Pres-Hydrogeological Part of Klaten Project (2014) (Heru Hendrayana) PDF

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Summary

Hydrogeological part of the Klaten project Adrien Selles • Advisors: • Heru Hendrayana (UGM) • Sophie Violette (UPMC) 1 • Olivier Béon (Danone R&D) OBJECTIVES Understand the hydrogeological behavior of the East flank of the Merapi volcano • Identification of the hydrosystem structure • Character...

Description

Hydrogeological part of the Klaten project Adrien Selles

• Advisors: • Heru Hendrayana (UGM) • Sophie Violette (UPMC) • Olivier Béon (Danone R&D)

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OBJECTIVES Understand the hydrogeological behavior of the East flank of the Merapi volcano • Identification of the hydrosystem structure • Characterization of the climate pattern •Characterization of the groundwater flow and identification of potential tracers Method used: A pluridisciplinary study: geology, geomorphology, climatology, hydrology, hydrogeology, geochemistry, geophysics…

Hydrogeology contribution to the Klaten Project

A.Selles

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MERAPI Merapi is an andesitic stratovolcano, located in Central Java, elevation 2968 m. This volcanic area is resulting from the subduction of the Indo-Australian plate under the Eurasian plate. Merapi geological evolution - 400,000 B.P.: Pre-Merapi - 40,000 - 14,000 B.P: Old-Merapi - 14,000 - 2,000 B.P: Middle-Merapi - since 2,000 B.P: New-Merapi New-Merapi stage is characterized by three types of eruptions: -basaltic and andesitic lava flows - pyroclastic flows -magmatic and phreatomagmatic eruptions

5 km AQUA Well

Hydrogeology contribution to the Klaten Project

A.Selles

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Geological context The East flank of Merapi volcano is characterized by:  High heterogeneity of facies in a volcano-sedimentary structure (deposits and material remobilization may produce same kind of deposits)

 4 zones with main facies depending on the distance from the summit  Aquifer layers: Pyroclastic flow, blocs layers, lahar deposits With small lateral extension => paleo-channel (filling paleo-valley structure)  Aquitard layers: Andesitic lava, tephra and ashes, tuffs, cooked paleo-soil Large lateral extension (landscape recovering)

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Objectives of the hydrogeological part To characterize the water cycle and the hydrogeological behaviour of the Merapi Eastern flank at watershed scale.

Input

Merapi System

Output

Springs Rain

River

Shallow wells Deep wells

Hydrogeology contribution to the Klaten Project

A.Selles

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Climatical and hydrological network

AQUA production well

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Rainfall monitoring

Rain gauge in Jemowo

Hydrogeology contribution to the Klaten Project

Weather station Gumuk

A.Selles

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The groundwater system

UPPER PART

SB01

SB02

Inventory: 3 mains discharges zones 30 monitored springs 15 shallow dug wells

Monitoring including: Temperature, EC, pH, Total Alkalinity, flow rate, water level shallow aquifer

Ponctual chemical analysis: Major Ions, δ2H, δ18O, 3H Pesticides, Emerging contaminants

Hydrogeology contribution to the Klaten Project

A.Selles

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Rivers discharge monitoring

Automatic Water Level Recorder on the Soka river

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Dug wells monitoring Collaboration with Bina Swadaya Village Facilitator Water level monitoring of 15 wells (every week)

Hydrochemical monitoring (every 2 weeks)

Hydrogeology contribution to the Klaten Project

A.Selles

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Springs monitoring Hydrochemical monitoring of 30 springs.

Flow rate monitoring. Complete a descriptive springs data base.

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Preliminary conclusion Rain spatial repartition • More important in the South part

NW

SE

• Highest rainfall events in the North Identification of 3 discharge zones: • Low discharge +800 m asl • Medium discharge + 400 m asl • Important discharge + 200 m asl Hydrochemical : Identification of 3 springs groups Multi layered aquifer system

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