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Last updated April 4, 2007, REFRESH to see the most updated version of this page

The Evolution of Desert Environments

Development of desert environments in an active tectonic zone

Sede-Boqer Campus and Kibbutz Qetura, March 4-8, 2007

Organizers: Ariel Novoplansky, Yoav Avni and Hanan Ginat

Overview

Language

Where and when

Getting to the Sede-Boqer Campus

Who is it for?

PROGRAM

NEW!! Workshop materials

The workshop will feature lectures and excursions by Prof. Bruce Harrison from the Earth and Environmental Science department New Mexico Tech., Socorro. USA, Dr. Yoav Avni from the Geological Survey of Israel and Dr. Hanan Ginat from the Arava Institute, Israel as well as presentations by other participants.

Overview

The workshop will focus on the evolution of desert environments and the past climatic changes in one of the most tectonically active features on earth: the Arava Rift and its western margins in southern Israel that are part of the renown 7,000 km long Syrian – African fault system.

This unique area comprises a variety of landforms associated with active tectonics such as uplifted ridges, downfaulted blocks and deep closed basins such as the Dead Sea and the Yotveta and Evrona playas. Within this zone, rapid changes in the regional geomorphology have beenidentified. At present, the climate in the region ranges from arid to hyper-arid, with a mean annual precipitation of 90 mm in the Negev Highlands and less than 30 mm in the rift Valley.

Several large fresh-water lakes developed in the region 2 to 1.5 million years B.P., . Rich faunal and floral assemblages are found, in these lake sediments suggesting that the regional climate was much more humid at this time. Along the reconstructed lakeshore of the Zihor lake, rich assemblages of pre-historic tools were found, indicating that early humanoid populations were utilizing the lake by 1.5 million years B.P.

During the last million years the area experienced several cycles of arid to semi-arid climstic fluctuations, which left a large variety of pedogenic features which serve as paleoenvironmental indicators for the climatic changes and tectonic deformation in the region. Most recently, increasing desertification is observed primarily through active natural processes. The variability of desert environment and it evolution serves as a good representative for the entire larger area of the Middle East.

Who is it for?

The workshop is expected to be of interest to researchers and graduate students who are interested in dryland environments from academic institutions in Israel and abroad.

Language

The conference language will be English.

About the lecturers

Prof. Bruce Harrison's worldwide work is focused on environmental reconstruction and tectonic geomorphology based on soil studies.

Dr. Yoav Avni's work is focused on landscape evolution, morphotectonics and desertification of the Middle East.

Dr. Hanan Ginat's work is focused on the reconstruction of paleo-environments, hydrological regime and paleo-climates in southern Israel and the adjacent regions in Jordan.

Where and when

Sunday, March 4, 2007, 11:00 we'll convene at class #2 of the Albert Katz International School for Desert Studies. Please consult the campus map on how to get there.

Program

Day 1: Sede Boker campus

Opening session

Introduction: the geological and geomorphological contexts of desert environments. Example from of the Middle East region and the Dead Sea rift.

Afternoon session:

· An overview on the tectonic geomorphology of extensional and transtensional rift systems with some examples from the Arava valley.

· Landscape evolution of desert environments along a climatic transect.

· Short field excursion to Nahal Zin near Sede Boqer campus.

Main topics: Desert environments of the Negev Highlands.

Evening talk:

· "Paleo-climates in the Levant deduced from speleotems", Anton Vacks, The geological Department of the Hebrew University of Jerusalem and the Geological Survey of Israel.

Overnight: Sede Boqer campus.

Day 2: Sede Boqer campus:

A whole day field excursion: from the Central Negev Highlands to the Arava Rift.

· The Syrian Arc fold belt

· The Main units of the geological section of the Negev

· The main stages of the evolution of structure and landscape in the Negev

· Makhtesh Ramon and its relationship to the Arava Rift

· The Miocene Hazeva Formation in the Karkom Graben

· The southern Arava Rift border fault.

Evening talk:

· "The hydrology of the Arava Valley - a cross border perspective", Herzel Naor, T.H.L. Company.

Overnight: Qetura and Lotan.

Day 3: Arava Institute, Qetura.

Morning lectures:

· Lake formation and paleoclimate reconstruction of the past 2 million y in the margin of the Arava Rift – a methodological study.

· Soils and Paleo-soils as environmental indicators for the development of desert environments.

Field excursion: from the Rift margin to the southern Negev

· Tracing the paleo-drainage basins

· The Pliocene climate and the Pliocene-Pleistocene paleo- environments.

· Early Pleistocene tectonics

· The development of Lake Zehiha

· The early Achelian sites in the southern Negev.

Evening talk:

· "The Southern Negev, the Levantine corridor and the out of Africa", Gonen Sharon, Archeology Department, Hebrew University of Jerusalem.

Overnight: Qetura and Lotan.

Day 4: Arava Institute, Qetura

Morning lecture:

· The importance of soils in tectonic geomorphology and fault scarp stratigraphy for tectonic reconstruction and the evaluation of tectonic hazards along active tectonic zones.

Field excursion: the Southern Arava basins of Yotvata, Evrona and Elat.

· Reconstruction of desert paleo-environments

· Climate and active tectonism during the Pleistocene–Holocene interval.

Evening talk:

· "The development of desert cultures in the Levant”, Steve Rosen, Archeology Department, Ben-Gurion University.

Overnight: Sede Boqer campus.

Day 5: Sede Boqer campus

Morning lecture:

· Glacial and post-glacial environments and desertification processes in the northern margins of the Saharan belt.

Field excursion:

· The loess plains of Sede Zin

· The Ein Avedat travertine

· Desertification monitoring site at Nahal Zipporim

Workshop summary.

Getting to the Sede-Boqer Campus

· Reaching Beer-Sheva from Tel-Aviv is best done by a train. Timetable of trains.

· From Jerusalem you should better take the direct Egged buss. Timetable of busses.

· To Midreshet Ban-Gurion take Metropolin bus #60 from Beer-Sheva. Timetable of busses.

· Please use this map to get to the Albert Katz International School for Desert Studies.

Accommodation, meals etc.

· The workshop will overnight on the first and last nights of the workshop (March 4 and 7) at the Sede-Boqer campus and the nights of March 5 and 6 at Kibbutz Ketura. Please indicate your preferences regarding sleeping arrangements in your registration form.

· At the Sede-Boqer campus (first, second and last days of the workshop), you are welcome to use the services of the restaurant, cafeteria and general store (8:00-19:00) located at the local community center (# 12 on map).

· During the Arava part of the workshop (third and fourth days of the workshop) the meals will be kindly provided by Kibbutz Qetura or purchased by you (lunch on the third day) in Yotvata.

Workshop materials

Presentations:

· Geology of the Negev, Yoav Avni

· Desertification, Yoav Avni

· Ground water in the Arava, Hanan Ginat

· Young geology along the rift, Hanan Ginat

· Geological Controls on Moisture Distribution, Bruce Harrison

· Soils, Bruce Harrison

· Evolution of deserts, Bruce Harrison

Selected literature:

· Amit et al. 2006, casues of hyperaridity in the Negev

· Amit et al. 2007, pedogenetic processes in extremely arid environments