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Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

The Future of the Aral Sea and its Ecosystem:

Possible scenarios and outcomes

H.P. Nachtnebel, V. Dukhovny, A. Tuchin, A. Sorokin, Y. Roschenko, U. Uhalin, P.D. Umarov, B. Tashmukhamedov, I.

Mirabdullayev, O. Vasilyev, V. Kvon

Contributing scientists

• SIC ICWC:V. Dukhovny, A. Sorokin, Y. Roschenko, R.

Kadirova

• Center of Intergrated Water Systems Research:A. Tuchin, P.D.

Umarov, U. Uhalin, A. Beloglazov, E. Korshak, E. Temlyanceva

• Institute of Physiology and Biophysics & Institute of Zoology at the Academy of Sciences, UZ

Bek Tashmukhamedov, I. Mirabdullayev

• Institute for Water and Environmental Problems of the Russian Academy of Sciences:O. Vasilyev, V.I. Kvon, V. I. Kuzin, A. N.

Semchukov, V. V. Martyanov

• IWHW-BOKU: H.P. Nachtnebel, Prof.H. Holzmann

(2)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Contributing scientists

• SIC ICWC:V. Dukhovny, A. Sorokin, Y. Roschenko, R.

Kadirova

• Center of Intergrated Water Systems Research:A. Tuchin, P.D.

Umarov, U. Uhalin, A. Beloglazov, E. Korshak, E. Temlyanceva

• Institute of Physiology and Biophysics & Institute of Zoology at the Academy of Sciences, UZ

Bek Tashmukhamedov, I. Mirabdullayev

• Institute for Water and Environmental Problems of the Russian Academy of Sciences:O. Vasilyev, V.I. Kvon, V. I. Kuzin, A. N.

Semchukov, V. V. Martyanov

• IWHW-BOKU: H.P. Nachtnebel, Prof.H. Holzmann

Structure of the presentation

• Objectives and introduction

• Identification of scenarios for the Aral Sea region

• Assessment of scenarios

• Summary and conclusions

(3)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Objectives and introduction

The objective is to identify development strategies in the catchment

- to improve socio-economic development and water use in the region

- to achieve ecological sustainability and bioproductivity in the Aral Sea and the surrounding area

Upper catchment (Kirgistan)

(4)

The lower part of the basin (Uzbekistan)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

The Aral Sea catchment

(5)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

The two tributaries

• Syrdarya (Jaxartes)

– 3019 km – 782 670 km2

• Amurdarya (Oxus)

– 2400 km – 534 739 km2

The two tributaries

• Syrdarya (Jaxartes)

– 3019 km – 782 670 km2

• Amudarya

– 2400 km – 534 739 km2

• Danube

– 2880 km – 795 000 km2

(6)

Water sources and consumers

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Some figures about water consumption in Central Asia

• Water sources

– 43% of the annual discharge in the basin originates in Tajikistan

– 24% in Kyrgyzstan

– approximately 19% in Afghanistan.

• water usage

(7)

Physical structure of WM

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Hydrology: Inflow pattern

(8)

Changes of the Aral Sea

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Bathymetry of the Aral Sea

• Sea level until 1960 was about 53 m a.s.l.

• Surface was 69,8 10

3

km

2

• maximum depth was 69 m

• water volume was about 1056 km

3

• about 1100 islands totaling

54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29.75 29.5 29.25 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14

Fig. 4.1. Sink of the Aral Sea

Eastern part Western part

Northern part

(9)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Quantitative changes in the system

Year Sea level Surface Volume (m.a.s.l.) 10

3

km

2

km

3

1960 53,40 69,79 1056,12

1984 42,75 44,92 487,66

1986 41,02 38,56 380,63

2000 33,50 22,93 139,53

Development of water utilisation

(10)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Species composition (total number) in the Aral Sea

Taxa 1971 1981 1989 1994 2000 2001

zooplankton 43 18 13 9 8 5

zoobenthos 82 51 14 7 5

Fish 20 30 17 5 3 2

Salinity (g/l) 12 18 30 37 60 65

Some figures about salinity

• Salinity of regular sea waters 3,5 % 35g/l

• Brakish waters < 1% <10g/l

• Caspian Sea 1,3 % 13g/l

• Mono lake (Nevada) 7,3 % 73g/l

• Dead Sea ~30% 300g/l

(11)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Fish fauna

• Fish fauna in Aral Sea was relatively poor (20 species)

• Caspian Sea had 130 species

• Between 1950-1960 the # rose up to 30 species (introduction)

• With increase of salinity other species were introduced

• 1990 only 5 species were found

• 2001 only 2 species were found (atherine and flounder)

Fauna

• Atherina Flounder

• Artemia

(from Wikipedia)

(12)

Main problems

• intensive cotton monoculture

• extreme environmental degradation

• Intensive pesticide use and salinization

• industrial pollution

• Irrigation lead to a decrease of surface and groundwater

• high rates of disease (cancer) and infant mortality.

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Summary of changes

• Due to a dramatic drop in the influx of water into the Aral Sea, its area has been reduced to 25 %, the volume is now about 10%, the level dropped by 23 m

(13)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Summary of changes

• Due to a dramatic drop in the influx of water into the Aral Sea, its area has been reduced to 25 %, the volume is now about 10%, the level dropped by 23 m

• The Aral Sea has split into two water bodies, the Small Aral (North) and the Large Aral (South). As a result, the water salinity in the Large Aral has grown by a factor of 7 reaching over 80 ppt in the Western basin and 100 ppt in the Eastern basin.

Summary of changes

• Due to a dramatic drop in the influx of water into the Aral Sea, its area has been reduced to 25 %, the volume is now about 10%, the level dropped by 23 m

• The Aral Sea has split into two water bodies, the Small Aral and the Large Aral. As a result, the water salinity in the Large Aral has grown by a factor of 7 reaching over 80 ppt in the Western basin and 100 ppt in the eastern basin.

• The Large Aral has turned into a polyhaline lake. As a result, this has brought about cardinal changes in the composition of the Aral biota. Most of the species disappeared.

(14)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Summary of changes

• Due to a dramatic drop in the influx of water into the Aral Sea, its area has been reduced to 25 %, the volume is now about 10%, the level dropped by 23 m

• The Aral Sea has split into two water bodies, the Small Aral and the Large Aral. As a result, the water salinity in the Large Aral has grown by a factor of 7 reaching over 80 ppt in the Western basin and 100 ppt in the eastern basin.

• The Large Aral has turned into a polyhaline lake. As a result, this has brought about cardinal changes in the composition of the Aral biota. Most of the species disappeared

• The bio-productivity has extremely decreased

A dry region ?

• Yes and no !

(15)

Water Scarcity

• Indicators: Water Scarcity

– less than 1 700 m³ per year per person is available, people experience water stress.

– Less than 1 000 m³ per capita is classified as chronic water scarcity and

– less than 500 m³ as absolute water scarcity

• Rural Water Livelihoods Index (RWLI by FAO in 2009) It includes

– services component (access to water and sanitation), – security component (crop and livestock water), – environment component (clean and healthy water), – entitlement component (secure and equitable water).

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Water Scarcity

UNDP's 2006 Human Development Report

– The scarcity at the heart of the global water crisis is rooted in power, poverty and equality, not in physical availability.

– In many countries scarcity is the product of public policies that have encouraged overuse of water through subsidies and underpricing.

– There is more than enough water in the world for domestic purposes, agriculture and industry.

– The problem is that some people-notably the poor-are systematically excluded from access

– In short, scarcity is manufactured through political processes and institutions

(16)

Water availability (global)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Water Scarcity

(17)

What was done, what could be done ?

• Measures to improve the conditions of the lake

– Institutional set up

– Improving water governance (transboundary management) – Engineering measures

– Water management (improving water use efficiency)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Water management structure in the Soviet period

• early 1980-: average efficiency of irrigation systems (ratio of water used productively at the fields to headworks withdrawals) was around 60% in the Aral Sea basin, the lowest of any region in the Soviet Union

• In January 1988, a state committee for the protection of nature was formed, elevated as the Ministry for Natural Resources and Environmental Protection in 1990.

• The Ministry had authority over all aspects of the environment and the use of natural resources.

• Shortly after, the Interstate Coordination Water Commission (ICWC) was formed by the newly independent states to provide

(18)

Dublin Principles of 1992

• Fresh water is a finite and vulnerable resource, essential to sustain life, development and the environment;

• Water development and management should be based on a participatory approach, involving users, planners and policymakers at all levels;

• Women play a central part in the provision, management and safeguarding of water;

• Water has an economic value in all its competing uses and should be recognised as an economic good

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Transboundary Management

• In February 1992, agreement to coordinate policies on their transboundary waters. Subsequent agreements in the 1990s and in 2002 have updated water management institutions

• 1992: an agreement to coordinate efforts to "solve the Aral Sea crisis"

– carrying out joint research – exchanging information

– adhering to agreed-to regulations for water use and

(19)

long term "Concept" and a short-term

"Program" for the Aral Sea

• 1994: Concept is based on a strict policy of water conservation. Allocation of water for preservation of the Aral Sea was recognized as a legitimate water use for the first time.

• four major objectives:

– to stabilize the environment of the Aral Sea;

– to rehabilitate the disaster zone around the Sea;

– to improve the management of international waters of the basin; and

– to build the capacity of regional institutions to plan and implement these programs.

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Funding

• These regional activities are supported and supplemented by a variety of governmental and non-governmental agencies, including the European Union, the World Bank, UNEP, and UNDP.

• 1995: Nukus Declaration indicated the need for a "unified multi- sectoral approach and the development of cooperation amongst the states and with the international community"

• 2002: Creation of the Central Asian Cooperation Organization (CACO) with a broad mandate to promote cooperation among member states on water, energy, and the environment.

(20)

Lessons learned

• National objectives dominate basin wide interests.

• Lack of trust and credibility among the countries can hinder the process of cooperation.

• Water and energy resources are unequally distributed

• An inefficient water use

• Although a interstate committee has been established none of the plans was implemented

• The Central Asian Economic Community, now the Central Asian Cooperation Organization, playes a key role in mediating between the Aral Sea Basin states when there were difficulties within the International Fund for the Aral Sea.

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Measures in the South Aral Sea and Priaralia region

f(t)

RS f(t) f(t) SA

w SA

e SA m f(t)

(21)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

The priaralie region: Amudarya Delta

d

d d

d d d

d

d

d d

d d

d

$

d d

%

KKS SA-1

MA-1 RA-1 DU-1

KS-1 KS-3

DP-1 PP-1 DP-2

ÊÑ-4 AP-3

AP-1 AP-4

AP-5 AP-2

52.0

58.0 53.0

52.5 52.5 46.0

48.0 43.5

45.0

47.0

7 m3/s

36 m3/s 43 m3/s

24 m3/s

34 m3/s 10 m3/s 20 m3/s 44 m3/s

35 m3/s

39 m3/s

74 m3/s 38 m3/s

40 m3/s 93 m3/s

66 m3/s 36 m3/s

16 m3/s 25 m3/s 70 m3/s

10 m3/s

23 m3/s

44 m3/s 250 m3/s

140 m3/s

52.5 m3/s

1841 m3/s 1225 m3/s

1328 m3/s

1964 m3/s 1348 m3/s

1451 m3/s 2091 m3/s

1475 m3/s 1578 m3/s

Urdabai

Glavmyaso

Kazakhdarya

Mashan-Karazhar

Inzhen erozek

Collector Us

tyurt

Akkai

Ilenkul

Dumalak

Mashankol

Djiltyrbas res.

Muynak res.

Sudochye Mejdurechenskoye

Rybachie

Akdarya

Kung rad-M

uinak Amu-Darya

Qopt = 2458 m3/ c Qint = 1842 m3/ c Qbus = 1945 m3/ c Water discharge in Samanbay

gauging station

Rivers Canals Collectors

Dams dOutlets Hidrounints

$

%Escape

Design:

52.5 ...Water surface elevations

Legend Water flows in scenarios

Optimistic Intermedium Business of usual Saline water Mixed waters

Optimistic Intermedium Business of usual Optimistic

Intermedium Business of usual Fresh water

Aral Sea Variant II I .

Corrected calculation by "Aral Consult"

Schematic map of water flow allocation in the years of maximum water supply

Measures to preserve the Aral Sea

The Northern part

In order to secure the existence of the Northern Aral Sea, Kazakhstan constructed, with a loan and

expertise from the World Bank, the

13-km Kok-Aral dike, which was

completed in 2005 and prevented

the water of the Syr Darya from

flowing into the Southern Aral,

(22)

Planned Measures

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Eastern part:

To preserve the Eastern part

(small surface and large volume) a diversion from the Amudarya was planned in 2000

Observed Improvements

• In addition to the dam

– old infrastructure on the Syr Darya was rehabilitated, – irrigation systems were improved

– several new hydraulic structures were constructed to reduce water losses and increase the flow of the Syr Darya.

– The surface of the Northern Aral Sea grew by 18% and the

(23)

Observed biological improvements

• Biomass (weight of all the fish in the northern sea) was estimated in 2011 to have risen from 3 500 tonnes, most of it a flounder introduced from the Black Sea, to 18 000 tonnes, most of it native, edible species like carp, pike perch, catfish and pike.

• Commercial fishing now accounts for 4 500 tonnes and a fish-processing plant has started operating in Aralsk, exporting the most valuable fish to Russia and other neighbouring countries.

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Water Management:

• Business as usual

• National visions

• Optimistic scenario

• Scenarios from 2006-2025

(24)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Scenarios from 2006-2025

• Business as usual

• National visions

• Optimistic scenario

also considering climatic variability (dry and wet) also considering different water distribution systems in the Deltas

Business as Usual

It is assumed that:

• The region will develop as usual regarding transboundary water management, each country is tending to self-provision in food production.

• Integration processes in transboundary water resources management will be developed slowly.

• Regional integration in agricultural production progresses poorly.

(25)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Toktogul Reservoir

• Construction period: 1962 – 1975

• Water surface of the reservoir: 284,3 km²

• Storage capacity: 19.500 Mio. m³

• Installed capacity: 1200 MW

Toktogul Reservoir

• Construction period: 1962 – 1975

• Water surface of the reservoir: 284,3 km²

• Storage capacity: 19.500 Mio. m³

• Installed capacity: 1200 MW

(26)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Changes in reservoir management

Toktogul Reservoir (Kirgistan)

Was planned for irrigation + hydropower

is recently mainly used for power generation

National Future Development Strategies

• The national development plans of Kazakhstan, Kyrgyzstan, Tadjikistan, Usbekistan, Turkmenistan are analysed

• Indicators are growth rates of population, economic

development, resources use (land, water, energy..)

and social indicators (health, expected life time…)

(27)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Optimistic scenario (close co-operation)

Regional integrated development is supported by all the states:

• mutual beneficial use of transboundary water resources on the basis of water conservation and common environmental approaches

• mutual beneficial agricultural development with focus on regional specialization in agricultural production

• Efficient water and resources use

• economic growth, mainly through industrial and services development

Analysis of the consequences

• Modelling and simulation tools hydrological model

water balance model

water management models agricultural models

economic model

ecological model (salinity, variability, depth)

• Impacts on the water bodies of Aral Sea

• Impacts on the Delta areas

(28)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

An intensively managed catchment

Flow paths and consumers in the Amudarya catchment

Structure of the socio-economic model

(29)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Calibration of the models

Simulation results Salinity in the Eastern lake

54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29.75 29.5 29.25 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 -1 -2 -3 -4 -5 -6 -7 -8 -9 -10 -11 -12 -13 -14 -15 -16

Fig. 4.1. Sink of the Aral Sea

Eastern pa

(30)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Simulation results

Salinity in the Western lake

Seawater salinity

50,00 55,00 60,00 65,00 70,00 75,00 80,00 85,00 90,00 95,00 100,00

2000 2005 2010 2015 2020 2025

g/l

NAT_H SAV_H OPT_H NAT_L SAV_L OPT_L

54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29.75 29.5 29.25 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 -1 -2 -3 -4 -5 -6 -7 -8 -9 -10 -11 -12 -13 -14 -15 -16

Fig. 4.1. Sink of the Aral Sea

Western part

Diversion of the input

Amudarya inflow goes to the Western lake

54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29.75 29.5 29.25 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 -1 -2 -3 -4 -5 -6 -7 -8 -9 -10 -11 -12 -13 -14 -15 -16

Fig. 4.1. Sink of the Aral Sea

Western part

(31)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Impacts on biology

Data collection 2002

Halotolerance of aquatic animals

(32)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Analysis of scenarios

• In all scenarios the Large Sea will separate into a Western and an Eastern lake

• The Eastern lake is very shallow, dries out from time to time and will have an extremely high salt

concentration

• The Western lake is deep, has a large volume and a small surface

• The salt concentration in the Western Sea will be lower than in the Eastern Sea

Analysis of scenarios

• The recent inflow from Amudarya feeds the Eastern part

• The runoff should be diverted to the Western part

• A compensation discharge should remain for the Amudarya Delta and the Priaralia shallow water bodies

• The biology and bioproductivity might be maintained

(33)

What could/should be done?

• A basin wide water management perspective is still missing although an Aral Sea vision has been developed (supported by UNESCO)

• All riperian states have disadvantages from recent water management practice

• The water use efficiency can be substantially improved at all levels

– international by sharing waters in time and space,

– at the national level by improving management practice and by implementing updated technologies (treatment schemes, irrigation practice,…)

– Local level by training and education

• Water scarcity is not the major issue (according to international guidelines)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

New plans and projects in the catchment

Kambarata-1 Project is in the final planning phase a large storage scheme on the Upper Naryn (Kirgistan)

• It will have substantial consequences for the hydrological pattern downstream.

• Further, six other schemes are planned

(34)

New plans and projects in the catchment

Kambarata-1 Project is in the final planning phase a large storage scheme on the Upper Naryn (Kirgistan)

• It will have substantial consequences for the hydrological pattern downstream.

• Further, six other schemes are planned

• It will be the highest dam in the world (~ 275 m)

• The capacity will be about 2,000 MW

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Which water management options could help ?

– Improved institutional cooperation among the riparian states

– Development of a joint water management strategy (transboundary management)

– engineering measures at the local level

– Improved water use efficiency by considering all costs and impacts and by updated techniques

(35)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Summary and conclusions

• The historic development of the Aral Sea region was described for the last 50 years

Summary and conclusions

• The historic development of the Aral Sea region was described for the last 50 years

• Problems are due inefficient water use and a lack of transboundary water management

(36)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Summary and conclusions

• The historic development of the Aral Sea region was described for the last 50 years

• Problems are due to water scarcity, inefficient water use and a lack of transboundary water management

• Based on complex models three scenarios were analysed

Summary and conclusions

• The historic development of the Aral Sea region was described for the last 50 years

• Problems are due to water scarcity, inefficient water use and a lack of transboundary water management

• Based on complex models three scenarios were analysed

• None is able to restore the Aral Sea

(37)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Summary and conclusions

• The historic development of the Aral Sea region was described for the last 50 years

• Problems are due to water scarcity, inefficient water use and a lack of transboundary water management

• Based on complex models three scenarios were analysed

• None is able to restore the Aral Sea

• The major part of the lake is going to dry out soon

Summary and conclusions

• The historic development of the Aral Sea region was described for the last 50 years

• Problems are due to water scarcity, inefficient water use and a lack of transboundary water management

• Based on complex models three scenarios were analysed

• None is able to restore the Aral Sea

• The major part of the lake is going to dry out soon

• The small Western part might be maintained

(38)

Future of Aral Sea and its Ecosystem H.P. Nachtnebel et al.

Summary and conclusions

• The historic development of the Aral Sea region was described for the last 50 years

• Problems are due to water scarcity, inefficient water use and a lack of transboundary water management

• Based on complex models three scenarios were analysed

• None is able to restore the Aral Sea

• The major part of the lake is going to dry out soon

• The small Western part might be maintained

• Parts of the biota may be preserved in the Delta regions

• In the long term the Western part might provide sufficiently low salinity for Artemia

Thank you for your attention

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