LUH-ULO

NORTH-SOUTH GEOLOGICAL CROSS SECTION THROUGH LUH-ULO - KEBUMEN

ACCRETIONARY WEDGE

PALEOGENE BACK-ARC

NEOGENE FORE-ARC

ACCRETIONARY WEDGE

PALEOGENE BACK-ARC

NEOGENE FORE-ARC

ACCRETIONARY WEDGE

PALEOGENE BACK-ARC

NEOGENE FORE-ARC

CITANDUY LOWLUH-ULO HIGH

YOGYAKARTA

•

•

•

• •

•

PURWOREJOKEBUMEN

CILACAP

BANYUMAS

N* G.SLAMET

*G.SINDORO

- -

N.KAMBANGAN K.BOLONG - HIGH

040 km

BANJARNEGARA

•WONOSOBO

•

BUMIAYUB E S U K I

L U H - U L O H I G H•

PURWOKERTO

PHYSIOGRAPHIC PROVINCEOF LUK-ULO AREA

CENTRAL JAVA

Geologic field camp

SUNDA PLATE

INDIAN-AUSTRALIANPLATE

3000m

3000m

1000m

A

B

1

2

31. CILETUH2. LUH-ULO3. BAYAT

THREE PLACES IN JAVAWHERE TECTONIC ME’LANGECAN BE OBSERVED

REGIONAL GEOLOGIC ANALYSIS ( TECTONIC )OF LUH-ULO

REGION CENTRAL JAVA

Datacollecting

secondaryprimary

Dataprocessing

started with field observation

TectonicAnalysis

DATA PROCESSING

INTENSELY MICRO-FOLDEDGRAPHYTIC PHYLLITE;MYLONITIZED FOLDED

PHYLLITES

INTENSELY MICRO-FOLDEDGRAPHYTIC PHYLLITE;MYLONITIZED FOLDED

PHYLLITES

PERVASIVELY SHEAREDMATRIX AND LOZONGES SHAPEBLOCKS OF ROCKS CONSISTING

OF PHYLLITE, BASALT, ANDGREYWACKE

GREYWACKE

BASALT

PERVASIVELY SHEAREDMATRIX AND LOZONGES SHAPE

BLOCKS OR “BOUDINE”OF ROCKS CONSISTING

OF PHYLLITE, BASALT, ANDGREYWACKE

THE LOZONGES SHAPEGREYWACKE HAS GIVEN

THE APPEARANCE OF THESO CALLED

FISH STRUCTURE

IS CHARACTERISTICSOF A MELANGE

THE “BOUDINE” ARE CROSSCUTTED BY PAIRED

SHEARED FRACTURES WITHSLICKENSIDED SURFACE

σ1

IS CHARACTERISTICSOF A MELANGE

DEFINITION :

a structurally chaotic, pervasively sheared tectonic “mixture”of sedimentary, igneous and metamorphic rocks. Shear jointsand horizontal slickensided surfaces are commom.

Individual EXOTIC and NATIVE blocks range from hundredOf meters in extent to indefinitely unmapable small size,floating in a fine matrix consists of black or grey clayto which multiple sets of slickensides has given shearedappearance

GIANT “BOUDINE”

THE “BOUDINE” ARE CROSSCUTTED BY PAIRED

SHEARED FRACTURES WITHSLICKENSIDED SURFACE

TYPICAL INDICATINGCOMPRESSIONALDEFORMATION

MEASUREMENTS ON THEATTITUDE OF CLEAVAGE SURFACESOF MATRIX HAD A PREDOMINANTNORTHWESTERLY DIP

CARTOON SHOWING A MODEL OFCONVERGENT PLATE INTERACTION

Late Cretaceous(70 Ma) –Paleocene (55 Ma)subduction zone

HAMILTON 1979

GEOLOGIC SETTING OF LUH-ULO REGIONCOMPRISING BROKEN ROCK FORMATIONS

OF DIFFERENT AGE AND LITHOLOGYREPRESENTING PLATE CONVERGENT

PANORAMIC VIEWTO THE NORTH

LUH-ULO RIVER

GEOLOGIC SETTING OF LUH-ULO REGIONCOMPRISING BROKEN ROCK FORMATIONS

OF DIFFERENT AGE AND LITHOLOGYREPRESENTING PLATE CONVERGENT

LUH-ULO MELANGECOMPLEX

(TECTONIC ME’L.)

TOTOGAN (OLISTOSTROME)FORMATION

(SEDIMENTARY ME’L)

WATURANDA(BRECCIA) FORMATION

(TURBIDITE)

SAWTOOTH MORPHOLOGYINDICATING CONGLOMERATION

OF DIFFERENT LITHOLOGY

PILLOW LAVA(TYPICAL MORB)

RADILARIAN CHERTAND RED LIMESTONE

(TYPICAL DEEP SEA SEDIMENTS)AGE: CENOMANIAN

(BASED ON RADIOLARIA)

MORB

LAPISANBASALT

(“DIKES”)

SERPENTINIZED OPHIOLITE(TYPICAL INTENSELY DEFORMED MANTEL MATERIAL)

OLISTHOSTROMEDEPOSITS

ASSORTMENT OF FRAGMENTALSEDIMENTARY ROCKS UP TO

HUNDRED METERS LONG.

THE LARGER BLOCKS AREPREDOMINANTLY LIMESTONES

AND CONGLOMERATE,FLOAT IN A MATRIX OF GREY

MUDSTONE

JATIBUNGKUS LST(OLISTOLITH)

TECTONIC SETTING AND SEDIMENTATION OF STUDY AREA

1. Late Oligocene - Miocene period ( 20 – 5 Ma ) :During this period, the contemporaneous northward subducting Auastralian plate below Sunda Microplate, shifted from north to south resulting in a East-West trendingmagmatic arc (Fig 1) started from Sumatra in the east to Java and continued eastwardto eastern Indonesia. Luh-Ulo area, most probably develop as an intra arc -

fore arc basin of the system , located on the northern edge of the magmatic arc.

LATE CRETACEOUS –EARLY TERTIARY

LATE TERTIARY

MAGMATIC ARC

MAGMATIC ARC( 35 – 20 Ma )

DEVELOPMENT OFSEDIMENTARY ANDTECTONIC MELANGEIN SUBDUCTION ZONE

SUBDUCTION ZONE AND ME’LANGE FORMATION

MEASUREMENTS ON THEATTITUDE OF CLEAVAGE SURFACESOF MATRIX HAD A PREDOMINANTNORTHERLY DIP

IT IS SUGGESTED THAT THE MELANGEHAS BEEN GENERATED BYTECTONIC PROCESSES RELATEDTO THE NORTHWARD SUBDUCTIONOF THE AUSTRALIAN PLATE

EURASIANPLATE

INDIAN-AUSTRALIANPLATE

PACIFIC PLATE

KSU

MA

ICH

AUSTR.

MAGMATICARC

L.CRETACEOUS-PALEOCENE

SUBDUCTION,CILETUH-MERATU’S

SUTURE

50-45 MA

WJCJ

MY BANYUMAS AREA

PEISTOCENE

M I

O C

E N

E

N E

O G

E N

EP

A L

E O

G E

N

PL

I0-

CE

NEL

ME

L

M

E

L

M

E

L

M

E

OL

IGO

CE

NE

EO

CE

NE

PA

LE

O-

CE

NE

1.8

5

11

15.5

22

37.5

43

49

53.5

65

AGE

KARANGSAMBUNGFM

LITHOLOGYTECTONIC

ENVIRONMENTS

CL.BR;SCALY

SCALY CLAY;W.OLISTH.

LUH-ULO ME’LANGECOMPLEX

(117 my)

Glob.angulataGlob.trilloculin.

ACCRETIONARYWEDGE

SUSPENDEDBASIN

SEISMIC DISCONTINUITY

STRATIGRAPHIC SETTINGBANYUMAS (SUB) BASIN

TOTOGAN FM

EXPLANATION

EO-OLIGOCENE MAGM.ARC

EARLY TERTIARY SUBDUCTION

3000m

3000m

1000mAccretionary Basins

Accretionary Ridge

Back Arc Basins

Fore Arc Basin

L.CRETACEOUS – PALEOCENE SUBDUCT.

SUNDA LAND (PLATE)

INDIAN-AUSTRPLATE

SHIFTING OF SUBDUCTION ZONE DURING CENOZOIC

PENOSOGANFM

-•

•

N* G.SLAMET

0 40 km

YOGYAKARTA

CILACAP

+26 MY

++39 MY21-22 MY 26+

*G.SINDORO

•23-28 MY+

PURWOREJO•

BUMIAYU

•PURWOKERTO

ABANJARNEGARA

•WONOSOBO

•

BANYUMAS

•

•

TUF-MARL FM

KEBUMEN

WATURANDAFM

FORE ARCBASINAL AREA

LATE EOCENE EARLY MIOCENEMAGMATIC ARC

GABON FORM.

FM.WATURANDA

TECTONIC SETTING DURING 35 – 20 MA PERIOD

PERTAMINA – ITB ( 2002 )

LUK-ULOREGION

MY BANYUMAS AREA

PEISTOCENE

M I

O C

E N

E

N E

O G

E N

EP

A L

E O

G E

N

PL

I0-

CE

NEL

ME

L

M

E

L

M

E

L

M

E

OL

IGO

CE

NE

EO

CE

NE

PA

LE

O-

CE

NE

1.8

5

11

15.5

22

37.5

43

49

53.5

65

AGE

KARANGSAMBUNGFM

TOTOGAN FM

GABON FM

WATURANDAFM

LITHOLOGYTECTONIC

ENVIRONMENTS

BR

TF

BRECCIA(AN.BA.COMPON.)TF.BR;

LAPILLI TF.

CL.BR;SCALY

SCALY CLAY;W.OLISTH.

LUH-ULO ME’LANGE

(117 my)

Glob.angulataGlob.trilloculin.

ACCRETIONARYWEDGE

SUSPENDEDBASIN

MAGMATICACTIVITY

BLOCK FAULTING;

INTRA-ARC BASIN

SEISMIC DISCONTINUITY

STRATIGRAPHIC SETTINGBANYUMAS (SUB) BASIN

FLUXOTURBIDITE

PENOSOGANFM

-•

•

N* G.SLAMET

0 40 km

YOGYAKARTA

CILACAP

+26 MY

++39 MY21-22 MY 26+

*G.SINDORO

•23-28 MY+

PURWOREJO•

BUMIAYU

•PURWOKERTO

ABANJARNEGARA

•WONOSOBO

•

BANYUMAS

•

•

TUF-MARL FM

KEBUMEN

WATURANDAFM

FORE ARCBASINAL AREA

LATE EOCENE EARLY MIOCENEMAGMATIC ARC

PENOSOGANFM

EXPLANATION

QUATERNARY MAG.

MIO-PLIOCENE MAGM.ARC

EO-OLIGOCENE MAGM.ARC

MIO-PLIO - QUARTERNARY SUBDUCTION

EARLY TERTIARY SUBDUCTION

3000m

3000m

1000mAccretionary Basins

Accretionary Ridge

Back Arc Basins

Fore Arc Basin

L.CRETACEOUS – PALEOCENE SUBDUCT.

SUNDA LAND (PLATE)

INDIAN-AUSTRPLATE

SHIFTING OF SUBDUCTION ZONE DURING CENOZOIC

PENOSOGANFM

-•

•

N* G.SLAMET

0 40 km

YOGYAKARTA

CILACAP

+26 MY

++39 MY21-22 MY 26+

*G.SINDORO

•23-28 MY+

PURWOREJO•

BUMIAYU

•PURWOKERTO

ABANJARNEGARA

•WONOSOBO

•

BANYUMAS

•

•

TUF-MARL FM

KEBUMEN

WATURANDAFM

FORE ARCBASINAL AREA

PENOSOGANFM

KALIPUCANG FORMATION

MIO-PLIOCENESETTING

M I O - P L I O C E N E - M A G M A T I C ARC

N

S

HALANG FORMATION

S N

OFFSHORE

MAGMATIC ARC

EXPLANATION

QUATERNARY MAG.

MIO-PLIOCENE MAGM.ARC

EO-OLIGOCENE MAGM.ARC

MIO-PLIO - QUARTERNARY SUBDUCTION

EARLY TERTIARY SUBDUCTION

3000m

3000m

1000mAccretionary Basins

Accretionary Ridge

Back Arc Basins

Fore Arc Basin

L.CRETACEOUS – PALEOCENE SUBDUCT.

SUNDA LAND (PLATE)

INDIAN-AUSTRPLATE

SHIFTING OF SUBDUCTION ZONE DURING CENOZOIC

MY BANYUMAS AREA

PEISTOCENE

M I

O C

E N

E

N E

O G

E N

EP

A L

E O

G E

N

PL

I0-

CE

NEL

ME

L

M

E

L

M

E

L

M

E

OL

IGO

CE

NE

EO

CE

NE

PA

LE

O-

CE

NE

1.8

5

11

15.5

22

37.5

43

49

53.5

65

AGE

KARANGSAMBUNGFM

TOTOGAN FM

PENOSOGANFM

GABON FM

WATURANDAFM

HALANG FM.

BRECCIAMB. ALT.: SS.; MRL;TF AND BR.

TURBIDITE;SLUMPING

LITHOLOGYTECTONIC

ENVIRONMENTS

BR

TF

KALIPUCANGFM REEF LST;

LOCALLY CLST.

ALT.CLC.SS;LST-MRL-TF

BRECCIA(AN.BA.COMPON.)

TF.BR;LAPILLI TF.

CL.BR;SCALY

SCALY CLAY;W.OLISTH.

LUH-ULO ME’LANGE

(117 my)

Glob.angulataGlob.trilloculin.

ACCRETIONARYWEDGE

SUSPENDEDBASIN

MAGMATICACTIVITY

BLOCK FAULTING;

INTRA-ARC BASIN

SUBSIDENCE;BACK-ARC BASIN

MAGMATIC ACTIVITY;

REGIONAL UPLIFT

SEISMIC DISCONTINUITY

MY BANYUMAS AREA

PEISTOCENE

M I

O C

E N

E

N E

O G

E N

EP

A L

E O

G E

N

PL

I0-

CE

NEL

ME

L

M

E

L

M

E

L

M

E

OL

IGO

CE

NE

EO

CE

NE

PA

LE

O-

CE

NE

1.8

5

11

15.5

22

37.5

43

49

53.5

65

AGE

KARANGSAMBUNGFM

TOTOGAN FM

PENOSOGANFM

GABON FM

WATURANDAFM

HALANG FM.

BRECCIAMB.

POLYMICTBRECCIATAPAK FM

SS; MRL;AND BR.Mlsc.

ALT.: SS.; MRL;TF AND BR.

TURBIDITE;SLUMPING

LITHOLOGYTECTONIC

ENVIRONMENTS

PENIRONFM

BR

TF

KALIPUCANGFM REEF LST;

LOCALLY CLST.

ALT.CLC.SS;LST-MRL-TF

BRECCIA(AN.BA.COMPON.)

TF.BR;LAPILLI TF.

CL.BR;SCALY

SCALY CLAY;W.OLISTH.

LUH-ULO ME’LANGE

(117 my)

Glob.angulataGlob.trilloculin.

ACCRETIONARYWEDGE

SUSPENDEDBASIN

MAGMATICACTIVITY

BLOCK FAULTING;

INTRA-ARC BASIN

SUBSIDENCE;BACK-ARC BASIN

MAGMATIC ACTIVITY;

REGIONAL UPLIFT

FORE-ARC \INTRA-ARC BASIN

SEISMIC DISCONTINUITY

FOLDING

LOC.KALI MUNCAR SEBORO

( 2003 )