvsgul and Tahoe • Having tectonic origin • Exceptionally deep and clear • Alpine Lakes • Glaciation plays an important role • Currently tectonically active • Cut by several major faults • And, keeping their clarity, pristine state is important
- 41. Lake Tahoe Nearshore Monitoring Gantulga Bayasgalan, Angela Stevens, Alan Heyvaert, Charles Morton Brian Fitzgerald, Rick Susfalk, Tim Minor and Ken Taylor Desert Research Institute, Tahoe Baikal Institute, Mongolian University of Science and Technology
- 42. Importance of Monitoring • How to keep these types of lakes clean and clear is a critical management question – they contain significant portions of the total surface freshwater reserve on earth. • Most previous work at Lake Tahoe has been conducted in the mid-lake or pelagic zones. – More recently, work has begun to investigate changes in nearshore conditions.
- 43. Water Clarity • Decline in water clarity due to atmospheric wet/dry deposition, sediment mixtures in runoff, and other anthropogenic impacts • Traditional methods of measurement – Secchi Disk – Turbidimeters – Transmissometers
- 44. Lake Tahoe Water Clarity • Lake Tahoe’s annual average Secchi depth has decreased by about one-third since the 1960s. http://terc.ucdavis.edu
- 45. Data Collection Pump intake on boom. Thermister. Flowmeter Relative Chlorophyll Turbidity Light Transmissivity
- 46. South Lake Incline Village Emerald King’s Bay Beach Mean of means and mean for coefficients of variation for turbidity and transmissivity displayed by 1-km nearshore Nearshore divided into 1-km long sections sections (reaches). Whole-lake means included all nearshore sections, eleven surveys. for spatial analysis of turbidity and transmissivity.
- 47. Turbidity Turbidity measurements from Lake Tahoe nearshore circuits. Data were assembled in 1-km sections to represent the aggregate measurements within each section for that run and the corresponding coefficient of variation for data within each section.
- 48. Transmissivity Transmissivity measurements from Lake Tahoe nearshore circuits. Data were assembled into 1-km sections to represent the aggregate measurements within each section for that run and the corresponding coefficient of variation for data within each section.
- 49. Conclusion • Considering these issues and evaluating the data will be critical to help manage deep, clear-water lakes of the world and our water resources for the future. • Although there is no current standard for light transmissivity in Lake Tahoe, it will be important to establish a monitoring program that would collect the data needed to more fully evaluate existing conditions, its variability, and the relationships to other metrics, like turbidity.
- 50. Thanks very much! • Desert Research Institute • Tahoe Baikal Institute Questions???
Notas del editor
- Established in 1990Lake Tahoe in the Sierra Nevada and Lake Baikal in Southern Siberia.Develops Community Leaders, resource professionals, and environmental stewards…
- Participants will enjoy a unique opportunity to learn about current initiatives in environmental science and policy, as well as the natural and cultural history of the Tahoe and Baikal watersheds, including Mongolia's Selenga River, the largest tributary to Lake Baikal. They will spend 4 weeks at Lake Tahoe, 10 days in Mongolia, and 4 weeks at Lake Baikal, discovering other cultures in a way that cannot be replicated in a classroom.
- Through small-group investigative projects, ecological restoration work, meetings with experts, and interactive workshops that simulate environmental problem-solving scenarios, participants apply their diverse skills and observe how political, legal, and administrative bodies work together with researchers, academic organizations, non-profits, businesses, and residents to promote stewardship and environmental protection.
- U.S, Russian, Mongolian and international alumni will be given the opportunity to revisit Lake Tahoe (or the surrounding region) or the Lake Baikal watershed in Russia or Mongolia and get to work for a month with an organization that fits in with their career development goals to really help to advance their professional development and to be able to benefit both the host and home watershed
- Rift zoneLocated on the border of the 2 large tectonic structuresSiberian platform andSayan-Baikalsky folded thrust beltEurasian and Amur plate divergent boundaryTectonically active Earthquake tremors ~ 2000 annually1862 – 11 magnitude 1959 – 9 magnitude earthquakes Moving towards Pacific 2 mm annuallyIn a distance of circa 50 years, earthquakes with strengths of over 6.5 on the Richter-scale may happen
- The Baikal rift zone is characterized by high surface heat flow, flanking normal faults, and lower upper mantle velocity. The 1500km echelon system of rift depressions is the most seismically active continental rift in the world. During the past 280 years, 13 earthquakes with magnitudes larger than 6.5 have occurred within this area. The Baikal rift is more than 2000 km away from the nearest active plate boundary, and hence it is well suited to study the intracontinental rifting (D. Zhao, 2006)
- Siberian Craton and Sayan belt origin in Precambrian and Palaeozoic collisions of terranes and continental blocks with the Siberian craton. Some relicts of Archean greenstone crustal cores and granite – gneiss – domes, which show a polyfacial and polycyclic metamorphism of granulite and amphibolite facies, but most rocks are metamagmatic and metasedimentary rocks from the lower Proterozoic stage. Around the lake, these are marbles, granulites, amphibolites, shists, gneisses and granitoids. Also within the fold - zone are relicts of oceanic crust and island arcs with ultrabasic rocks and metamorphosed basic magmatics. The island arcs were once in front of the southern shore of the Siberian craton, before it collided with Laurentia and the supercontinent Rhodinia was formed. Rhodinia broke up in the Upper Proterozoic (~700 Ma) at the place where today the rift is (D. Hutchinson, S. Colman 2003).
- The oldest rocks in the area are seen as isolated remnants of metamorphosed Paleozoic and Mesozoic volcanic and sedimentary rocks that were intruded by the Jurassic and Cretaceous granitic rocks of the Sierra Nevada batholith. The metamorphic remnants are the products of ancient volcanic arcs and related submarine sedimentary deposits (Harwood and Fisher, 2002).
- Prior to the main uplift of the Sierra Nevada ancient Tertiary (Eocene?) rivers passed through the area carving channels and depositing accumulations of gravel, sand and silt derived from the erosion of the older metamorphic basement rocks. These rivers also provided the channels that carried the volcanic flows and debris from the early volcanic centers that developed locally and to the east (Harwood and Fisher, 2002; Schweickert and others, 2000a).
- Volcanism was widespread during the Tertiary. The earliest deposits were Oligocene and possibly early Miocene age rhyolitic ash-flow tuffs, that originated from the east (Harwood and Fisher, 2002). This early volcanic episode was followed by a period that extended through most of the Miocene and into the Pliocene, characterized by large accumulations of andesitic mudflow breccia and andesite and basaltic andesite flows. Volcanic eruptions continued into the Pleistocene and consisted mainly of basalt and latite flows that were deposited on the older volcanic sequences (Harwood and Fisher, 2002; Schweickert and others, 2000a).
- During the Pleistocene, glaciation played a major role in the shaping of the landscape. Birkeland (1964) recognized four glacial episodes in the northern part of the basin. He established their relative ages and correlated them in part with other known glacial stages in the Sierra Nevada. Evidence of glacial activity is apparent throughout most of the basin. The most commonly recognized glacial feature are the moraines, the long narrow ridges composed of granitic and volcanic debris scoured from the local rocks. They can be seen around Fallen Leaf Lake, Emerald Bay and Meeks Bay on the west and southwestern shore of the lake.It has generally been known, since the first geologists explored the area, that faulting has played a part in the formation of Lake Tahoe. Studies related to the distribution and types of faults in and around the area have led to a better understanding of how and to what extent faults have played in the development of the basin. It is now recognized that basin-and-range type faulting has extended into the area creating a series of west-tilted blocks bounded by east-dipping faults that produce the north south-trending basin that Lake Tahoe now occupies. It is generally accepted that Lake Tahoe was formed by a combination of block faulting and damming of the outlet, at the north end of the basin, by repeated episodes of volcanic activity and glacial advances
- Introduce preliminary results from nearshore clarity monitoring conducted at Lake Tahoe
- ~15%, 1%
- To determine which areas of the nearshore would best represent current background conditions the data from 1-km section polygons of applicable surveys were averaged to provide a mean of means and the mean for coefficients of variation (CVs) within each section. This approach equally weighted the data from each survey and was not biased by the different number of underlying data points within a given section during a specific survey