Structural and Stratigraphic Interpretation of the Region Around the McArthur Basin ... · 2016. 8....
71
Structural and Stratigraphic Interpretation of the Region Around the McArthur Basin, Northern Territory Prepared For: Final Report May 2011
Transcript of Structural and Stratigraphic Interpretation of the Region Around the McArthur Basin ... · 2016. 8....
-
Structural and Stratigraphic Interpretationof the Region Around the
McArthur Basin,Northern Territory
Prepared For:
Final Report
May 2011
-
Structural and Stratigraphic Interpretation of the Region Around the
McArthur Basin, Northern Territory
Final report
Prepared for:
by
May 2011
15 Garden St. Greenslopes, Qld. 4120 pH: 07 - 3342 0725 Email [email protected]
-
i
S o l i dG e o l o g y
Table of Contents
TABLE OF CONTENTS ..............................................................................................I
LIST OF FIGURES .....................................................................................................II
LIST OF ENCLOSURES .......................................................................................... IV
1 Introduction............................................................................................................................................1 Data Sources ...........................................................................................................................................1 Aims and Objectives................................................................................................................................2
2 Background.............................................................................................................................................3 Rawlings et. al 2004 - Seismic Interpretation ................................................................................3 McArthur Basin Development - Duffett et.al. .................................................................................4 McGoldrick et. al 2010...................................................................................................................4
3 Interpretation.........................................................................................................................................6 The Stratigraphic Sequence.....................................................................................................................7 Interpretation Methodology ...................................................................................................................10 Mapinfo Interpretation Tables ...............................................................................................................13 Features of the Interpretation.................................................................................................................14
Notes on Sequences and Stratigraphic Units .....................................................................................15 Basement .....................................................................................................................................16 Tawallah Group ...........................................................................................................................16 The McArthur Group ...................................................................................................................19 Post McArthur Group - Pre Nathan Group Deformation ...............................................................26 Nathan and Roper Group Deposition ............................................................................................27 Post Roper Group - Pre Cambrian Deformation ............................................................................29
4 Target Selection and Conclusions........................................................................................................29
REFERENCES..........................................................................................................32
-
ii
S o l i dG e o l o g y
List of Figures
Figure 1 - Location of Batten Trough Study Area
Figure 2 - Coverage of Google Earth Image Tiles
Figure 3 - Geoscience Australia seismic line and interpretation
Figure 4 - McArthur Basin stratigraphic column from Duffett et.al.
Figure 5 - Prospect and sub-basin locations around the HYC deposit
Figure 6 - McGoldrick (2010) facies mapping around the margins of the Abner Range
Figure 7 - Location of AEM anomaly at HYC
Figure 8 - Structure of ColourMap table (graphic definition fields not shown)
Figure 9 - Structure of interpreted geology fill polygon table
Figure 10 - Solid Geology Interpretation
Figure 10b - Interpretation legend
Figure 11 - Interpreted major faults and deposits
Figure 12 - Distribution of Tawallah Group
Figure 13 - Distribution of McArthur Group
Figure 14 - Distribution of Gun Super Sequence
Figure 15 - Distribution of Loretta Super Sequence
Figure 16 - Distribution of River Super Sequence
Figure 17 - McGoldrick (2010) River sequence definitions
Figure 18 - Distribution of Emmerugga Sequence
Figure 19 - Distribution of Barney Creek Sequence
Figure 20 - Distribution of Lynott Sequence
Figure 21 - Distribution of Term Super Sequence
Figure 22 - Structural model for deformation event post McArthur Group - Pre Nathan Group deposition
Figure 23 - Syn Nathan Group and Roper Group deposition features
Figure 24 - Structural model for the Post Roper Group deformation
-
iii
S o l i dG e o l o g y
Figure 25 - Bouger Gravity image
Figure 26 - Interpreted structural block boundaries with mineral occurrences and deposits
Figure 27 - Distribution of recessive lithologies and target areas
Figure 28 - Distribution of units with shale as primary lithology
Figure 29 - Distribution of lithologies with evidence for evaporites - target areas superimposed
Figure 30 - All interpreted faults with deposits and target areas
Figure 31 - Summary of internal dips of structural blocks
Figure 32 - Target descriptions
-
iv
S o l i dG e o l o g y
List of Enclosures
Enclosure 1 Time-Space Plot for NW Queensland and northern Northern Territory
Enclosure 2 McArthur River Region, Northern Territory, Solid Geology Interpretation (Scale 1:250,000)
Enclosure 3 McArthur River Region, Northern Territory, Google Earth Image Tiles
Enclosure 4 McArthur River Region, Northern Territory, Image Data Sets
Enclosure 5 DVD containing:
Direct opening Mapinfo workspaces and tables for the project.
Report text in Word format
Report and Diagrams as PDF document
-
1
S o l i dG e o l o g y
1 Introduction
At the request of Larry Stewart of MMG Ltd. a structural / stratigraphic interpretation of the region around the McArthur Basin, Northern Territory (Figure 1) was undertaken by the author (Dr. Stephen King). The main aim of the interpretation was to produce a solid geology map, interpreting the Proterozoic geology under cover where possible.
Data Sources
The main data sources utilised during the map interpretation were:
• 1:250,000 scale geology polygons and polylines in Mapinfo format. The polygon shapes also include the geology depicted in the 1:100,000 Abner Range and McArthur River Region sheets. However, the interpreted faults shown on those sheets are not included in the 1:250,000 Mapinfo dataset. Data was available for the following sheets (see Figure 1):
o Mount Young
o Bauhinia Downs
o Walhallow
o Robinson River
Other digital data that accompanied these sheets included:
o Structural measurements - not always in the same format.
o Mineral occurrence data
o Stratigraphic drill hole locations
o bedding trends
o fold axes
• A raster scan of the 1:250,000 scale Calvert Hills Sheet.
• Raster scans, registered in Mapinfo, of the 1:100,000 Abner Range and McArthur River Region sheets (see Figure 1 for location). These represent the only 1:00,000 scale mapping in the area.
• 1:1.000,000 geology polygons for the Northern Territory.
• Regional ternary radiometrics image (U=blue, Th=green, K=Red) gridded to 100m cell size (McArthur_100m_RAD_KThU_RGB_Unf.tab) - other radiometrics data sets were available but this proved to be the most useful.
• Aeromagnetic images and grids including:
-
Scale 1 : 400,000
Figure No.1 Location of Batten Trough Study Area
LARRIMAH
DALY WATERS
NEWCASTLE WATERS BEETALOO
MOUNT YOUNG
BAUHINIA DOWNS
ALLIGATOR RIVER
MO
WES
ARNHEM BAY
KATHERINE
TRUANT ISLAND
GOVE
PORT LANGDON
CAPE BEATRICE
HODGSON DOWNS
COBOURG PENINSULA
MILINGIMBI
MOUNT EVELYN MOUNT MARUMBA
PELLEW
JUNCTION BAY
BLUE MUD BAY
CALVERT HILLS
ROBINSON RIVER
ROPER RIVER
TANUMBIRINI
URAPUNGA
WALHALLOW
WESSEL ISLANDS
Century
HYCLocation of study area (dark red polygon) withinthe Batten Fault Zone of the NorthernTerritory.Coverage of airborne EM imagery (blue polygon).1:250,000 Sheet Boundaries and names (grey boxes)1:100,000 geology sheets (pink)
McArthur River Region100k Geology
Abner Ranger100k Geology
-
2
S o l i dG e o l o g y
o McArthurBasin_MagRTP_tilt
o Batten_Trough_TMI
o Batten_Trough_VD (Grey Scale)
• Landsat TM imagery, bands 2,4,7 as RGB image. Downloaded from NASA Zulu web site to cover the region. Pixel size 15m.
• Airborne EM images (see Figure 1 for coverage) produced by Rob Angus of RAMA Geoscience including:
o McArthurBain_AEMMerge_EarlyCh - an image of the early channel response highlighting features nearer surface. A grid of this image was also supplied allowing local stretching where required.
o McArthurBain_AEMMerge_MidChan - a mid channel image. A grid of this image was also supplied allowing local stretching where required.
o McArthurBain_AEMMerge_LateCha - an image highlighting responses from deeper levels
o McArthurBain_AEMMerge_Tau - decay constant image.
Coverage of the EM data is not complete.
• Regional Bouger gravity images
• Google Earth images. As no digital aerial photograph or high resolution satellite imagery base could be supplied on which to compile the interpretation a series of image tiles have been downloaded from Google Earth and registered in Mapinfo. A total of 63 tiles have been downloaded and registered using the standard version of Google Earth (Figure 2) - each tile (1894 x 1090 pixels) covers an area of approximately 29km E-W by 17km N-S and have been captured to ensure overlap of the images. If required, higher resolution (4800 pixels E-W) tiles can be downloaded using Google Earth Professional.
• Previous work in the area, referred to during the study included:
o Interpretation of a seismic line across the Batten Trough (see Figure 2 & 3) by Rawlings et. al. (2004).
o NTGS review paper on the McArthur Basin (Ahmad et. al.)
o McGoldrick (2010)
The interpretation has been compiled in Australian Map Grid Zone 53 (GDA94). Google earth images have been captured in Lat/Long WGS84 Zone 53 South which is the equivalent projection.
Aims and Objectives
The main aims and objectives of this study are to:
• create a solid geology map for the study area which interprets units under thin surficial and Cretaceous/Tertiary cover
-
Figure No.2 Coverage of Google Earth Image tiles
650,
000
mE
600,
000
mE
700,
000
mE
550,
000
mE8,350,000 mN
8,250,000 mN
8,300,000 mN
8,200,000 mN
8,100,000 mN
8,150,000 mN
500,
000
mE
Sheet 01 Sheet 02
Sheet 03
Sheet 21Sheet 20 sheet 22Sheet 19
Sheet 23 Sheet 24 Sheet 25 Sheet 26
Sheet 27 Sheet 28 Sheet 29 Sheet 30
sheet 31 Sheet 32 Sheet 33 Sheet 34
Sheet 38 Sheet 37 Sheet 35Sheet 36
Sheet 40 Sheet 39
Sheet 18 Sheet 17 Sheet 16
Sheet 15
Sheet 46 Sheet 45 Sheet 44
Sheet 43Sheet 42Sheet 41
Sheet 14Sheet 13
Sheet 12Sheet 11Sheet 10
Sheet 09
Sheet 08
Sheet 07Sheet 06Sheet 05
Sheet 04
Sheet 63
Sheet 49Sheet 48Sheet 47
Sheet 50Sheet 51Sheet 52
Sheet 53 Sheet 54Sheet 55
Sheet 56
Sheet 57
Sheet 58
Sheet 59
Sheet 60
Sheet 61
Sheet 62
Scale 1:1,300,000
Location of Google Earth image tiles created for the study area. The sheet numbers are includedin the file names. The location of the Geoscience Australia seismic line is also shown as the thickred line.
-
Figu
re N
o. 3
Geo
scie
nce
Aus
tral
ia se
ism
ic li
ne a
nd in
terp
reta
tion
Geo
scie
nce
Aust
ralia
seis
mic
line
loca
tion
and
inte
rpre
tatio
n. T
he E
mu
Faul
t has
bee
n in
terp
rete
d as
a su
b-ve
rtiv
al p
ositi
ve fl
ower
stru
ctur
ein
a st
rike
-slip
faul
t. T
he T
awal
lah
Faul
t has
bee
n in
terp
rete
d as
a P
ost R
oper
Gro
up T
hrus
t str
uctu
re w
ith e
astw
ard
tran
spor
t.
-
3
S o l i dG e o l o g y
• Tag units with a variety of geological parameters to allow thematic maps by age, litho-type, sequence etc. to be created and analysed.
• define the fault architecture of the study area and highlight significant structures.
• define major structural block boundaries which have enhanced potential for controlling significant mineral deposits.
• define the stratigraphic sequences in the study area - differentiating recessive sequences which are potential hosts to clastic hosted base Pb / Zn mineralisation.
• attempt to identify structures active during sedimentation through recognition of associated thickness changes of the sequence.
• identify target areas based on the interpreted elements.
2 Background
A number of papers were supplied by MMG Ltd. as initial background reading to the interpretation. The following paragraphs summarise the pertinent information from each that is considered useful to constraining the current interpretation.
Rawlings et. al 2004 - Seismic Interpretation
Seismic interpretation of the southern McArthur Basin was undertaken by Geoscience Australia (Rawlings et. al 2004). The interpreted seismic section and its location are reproduced in Figure 3 (see Figure 2 for more detailed geological background for line location). Conclusions from that study include (further comments will be made on these conclusions after the interpretation resulting from this report has been presented):
• There is very little evidence for the existence of growth faults in the McArthur Basin sequence although the McArthur Group rocks do increase gradually in thickness to the east whilst the preserved Roper Group sequence increases to the west.
• East of the Narminbi Fault (incorrectly labelled as Nathan Fault in their section) the entire succession is essentially horizontal.
• There is no evidence for the existence of the Batten "Trough" or asymmetric half grabens.
• A gently east dipping carbonate ramp at McArthur times rather than a trough is suggested as a more likely environment of deposition - with third order sub-basins developed along the Emu Fault.
• The regional fault system is interpreted in terms of a series of west-dipping faults forming part of an east-propagating major thrust belt, with larger displacements in the west and diminishing to the east. The frontal thrust of the system is interpreted to lie 6km west of the Emu Fault Zone.
• The Roper Group is interpreted to lie above the westernmost thrust ramp and suggests a post-Roper Group timing for the thrusting.
-
4
S o l i dG e o l o g y
• Fault geometries are consistent with an east to northeast orientated compressional axis.
• The Emu Fault is interpreted as a near vertical strike-slip fault containing an inverted flower. The movement history on the fault comprised:
o Mid-McArthur Group sinistral shearing affecting sedimentation on transtensional fault bends.
o Post-Roper Group dextral movement inverting the earlier formed zones into positive flower structures
McArthur Basin Development - Duffett et.al.
• Roper Group thickens from 1km in the east to 5km in the west marking a change in depocentre from the McArthur Basin.
• The Buklara Sandstone is up to 300m thick in the south of the McArthur Basin.
• Basement structures established in the Barramundi Orogeny around 1850Ma subsequently had an important role in development and inversion of the McArthur Basin sequence. NNW, NW and NE trends have been identified.
• North-South extension was present during Tawallah Group deposition but was interrupted by E-W compression in mid-Tawallah Group time.
• Strike-slip movements were present during McArthur Group deposition.
• Extension resulting in block faulting was present at the commencement of the Barney Creek Formation resulting in NNW-SSE and E-W trending half grabens to the west of the Emu Fault which may have been active as a transfer fault at that time.
• An inversion event, possibly synchronous with the HYC mineralising event; the mineralisation occurs towards the top of the Barney Creek Formation. The inversion was related to NW-SE compression.
• N-S trending depocentres then redeveloped creating space for the sequence up to and including the Caranbirini Member.
• After this slow thermal subsidence seems to have been the main influence on Basin development until Roper Group deposition.
• The final deformational event affecting all Proterozoic units comprised NE-SW compression.
This paper contains a representation of the stratigraphic column that is common to most papers and was adopted as a starting point for the interpretation in this report - it has been reproduced as Figure 4.
McGoldrick et. al 2010
McGoldrick et. al. analysed litho-facies variation around the southern McArthur Basin from measured sections and drill holes resulting in the following conclusions:
• The upper McArthur Group rocks have a dominantly shallow marine / carbonate platform association.
• The Barney Creek Formation has a shale dominant deeper water association.
-
Figure No.4 McArthur Basin stratigraphic column from Duffett et.al.
-
5
S o l i dG e o l o g y
• Mapping and drill hole logging established 26 different litho-facies associations within the Barney Creek Sequence which were grouped into seven different specific depositional environments
o Continental - sheet conglomerates
o Peritidal - cauliflower chert dololutite, Coxco needles, halite clasts, microbialite.
o Shallow-subtidal - Flat pebble conglomerates, grainstone
o Deep-subtidal - Plumose structured microbialite, planar laminated dololutite, wormy dolostone, Coxco Needles
o Platform margin - Wavy microbialite.
o Slope - Clast-supported dolorudite and dolarenite, mega breccia blocks
o Basinal - red-green dolomitic siltstone, fine dolomitic sandstone, massive carbonaceous shale (+/- py), nodular argillaceous dolostone.
• The River Super Sequence comprising the stratigraphy from the Leila Sandstone to the top of the Yalco Formation has been subdivided into 3 sequences:
o The Emmerugga Depositional Sequence - Leila Sandstone to base of the Teena Dolostone
o The Barney Creek Depositional Sequence - Teena Dolomite to the top of the Reward Dolomite
o The Lynott Depositional Sequence - Caranbirini Member to the top of the Yalco Formation
• The facies developed during sinistral transpression on the Emu Fault created in N-S extension (Comment: transpression cannot occur in extensional environments) with the basin architecture controlled by the Emu, Tawallah and Hot Spring Faults which have both syn-sedimentary and post-depositional fault movements. North to NW trending segments of these structures were transtensional. Structures trending east of north were transpressional (Comment: in a N-S extensional setting the NE trending structures would be equally transtesional, it requires a strike-slip setting to create the geometry he describes - see Figure 6b).
• PB-Zn deposits developed in pyritic shales in sub-basins on the seaward side or marine side of carbonate platforms in a far-field back-arc setting.
• There is lateral continuity of the formations in the Lower McArthur River Group.
• In the vicinity of the Gorge Prospect (Figure 5a for location) a cobble conglomerate overlies the Reward Dolomite in an erosive contact. A catastrophic debris flow reworking the Lower McArthur Group rocks from a proximal source. Close to a collapsing passive margin (Comment: how does this relate to the back-arc setting mentioned above?).
• Evidence for syn-sedimentary extension at Gorge Prospect where neptunian dykes infill normal faults on the contact between the Teena Dolomite and Barney Creek Formation - indicate ENE to E-W extension (Comment: this is at 90 degrees to his extensional environment direction) . Folding related to gravitational slopes has also been interpreted - folds have northerly trending axes.
-
Figu
re N
o.5
Pros
pect
and
sub-
basi
n lo
catio
ns a
roun
d th
e H
YC
dep
osit
5a)
Loca
tion
of G
orge
Por
ospe
ct fr
om M
cGol
dric
k (20
10)
5b)
Geo
logy
aro
und
HYC
show
ing
the
trac
e of
the
ore
zone
(Fro
m N
TGS
revi
ew p
aper
)
5c)
Loca
tions
of "
sub-
basi
ns" a
roun
d H
YC.
The
term
sub-
basi
n re
fers
topr
eser
ved
stra
tigra
phy i
n sy
nclin
es ra
ther
than
dep
ositi
onal
entit
ies.
(Fro
m M
cGol
dric
k 201
0)
-
Figu
re N
o.6
McG
oldr
ick
(201
0) fa
cies
map
ping
aro
und
the
mar
gins
of t
he A
bner
Ran
geFi
gure
6a
Figu
re 6
b M
cGol
dric
k's (
2010
) str
uctu
ral m
odel
for f
orm
atio
n of
sub-
basi
ns.
In th
e te
xt h
e de
scri
bes
the s
ub-b
asin
s as f
orm
ing
in a
N-S
exte
nsio
nal r
egim
e (as
indi
cate
d by
the b
lue a
rrow
s).
How
ever
, his
mod
el is
not
com
patib
le w
ith N
-S e
xten
sion
- w
hat h
is b
lue
arro
ws s
how
is a
ctua
lly th
ere
lativ
e pla
te m
otio
n ve
ctor
s - th
is is
a si
nist
ral t
rans
tens
ion
mod
el o
n th
e Em
u Fa
ult o
rien
tatio
n.
-
6
S o l i dG e o l o g y
• There is a sharp change from the deep sub-tidal Emmerugga Sequence to shallow-water lithofacies of the Teena Dolomite superseded by basinal Barney Creek carbonaceous shales. The Barney Creek Sequence is not characterised by a layer cake stratigraphy.
• The Upper Barney Creek Sequence is characterised by a gradual shallowing.
• The most rapidly subsiding sub-basins were the HYC and Glyde sub-basins with up to 900m of pyritic shale and silt. Depo-centres formed as pull-apart basins of limited extent. Thickest sedimentation against the Tawallah Fault occurs where it trends NW (Figure 6b).
• The Hot Spring Fault was active during Barney Creek Formation sedimentation and the block between the Tawallah Fault and the Hot Spring Fault was platformal with lesser deposition (Figure 6a).
3 Interpretation
The structural/stratigraphic interpretation resulting from this project is presented as Enclosure 2 at 1:250,000 scale. The Mapinfo tables and accompanying style files and image data sets are included on the DVD accompanying this report. The Enclosures and report figures have also been included on the DVD as workspaces that can be opened directly from the DVD.
The interpretation was carried out on screen in Mapinfo using the Discover geological tools for Mapinfo. Multiple mapper windows were viewed and panned simultaneously using Discovers Maplinking tools. The main windows used during the interpretation were:
• The Google Earth image tiles (Enclosure 3). A second computer screen was used for displaying Google Earth interactively so that areas could be viewed at different scales as required. This allowed the resolution of much greater detail than is visible at the resolution of the imported tiles. During interpretation the boundaries, faults and bedding trends etc were generally viewed on the "live" google earth screen at scales of 1:10,000 to 1:25,000 and then drawn into the Mapinfo window using the lower resolution image as a guide - in this way much more detail has been included in the interpretation.
• The radiometrics image (see Enclosure 4) which contains a number a distinctive high and low radiometric packages within the sequence.
• The Landsat imagery - occasionally some of the resistant units have more characteristic signatures in this image than in the visible spectrum of the Google Earth tiles.
• Published geology at both 1:250,000 and 1:100,000 scale. During the interpretation it was noted that there are numerous attribute data errors in the 1:250,000 scale geology polygons.
The aeromagnetic data was of limited use for the exposed geology of the McArthur Group as, other than the volcanic lithologies, the signatures are generally quiet. This data set was mainly used to define major structures under thick Cretaceous or Cambrian cover and to delineate the extent of the Settlement Creek and Gold Creek Volcanics using the tilt and first vertical
-
7
S o l i dG e o l o g y
derivative images. The Roper Group stratigraphy is much more magnetic and units can be relatively easily followed - The Limmen Sandstone can be used as a marker in the tilt image. The tilt image does display an association between linear highs and some of the major faults, especially some segments of the Tawallah Fault. These highs are generally offset from the fault and suggest that the Tawallah Fault dips to the west. They may be generated by either:
• magnetite rich breccias in the faults,
• dykes intruding the faults at depth or
• slices of the Siegal Volcanics entrained in the fault or in the cores of hangingwall anticlines above the fault
The Airborne EM data was rather disappointing in that the Barney Creek Formation did not appear to have an associated consistently conductive signature. The anomaly identified by Sandfire Resources in the HYC area as related to the deposit stratigraphy seems almost certainly to be related to conductive material in McArthur River drainage system (Figure 7) - possibly from eroding the Nathan and Roper Groups. The Yalco anomaly also seems to partly have some association with the creek system. The main conductive packages are in the Nathan and Roper Groups - especially the Mainoru Formation of the Roper Group. The only formations within the McArthur Group that seem to be weakly conductive on a consistent basis are the Amelia Formation and part of the Hotspring Member.
The Stratigraphic Sequence
As mentioned above, the stratigraphic column shown in Figure 4 was used as a basis for the interpretation. When using the Discover tools for map making the styles for various stratigraphic units need to be defined in the Geostyles module or in a Colourmap that can be applied to the constructed polygons to maintain consistent tagging and graphical styles. As similar styles to the published 1:250,000 geology polygons were to be used the following methodology was used to create a Mapinfo table that could be used:
• As a colourmap table for applying graphical styles and lithology tags.
• As a lookup table summarising the characteristics and attribute data (Formation, Member, lithology, description etc) for each of the interpreted units. This lookup table can then be used to update the interpreted polygons with the attribute data so that various thematic maps can be created.
• As a legend file to be used in the final interpretation map.
This involved the following steps:
• Create a single table that contains all of the 1:250,000 geology polygons from the available sheets. This required the modification of some tables as the table structure for each map can vary (this table "McArthur 250k geol Comp lith polys.TAB" is included on the DVD).
• Once this table was created a Colourmap table was built from it using the Colourmap menu in Discover (McArthur_interp_Colourmap.TAB). This creates polygon rectangles in the mapper for each individual lithology graphical style. The lithology code for each of the polygons was chosen as an attribute. The process also encodes
-
Figure No.7 Location of AEM anomaly at HYC
Scale 1:250,000
Scale 1:250,000 Outline of early channel AEM anomaly contour attributed by Sandfire resources to hard rock Geology.Note that in the geology may the anomaly does not match the distribution of units in the interpretationwhilst the contour is a close match for surficial sediments in mcthe creek system.
-
8
S o l i dG e o l o g y
the RGB values and graphical style descriptions into the browser. This process creates more than one entry for some lithologies as they are represented with different colours in some sheets. As the interpretation is a solid geology map many of the styles are not required (those styles for superficial cover over basement rocks). An original version of the table was retained which can be used in conjunction with the 250,000 data.
• The next step is to create a lookup table that contains all of the attribute data that is associated with each of the lithology types. This is done via an SQL "Group by" query on the combined 1:250,000 geology polygons using the lithology code to list all the unique code values. The query is then saved as a stratigraphic lookup table. Duplicate entries are then removed as well as all of the entries that represent multiple Formation or Member codes where these units have not been differentiated within the polygon.
• Once these two tables were established extra entries were added for units that appear in the 1:100,000 sheets but not in the 1:250,000 maps. The codes for these units were taken off the maps.
• The two tables then needed to be merged so that the information in the attribute lookup table could be added to the Colourmap table. The Colourmap table would then be the only table required for lookup and graphical style needs. The table structure of the Colourmap table was changed to add the required fields and the fields were updated using the lithology code as a join.
• As the interpretation progressed some of the Formations or Members could be further sub-divided based on their associated signatures in the radiometrics or Google Earth images. New entries were added for these and appropriate graphic styles defined that were compatible with existing entries.
• One of the aims of the study is to investigate the distribution of various geological parameters (thickness changes, sequence distribution, location of recessive units etc.) relative to the major fault system once the interpretation was complete. To accommodate this the structure of the Colourmap table was amended to include appropriate fields. The final structure of the Colourmap table is shown in Figure 8 and the structure of the interpretation polygon table (McArthur Region interp fills final.TAB) in Figure 9. The main descriptive fields added to the polygon table are:
o Mapcode - lithology codes derived from 1:250,000 and 1:100,000 geology sheets. Codes for new units defined during the interpretation have also been added.
o Defined in current project - A "Y/N" field designed to flag those units that have been defined during this project.
o Order_Code - This is a numerical code that has been added for two purposes:
To enable the browser of the Colourmap to be sorted into stratigraphic order.
To enable easy selection of different segments of stratigraphy in the final map if required.
The following number code ranges were used (see Colourmap browser for the full list of codes assigned to subunits) - the higher the number the older the lithology:
0 - Water
-
Map
Cod
eD
efin
edO
rder
_Cod
Geo
lReg
ion
Eon
Gro
upSu
bGro
upSu
per_
Sequ
ence
Sequ
ence
Form
atio
nM
embe
rL
ithC
lass
Roc
kCat
egor
yL
ithPr
imL
ithSu
bL
ithO
ther
Eva
pori
te_
Rec
essi
ve_R
esis
tan
Lith
Des
cn1
Lith
Des
cn2
Lith
Des
cn3
Rad
iom
etri
cs_
Mag
netic
Goo
gle_
Ear
th_A
ppea
ranc
e
-Pra
j5,
720
McA
rthu
r Bas
iPr
oter
ozoi
cR
oper
Gro
upSo
uth
Nic
hols
onA
bner
San
dsto
neJa
lboi
mem
ber
Sedi
men
tary
Silic
icla
stic
mud
ston
esa
ndst
one
cong
lom
erat
Rec
essi
ve: i
nter
bedd
ed re
d m
udst
one,
ferr
Mor
e re
cess
ive
in p
lace
s str
ong
bedd
ing
-Pra
x5,
730
McA
rthu
r Bas
iPr
oter
ozoi
cR
oper
Gro
upSo
uth
Nic
hols
onA
bner
San
dsto
neA
rnol
d Sa
ndst
one
Mem
ber
Sedi
men
tary
Silic
icla
stic
sand
ston
eR
esis
tant
Rid
ge-f
orm
ing:
pse
udo-
kars
tical
ly w
eath
eW
ell b
edde
d rid
ge w
hite
-gre
y
-Prr
5,80
0M
cArt
hur B
asi
Prot
eroz
oic
Rop
er G
roup
Sout
h N
icho
lson
Cra
wfo
rd F
orm
atio
n (N
T)Se
dim
enta
rySi
licic
last
icsa
ndst
one
silts
tone
Res
ista
nt-P
rr: R
idge
-for
min
g: re
d-br
own,
fine
-gra
ico
nvol
ute
beds
Hig
hW
ell b
edde
d un
it us
ually
on
scar
ps
-Pru
5,85
0M
cArt
hur B
asi
Prot
eroz
oic
Rop
er G
roup
Sout
h N
icho
lson
Mai
noru
For
mat
ion
Sedi
men
tary
Silic
icla
stic
sand
ston
esi
ltsto
neR
eces
sive
-Pru
: Rec
essi
ve: r
ed-b
row
n m
icac
eous
silt
fine-
grai
ned
sand
ston
e an
d si
ltsV
ery
cond
uctiv
e un
it po
orly
exp
osed
flat
exp
anse
s
-Prg
5,86
0M
cArt
hur B
asi
Prot
eroz
oic
Rop
er G
roup
Sout
h N
icho
lson
Mai
noru
For
mat
ion
Kilg
our S
ands
tone
Mem
beSe
dim
enta
rySi
licic
last
icsa
ndst
one
Res
ista
ntFo
und
in A
bner
Ran
ge re
sist
ant s
ands
tone
ver
y co
n
-Pri
5,90
0M
cArt
hur B
asi
Prot
eroz
oic
Rop
er G
roup
Sout
h N
icho
lson
Lim
men
San
dsto
neSe
dim
enta
rySi
licic
last
icar
enite
Res
ista
nt-P
ri: R
idge
-for
min
g: fi
ne-g
rain
ed, s
truc
tutr
ough
cro
ss-b
eds,
tool
mar
ks, f
Ver
y Lo
wM
ediu
mC
hara
cter
istic
san
dsto
ne ri
dge
- gen
eral
ly c
ream
w
-Pnn
6,10
0M
cArt
hur B
asi
Prot
eroz
oic
Nat
han
Gro
upD
oom
Man
tung
ula
Form
atio
nSe
dim
enta
rySi
licic
last
ic se
dim
ent
Silts
tone
Rec
essi
veM
icac
eous
silts
tone
Low
Flat
poo
rly
expo
sed
-Png
6,60
0M
cArt
hur B
asi
Prot
eroz
oic
Nat
han
Gro
upW
ide
Dun
gam
inni
e Fo
rmat
ion
Sedi
men
tary
Che
mic
aldo
lare
nite
dolo
ston
esa
ndst
one
Res
ista
ntU
pper
: lam
inat
ed s
andy
dol
aren
ite a
nd d
oM
ediu
mLo
w o
live
yello
w ri
dges
-Pnz
6,70
0M
cArt
hur B
asi
Prot
eroz
oic
Nat
han
Gro
upW
ide
Bal
bari
ni D
olos
tone
Sedi
men
tary
Che
mic
aldo
lolu
tite
y-P
nz: G
ener
ally
rece
ssiv
e: d
olol
utite
, stro
man
d in
pla
ces
caul
iflow
er c
hert
Low
Poor
ly e
xpos
ed a
nd re
cess
ive
- poo
rly b
edde
d - l
ow
-Pny
6,80
0M
cArt
hur B
asi
Prot
eroz
oic
Nat
han
Gro
upLa
wn
Smyt
he S
ands
tone
Sedi
men
tary
Silic
icla
stic
cong
lom
erat
esa
ndst
one
Rid
ge-f
orm
ing:
mas
sive
, coa
rse
poly
mic
t V
ery
Low
Thic
kly
bedd
ed g
rey
sand
ston
e ri
dges
-Pk
6,90
0M
cArt
hur B
asi
Prot
eroz
oic
Nat
han
Gro
upLa
wn
Kar
ns D
olom
iteSe
dim
enta
ryC
hem
ical
sed
imen
tD
olom
ite/D
olch
ert
ySt
rom
atol
itic,
eva
pori
tic, i
ntra
clas
tic a
nd o
-Pk>
s6,
950
McA
rthu
r Bas
iPr
oter
ozoi
cN
atha
n G
roup
Law
nLo
wer
Kar
ns D
olom
iteSe
dim
enta
rySi
licic
last
ic se
dim
ent
Sand
ston
eW
hite
fine
- to
med
ium
-gra
ined
qua
rtzo
se
-Pm
7,00
0M
cArt
hur B
asi
Prot
eroz
oic
McA
rthu
r Gro
upLa
wn
Und
ivid
ed M
cArt
hur G
roup
FF
McA
rthu
r Gro
up:u
ndiv
ided
at m
ap sc
ale;
s
-Pm
m7,
150
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Law
nA
mos
For
mat
ion
Sedi
men
tary
Che
mic
aldo
lost
one
silts
tone
sand
ston
eR
eces
sive
Upp
er: m
assi
ve k
arst
ic-w
eath
erin
g da
rk-g
Rec
essi
ve re
d br
own
- res
tric
ted
deve
lopm
ent
-Pm
o7,
200
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Ter
mLo
okin
g G
lass
For
mat
ion
Sedi
men
tary
Che
mic
aldo
lost
one
dola
reni
teR
esis
tant
Rec
essi
ve:s
ilici
fied
,com
mon
ly st
rom
atol
iM
ediu
mW
ell b
edde
d w
ith c
ream
ban
ding
- re
sist
ant
-Pm
r7,
250
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArth
ur G
roup
Bat
ten
Ter
mSt
retto
n Sa
ndst
one
Sedi
men
tary
Silic
icla
stic
sand
ston
eR
esis
tant
Rid
ge-f
orm
ing:
fine
-to
med
ium
-gra
ined
, tM
ediu
mC
ream
gre
y re
sist
ant s
ands
tone
can
be
thic
kly
bedd
-Pm
r>2
y7,
260
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArth
ur G
roup
Bat
ten
Ter
mSt
retto
n Sa
ndst
one
Stre
tton
Upp
erSe
dim
enta
rySi
licic
last
icsa
ndst
one
Res
ista
ntR
idge
-for
min
g:fi
ne-to
med
ium
-gra
ined
, tH
igh
Cre
am y
ello
w re
ssita
nt s
ands
tone
- hi
gh to
med
ium
-Pm
r>1
y7,
270
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Ter
mSt
retto
n Sa
ndst
one
Stre
tton
Low
erSe
dim
enta
rySi
licic
last
icsa
ndst
one
Res
ista
ntR
idge
-for
min
g:fin
e-to
med
ium
-gra
ined
, tH
igh
Red
bro
wn
colo
urs
- med
ium
hig
h ra
d w
ith H
igh
b
-Pm
nj7,
300
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Yal
co F
orm
atio
nSe
dim
enta
ryC
hem
ical
dolo
ston
edo
lare
nite
sand
ston
ey
Res
ista
ntR
idge
-for
min
g:th
inly
inte
rbed
ded
stro
mat
Low
Smoo
th o
live
slig
htly
resi
stan
t
-Pm
nj>2
y7,
310
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Yal
co F
orm
atio
nY
alco
Upp
erSe
dim
enta
ryC
hem
ical
dolo
ston
edo
lare
nite
sand
ston
ey
Rec
essi
veR
idge
-for
min
g:th
inly
inte
rbed
ded
stro
mat
Low
Red
-Bro
wn
rece
ssiv
e m
ed ra
d va
riab
le to
low
rad
a
-Pm
nj>1
y7,
320
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Yal
co F
orm
atio
nY
alco
Low
erSe
dim
enta
ryC
hem
ical
dolo
ston
edo
lare
nite
sand
ston
ey
Res
ista
ntR
idge
-for
min
g:th
inly
inte
rbed
ded
stro
mat
Ver
y Lo
wM
Ass
ive
resi
stan
t san
dsto
ne p
inki
sh c
ream
col
our
-Pm
nd7,
410
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Lyno
tt Fo
rmat
ion
Don
nega
n M
embe
rSe
dim
enta
rySi
licic
last
icsi
ltsto
nesa
ndst
one
dola
reni
teR
eces
sive
/ R
esR
eces
sive
:dol
omiti
c si
ltsto
ne,fi
ne-t
ocoa
rsV
ery
Hig
hG
ener
ally
low
lyin
g w
ith b
eddi
ng e
vide
nt w
here
ex
-Pm
nh7,
420
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Lyno
tt Fo
rmat
ion
Hot
Spr
ing
Mem
ber
Sedi
men
tary
Silic
icla
stic
silts
tone
sand
ston
edo
lare
nite
yR
esis
tant
Rid
ge-f
orm
ing:
thin
-bed
ded
dolo
nitic
silt
ssa
ndst
ones
are
ripp
led
and
cros
sV
ery
Low
Mas
sive
oliv
e gr
een
poor
ly b
edde
d w
eakl
y re
sist
an
-Pm
nh>3
y7,
423
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Lyno
tt Fo
rmat
ion
Hot
Spr
ing
Mem
ber 3
Sedi
men
tary
Silic
icla
stic
silts
tone
sand
ston
edo
lare
nite
yR
eces
sive
Rid
ge-f
orm
ing:
thin
-bed
ded
dolo
nitic
silt
ssa
ndst
ones
are
ripp
led
and
cros
sV
ery
Low
Dar
k ol
ive
slig
htly
rece
ssiv
e lo
w ra
d si
gnat
ures
-Pm
nh>2
y7,
424
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Lyno
tt Fo
rmat
ion
Hot
Spr
ing
Mem
ber 2
Sedi
men
tary
Silic
icla
stic
silts
tone
sand
ston
edo
lare
nite
yR
esis
tant
Rid
ge-f
orm
ing:
thin
-bed
ded
dolo
nitic
silt
ssa
ndst
ones
are
ripp
led
and
cros
sLo
wG
rey
yello
w sa
ndst
one
unit
resi
stan
t
-Pm
nh>1
y7,
425
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Lyno
tt Fo
rmat
ion
Hot
Spr
ing
Mem
ber 1
Sedi
men
tary
Silic
icla
stic
silts
tone
sand
ston
edo
lare
nite
yR
esis
tant
Rid
ge-f
orm
ing:
thin
-bed
ded
dolo
nitic
silt
ssa
ndst
ones
are
ripp
led
and
cros
sH
igh
Bed
ded
yello
w a
nd c
ream
uni
ts m
oder
atel
y re
sist
an
-Pm
nc7,
440
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Lyno
tt Fo
rmat
ion
Car
anbi
rini M
embe
rSe
dim
enta
rySi
licic
last
icsi
ltsto
nedo
lare
nite
brec
cia
yR
eces
sive
Rec
essi
ve:th
in-b
edde
d do
lom
itic
silts
tone
Hig
hY
ello
w a
nd li
ght g
reen
col
ours
- be
dded
with
cha
ra
-Pm
nc>5
y7,
445
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Lyno
tt Fo
rmat
ion
Car
anbi
rini M
embe
r 5Se
dim
enta
rySi
licic
last
icsi
ltsto
nedo
lare
nite
brec
cia
yR
eces
sive
:thin
-bed
ded
dolo
miti
c si
ltsto
neH
igh
Gen
eral
ly w
ell e
xpos
ed -
less
wel
l bed
ded
light
oli
-Pm
nc>4
y7,
446
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Lyno
tt Fo
rmat
ion
Car
anbi
rini M
embe
r 4Se
dim
enta
rySi
licic
last
icsi
ltsto
nedo
lare
nite
brec
cia
yR
esis
tant
Rec
essi
ve:th
in-b
edde
d do
lom
itic
silts
tone
Ver
y H
igh
Wel
l bed
ded
crea
m a
nd g
reen
ban
ds fo
rmin
g rid
ge
-Pm
nc>3
y7,
447
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Lyno
tt Fo
rmat
ion
Car
anbi
rini M
embe
r 3Se
dim
enta
rySi
licic
last
icsi
ltsto
nedo
lare
nite
brec
cia
yR
eces
sive
Rec
essi
ve:th
in-b
edde
d do
lom
itic
silts
tone
Low
Rec
essi
ve si
mila
r to
pmnc
>1
-Pm
nc>2
y7,
448
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Lyno
tt Fo
rmat
ion
Car
anbi
rini M
embe
r 2Se
dim
enta
rySi
licic
last
icsi
ltsto
nedo
lare
nite
brec
cia
yR
esis
tant
Rec
essi
ve:th
in-b
edde
d do
lom
itic
silts
tone
Hig
hW
ell b
edde
d lo
w b
road
ridg
es -
crea
m b
andi
ng -
si
-Pm
nc>1
y7,
449
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Bat
ten
Riv
erLy
nott
Lyno
tt Fo
rmat
ion
Car
anbi
rini M
embe
r 1Se
dim
enta
rySi
licic
last
icsi
ltsto
nedo
lare
nite
brec
cia
yR
eces
sive
Rec
essi
ve:th
in-b
edde
d do
lom
itic
silts
tone
Low
Gen
eral
ly re
cess
ive
and
poor
ly e
xpos
ed
-Pm
x7,
450
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erB
arne
y C
reek
Rew
ard
Dol
osto
neSe
dim
enta
ryC
hem
ical
dolo
lutit
ey
Res
ista
nt-P
mx:
Rid
ge-f
orm
ing
and
rece
ssiv
e: d
olol
sulf
ate
evap
orite
s; o
ncoi
ds, o
oid
Ver
y H
igh
Mas
sive
som
etim
es c
ream
col
oure
d -
brow
n ri
dge
-Pm
x>1
7,46
0M
cArt
hur B
asi
Prot
eroz
oic
McA
rthu
r Gro
upU
mbo
loog
aR
iver
Bar
ney
Cre
ekR
ewar
d D
olos
tone
Low
Rad
Sedi
men
tary
Che
mic
aldo
lolu
tite
yR
esis
tant
-Pm
x: R
idge
-for
min
g an
d re
cess
ive:
dol
olLo
wLo
w ra
d si
gnat
ure
in v
icin
ity o
f HY
C
-Pm
q7,
500
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erB
arne
y C
reek
Bar
ney
Cre
ek F
orm
atio
nM
etam
orph
icM
eta-
chem
ical
sed
ime
shal
esi
ltsto
ney
Rec
essi
ve-P
mq:
Rec
essi
ve: t
hinl
y be
dded
to la
min
aV
ery
Hig
hG
ener
ally
poo
rly
expo
sed
- not
obv
ious
ly b
edde
d -
-Pm
p7,
550
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erB
arne
y C
reek
Teen
a D
olos
tone
Sedi
men
tary
Che
mic
aldo
lolu
tite
Res
ista
nt-P
mp:
Rec
essi
ve: t
hinl
y be
dded
to la
min
aV
ery
Hig
hM
assi
ve s
light
ly re
sist
ant s
ome
wea
k be
ddin
g bu
ff
-Pm
pc7,
560
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erB
arne
y C
reek
Teen
a D
olom
iteC
oxco
Dol
omite
Mem
ber
Sedi
men
tary
Che
mic
aldo
lost
one
shal
esa
ndst
one
y-P
mpc
: Rec
essi
ve:g
rey
crys
talli
ne d
olol
utV
ery
Hig
hM
assi
ve sl
ight
ly re
cess
ive
-Pm
e7,
600
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erEm
mer
ugga
Emm
erug
ga D
olos
tone
Sedi
men
tary
Che
mic
aldo
lost
one
Res
ista
nt-P
me:
Und
ivid
ed E
mm
erug
ga D
olos
tone
Low
-Pm
ei7,
610
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erEm
mer
ugga
Emm
erug
ga D
olom
iteM
itche
ll Y
ard
Dol
omite
MSe
dim
enta
ryC
hem
ical
dolo
ston
eR
esis
tant
-Pm
ei: G
ener
ally
rece
ssiv
e:m
assi
ve,d
ark
gV
ery
Low
Bet
ter b
edde
d ne
ar E
mu
Faul
t - b
ut m
ore
mas
sive
a
-Pm
ea7,
630
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erEm
mer
ugga
Emm
erug
ga D
olom
iteM
ara
Dol
omite
Mem
ber
Sedi
men
tary
Che
mic
aldo
lost
one
silts
tone
dola
reni
tey
Res
ista
nt-P
mea
: Rid
ge-f
orm
ing:
dolo
lutit
e,st
rom
ato
Low
Mas
sive
gen
eral
ly e
xpos
ed b
ut n
ot ri
ges -
can
be
g
-Pm
e>1
y7,
640
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erEm
mer
ugga
Emm
erug
ga D
olos
tone
Emm
erug
ga H
ighR
adSe
dim
enta
ryC
hem
ical
dolo
ston
eR
esis
tant
-Pm
e: U
ndiv
ided
Em
mer
ugga
Dol
osto
neH
igh
Hig
her r
ad s
igna
ture
s O
ilve
colo
urs
- nea
r Em
u Fa
-Pm
f7,
650
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erEm
mer
ugga
Myr
tle S
hale
Sedi
men
tary
Silic
icla
stic
silts
tone
yR
eces
sive
-Pm
f: R
eces
sive
: thi
nly
bedd
ed to
lam
inat
Hig
hM
yrtle
shal
e ge
nera
lly fl
at re
cess
ive
- cre
am g
rey
t
-Pm
f>1
y7,
660
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erEm
mer
ugga
Myr
tle S
hale
Myr
tle S
ands
tone
Sedi
men
tary
Silic
icla
stic
silts
tone
yR
esis
tant
-Pm
f: R
eces
sive
: thi
nly
bedd
ed to
lam
inat
Hig
hSa
ndst
one
ridg
e so
met
imes
at t
op o
f Myr
tle S
hale
-Pm
i7,
700
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erEm
mer
ugga
Leila
San
dsto
neSe
dim
enta
rySi
licic
last
icsa
ndst
one
Res
ista
nt-P
mi:
Rec
essi
ve a
nd ri
dge-
form
ing:
dar
k g
Hig
hR
esis
tant
sand
ston
e ri
dge.
-Pm
i>1a
y7,
705
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erEm
mer
ugga
Leila
San
dsto
neLe
ila B
ase
Sedi
men
tary
Silic
icla
stic
sand
ston
eR
eces
sive
-Pm
i: R
eces
sive
and
ridg
e-fo
rmin
g: d
ark
gLo
wR
ed b
row
n re
cess
ive
sim
ilar t
o -P
mt>
1
-Pm
i>1
y7,
710
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erEm
mer
ugga
Leila
San
dsto
neLe
ila L
ower
Sedi
men
tary
Silic
icla
stic
sand
ston
eR
esis
tant
-Pm
i: R
eces
sive
and
ridg
e-fo
rmin
g: d
ark
gH
igh
Buf
f san
dsto
ne ri
dge
som
ewha
t sim
ilar t
o Ta
tool
a
-Pm
i>2
y7,
720
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erEm
mer
ugga
Leila
San
dsto
neLe
ila C
entra
lSe
dim
enta
rySi
licic
last
icsa
ndst
one
Rec
essi
ve-P
mi:
Rec
essi
ve a
nd ri
dge-
form
ing:
dar
k g
Hig
hD
ark
flat
and
rece
ssiv
e
-Pm
i>2a
y7,
725
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erEm
mer
ugga
Leila
San
dsto
neLe
ila C
entra
l 2Se
dim
enta
rySi
licic
last
icsa
ndst
one
-Pm
i: R
eces
sive
and
ridg
e-fo
rmin
g: d
ark
gLo
wSl
ight
ly re
cess
ive
can
have
gre
y "E
mm
erug
ga"
app
-Pm
i>3
y7,
730
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Riv
erEm
mer
ugga
Leila
San
dsto
neLe
ila U
pper
Sedi
men
tary
Silic
icla
stic
sand
ston
eR
esis
tant
-Pm
i: R
eces
sive
and
ridg
e-fo
rmin
g: d
ark
gH
igh
Sand
ston
e rid
ge s
imila
r to
-Pm
i>1
-Pm
t7,
750
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Lore
ttaTo
ogan
inie
For
mat
ion
Sedi
men
tary
Che
mic
aldo
lolu
tite
yR
eces
sive
-Pm
t: G
ener
ally
rece
ssiv
e: d
olol
utite
, stro
pseu
dom
orph
s aft
er g
ypsu
m a
nH
igh
Stro
ngly
bed
ded
and
quite
wel
l exp
osed
-Pm
t>1
y7,
760
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Lore
ttaTo
ogan
inie
For
mat
ion
Toog
anin
ie L
ower
Sedi
men
tary
Che
mic
aldo
lolu
tite
yR
eces
sive
-Pm
t: G
ener
ally
rece
ssiv
e: d
olol
utite
, stro
pseu
dom
orph
s aft
er g
ypsu
m a
nLo
wLo
w ra
d zo
ne o
n co
ntac
t to
Tato
ola
- mor
e sh
ale
ri
-Pm
t>2
y7,
770
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Lore
ttaTo
ogan
inie
For
mat
ion
Toog
anin
ie M
arke
rSe
dim
enta
ryC
hem
ical
dolo
lutit
ey
Res
ista
nt-P
mt:
Gen
eral
ly re
cess
ive:
dol
olut
ite, s
tro
pseu
dom
orph
s aft
er g
ypsu
m a
nH
igh
Thin
pos
s san
dsto
ne m
arke
r pos
s sim
ilar t
o Ta
tool
a
-Pm
t>3
y7,
780
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Lore
ttaTo
ogan
inie
For
mat
ion
Toog
anin
ie R
ough
Sedi
men
tary
Che
mic
aldo
lolu
tite
yR
esis
tant
-Pm
t: G
ener
ally
rece
ssiv
e: d
olol
utite
, str
ops
eudo
mor
phs a
fter
gyp
sum
an
Hig
hR
esis
tant
poo
rly
bedd
ed fa
cies
of T
ooga
nini
e
-Pm
d7,
800
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Lore
ttaTa
tool
a Sa
ndst
one
Sedi
men
tary
Silic
icla
stic
sand
ston
ey
Res
ista
nt-P
md:
Upp
er: r
idge
form
ing:
mai
nly
med
ith
inly
bed
ded,
usu
ally
fine
-gra
im
ud c
last
imp
Hig
hO
rang
e/ye
llow
sm
ooth
san
dsto
ne ri
dge
-Pm
d>3
y7,
810
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Lore
ttaTa
tool
a Sa
ndst
one
Tato
ola
Sand
ston
e U
pper
Sedi
men
tary
Silic
icla
stic
sand
ston
ey
Res
ista
ntU
pper
: rid
ge fo
rmin
g: m
ainl
y m
ediu
m-g
raH
igh
Ora
nge
yello
w s
ands
tone
ridg
e m
arke
r - th
icke
r in
-Pm
d>2
y7,
820
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Lore
ttaTa
tool
a Sa
ndst
one
Tato
ola
Sand
ston
e C
entr
alSe
dim
enta
rySi
licic
last
icsa
ndst
one
yR
eces
sive
Hig
hFl
at a
rea
betw
een
sand
ston
e ri
dges
- lo
w ra
d in
sou
-Pm
d>1
y7,
830
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Lore
ttaTa
tool
a Sa
ndst
one
Tato
ola
Sand
ston
e Lo
wer
Sedi
men
tary
Silic
icla
stic
sand
ston
ey
Res
ista
ntLo
wer
: rid
ge-f
orm
ing:
tabu
lar,
thin
ly b
edH
igh
Low
Ora
nge
yello
w s
ands
tone
ridg
e m
arke
r - th
icke
r in
-Pm
a7,
850
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArth
ur G
roup
Um
bolo
oga
Gun
Am
elia
Dol
osto
neSe
dim
enta
ryC
hem
ical
dolo
lutit
edo
lare
nite
-Pm
a: R
eces
sive
: stro
mat
oliti
c do
lolu
tite
(de
velo
pmen
t of s
ider
itic
'mar
ble
Low
Dar
k re
d-br
own
wea
kly
bedd
ed o
r mas
sive
-Pm
a>1
y7,
860
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArth
ur G
roup
Um
bolo
oga
Gun
Am
elia
Dol
osto
neA
mel
ia D
olos
tone
Hig
h R
aSe
dim
enta
ryC
hem
ical
dolo
lutit
edo
lare
nite
-Pm
a: R
eces
sive
: stro
mat
oliti
c do
lolu
tite
(de
velo
pmen
t of s
ider
itic
'mar
ble
Hig
hG
ener
ally
mas
sive
and
exp
osed
gre
y to
buf
f col
our
-Pm
l7,
900
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Gun
Mal
lapu
nyah
For
mat
ion
Met
amor
phic
Met
a-ch
emic
al s
edim
esh
ale
y-P
ml:
Mai
nly
rece
ssiv
e: re
d to
pur
ple
dolo
desi
ccat
ion
crac
ks, a
nd g
ypsu
mH
igh
in w
est l
ow in
eas
t
-Pm
l>4
y7,
910
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Gun
Mal
lapu
nyah
For
mat
ion
Mal
lapu
nyah
Top
Met
amor
phic
Met
a-ch
emic
al s
edim
esh
ale
yR
esis
tant
-Pm
l: M
ainl
y re
cess
ive:
red
to p
urpl
e do
lode
sicc
atio
n cr
acks
, and
gyp
sum
Low
Low
Mas
sive
buf
f rid
ge -
sand
ston
e or
dol
omite
- va
riab
-Pm
l>3
y7,
920
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Gun
Mal
lapu
nyah
For
mat
ion
Mal
lapu
nyah
Upp
erM
etam
orph
icM
eta-
chem
ical
sed
ime
shal
ey
Rec
essi
ve-P
ml:
Mai
nly
rece
ssiv
e: re
d to
pur
ple
dolo
desi
ccat
ion
crac
ks, a
nd g
ypsu
mH
igh
Low
Bro
wn
low
lyin
g w
eakl
y be
dded
-Pm
l>2
y7,
930
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Gun
Mal
lapu
nyah
For
mat
ion
Mal
lapu
nyah
Cen
tral
Met
amor
phic
Met
a-ch
emic
al s
edim
esh
ale
yR
esis
tant
-Pm
l: M
ainl
y re
cess
ive:
red
to p
urpl
e do
lode
sicc
atio
n cr
acks
, and
gyp
sum
Low
Low
Mas
sive
buf
f rid
ge -
sand
ston
e or
dol
omite
- va
riab
-Pm
l>1
y7,
940
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Gun
Mal
lapu
nyah
For
mat
ion
Mal
lapu
nyah
Low
erM
etam
orph
icM
eta-
chem
ical
sed
ime
shal
ey
Rec
essi
ve-P
ml:
Mai
nly
rece
ssiv
e: re
d to
pur
ple
dolo
desi
ccat
ion
crac
ks, a
nd g
ypsu
mLo
w M
ediu
mLo
wB
edde
d da
rk b
row
n ge
nera
lly lo
w ly
ing
-Pm
s7,
950
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArth
ur G
roup
Um
bolo
oga
Gun
Mas
terto
n Sa
ndst
one
Sedi
men
tary
Silic
icla
stic
sand
ston
ey
Res
ista
nt-P
ms:
Rid
ge-f
orm
ing:
pin
k, b
row
n an
d bu
min
or u
nits
; dis
tinct
ly fe
rrug
ino
Ver
y Lo
wM
assi
ve w
hite
yel
low
sand
ston
e - v
ery
thic
kly
bed
-Pm
s>3
y7,
960
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Gun
Mas
terto
n Sa
ndst
one
Mas
tert
on U
pper
Sedi
men
tary
Silic
icla
stic
sand
ston
ey
Res
ista
nt-P
ms:
Rid
ge-f
orm
ing:
pin
k, b
row
n an
d bu
min
or u
nits
; dis
tinct
ly fe
rrug
ino
Ver
y Lo
wD
arke
bro
wn
less
ort
ho ss
t con
tent
less
resi
stan
t - m
-Pm
s>2
y7,
970
McA
rthu
r Bas
iPr
oter
ozoi
cM
cArt
hur G
roup
Um
bolo
oga
Gun
Mas
terto
n Sa
ndst
one
Mas
tert
on C
entr
alSe
dim
enta
rySi
licic
last
icsa
ndst
one
yR
eces
sive
-Pm
s: R
idge
-for
min
g: p
ink,
bro
wn
and
bum
inor
uni
ts; d
istin
ctly
ferr
ugin
oH
igh
Dar
k an
d re
cess
ive
may
be
volc
anic
or d
oler
ite?
-Pth
8,00
0M
cArt
hur B
asi
Prot
eroz
oic
Taw
alla
h G
roup
Taw
alla
hH
obbl
echa
in R
hyol
iteV
olca
nic
Maf
ic e
xtru
sive
Rhy
olite
Pink
, por
phyr
itic
(K-f
elds
par-
quar
tz),
mas
-Pt
8,00
0M
cArt
hur B
asi
Prot
eroz
oic
Taw
alla
h G
roup
Taw
alla
hU
ndif
fere
ntia
ted
Taw
alla
h G
Igne
ous
Maf
ic e
xtru
sive
basa
ltsa
ndst
one
-Pt:
Und
ivid
ed T
awal
lah
Gro
up
-Ptc
8,05
0M
cArt
hur B
asi
Prot
eroz
oic
Taw
alla
h G
roup
Taw
alla
hEc
ho S
ands
tone
Sedi
men
tary
Silic
icla
stic
sedi
men
tSa
ndst
one
Pink
, med
ium
-gra
ined
, loc
ally
peb
bly,
lith
-Ptc
u8,
051
McA
rthu
r Bas
iPr
oter
ozoi
cTa
wal
lah
Gro
upTa
wal
lah
Echo
San
dsto
nePu
ngal
ina
Mem
ber
Sedi
men
tary
Silic
icla
stic
sedi
men
tC
ongl
omer
ate
Low
er p
ebbl
e to
bou
lder
con
glom
erat
e w
i
-Ptc
u>1
8,05
2M
cArt
hur B
asi
Prot
eroz
oic
Taw
alla
h G
roup
Taw
alla
hEc
ho S
ands
tone
Low
er P
unga
lina
Mem
ber
Sedi
men
tary
Silic
icla
stic
sedi
men
tLi
thic
Are
nite
Pink
med
ium
-gra
ined
lith
ic s
ands
tone
wit
-Ptc
u>2
8,05
3M
cArt
hur B
asi
Prot
eroz
oic
Taw
alla
h G
roup
Taw
alla
hEc
ho S
ands
tone
Upp
er P
unga
lina
Mem
ber
Sedi
men
tary
Silic
icla
stic
sedi
men
tD
olom
itic
Silt
Dol
omiti
c si
ltsto
ne a
nd fi
ne-g
rain
ed s
ands
-Ptt
8,06
0M
cArt
hur B
asi
Prot
eroz
oic
Taw
alla
h G
roup
Taw
alla
hTa
num
birin
i Rhy
olite
Igne
ous
Fels
ic e
xtru
sive
rhyo
lite
Rec
essi
ve: d
eepl
y w
eath
ered
, por
phyr
itic
Ver
y H
igh
Buf
f col
oure
d w
eakl
y re
sist
ant
-Ptn
8,10
0M
cArt
hur B
asi
Prot
eroz
oic
Taw
alla
h G
roup
Taw
alla
hW
unun
man
tyal
a Sa
ndst
one
Sedi
men
tary
Silic
icla
stic
sand
ston
eR
idge
-for
min
g: re
d to
mau
ve-g
rey,
loca
llysh
ale
inte
rbed
sLo
wLo
wG
ener
ally
qui
te d
ark
brow
n an
d fl
at n
ot v
ery
resi
st
-Ptn
w8,
110
McA
rthu
r Bas
iPr
oter
ozoi
cTa
wal
lah
Gro
upTa
wal
lah
Wun
unm
anty
ala
Sand
ston
eW
ural
iwun
tya
Mem
ber
Sedi
men
tary
Silic
icla
stic
sedi
men
tSa
ndst
one
Mud
ston
eR
esis
tant
Fine
-gra
ined
and
rare
ly m
ediu
m-g
rain
ed s
mar
ks, f
lute
cas
tsV
ery
Low
Low
Less
resi
stan
t tha
n M
aste
rton
- cr
eam
gre
y m
assi
ve
-Ptn
>1y
8,12
0M
cArt
hur B
asi
Prot
eroz
oic
Taw
alla
h G
roup
Taw
alla
hW
unun
man
tyal
a Sa
ndst
one
Wun
unm
anty
ala
1Se
dim
enta
rySi
licic
last
icsa
ndst
one
Res
ista
ntR
idge
-for
min
g: re
d to
mau
ve-g
rey,
loca
llysh
ale
inte
rbed
sV
ery
Low
Low
Cre
am y
ello
w m
assi
ve sa
ndst
one
-Ptg
8,20
0M
cArt
hur B
asi
Prot
eroz
oic
Taw
alla
h G
roup
Taw
alla
hG
old
Cre
ek V
olca
nics
Igne
ous
Maf
ic e
xtru
sive
basa
ltR
esis
tant
-Ptg
: Rec
essi
ve: a
myg
dalo
idal
ves
icul
ar b
auto
clas
tic, f
low
-ban
ded
rhyo
litV
ery
Hig
h1V
D N
oiM
ore
resi
stnt
with
cre
am c
olou
rs a
nd ro
ughe
r tex
tu
-Pte
8,25
0M
cArt
hur B
asi
Prot
eroz
oic
Taw
alla
h G
roup
Taw
alla
hSe
ttlem
ent C
reek
Vol
cani
csIg
neou
sM
afic
ext
rusi
veba
salt
dole
rite
Rec
essi
ve-P
te: R
eces
sive
: red
-bro
wn
to d
ark
grey
spdo
lolu
tite
brec
cia;
pot
ash-
met
asV
ery
Hig
h1V
D N
oiO
live-
Yel
low
flat
mas
sive
-Ptlr
8,30
0M
cArt
hur B
asi
Prot
eroz
oic
Taw
alla
h G
roup
Taw
alla
hR
osie
Cre
ek S
ands
tone
Sedi
men
tary
Silic
icla
stic
sand
ston
esi
ltsto
neR
esis
tant
Rid
ge-f
orm
ing:
san
dsto
ne, v
ery
fine-
to c
oV
ery
Low
Low
Smoo
th s
ands
tone
pin
k br
own
high
mas
sive
-Ptlr
>3y
8,31
0M
cArt
hur B
asi
Prot
eroz
oic
Taw
alla
h G
roup
Taw
alla
hR
osie
Cre
ek S
ands
tone
Ros
ie C
reek
San
dsto
ne U
pSe
dim
enta
rySi
licic
last
icsa
ndst
one
silts
tone
Res
ista
ntR
idge
-for
min
g: s
ands
tone
, ver
y fin
e- to
co
Ver
y Lo
wLo
ww
hite
-bro
wm
spec
kele
d ri
dges
mas
sive
-Ptlr
>2y
8,32
0M
cArt
hur B
asi
Prot
eroz
oic
Taw
alla
h G
roup
Taw
alla
hR
osie
Cre
ek S
ands
tone
Ros
ie C
reek
San
dsto
ne C
enSe
dim
enta
rySi
licic
last
icsa
ndst
one
silts
tone
Rec
essi
veR
idge
-for
min
g: s
ands
tone
, ver
y fin
e- to
co
Low
Low
Rec
essi
ve b
etw
een
ridg
es
Figu
re N
o.8
Stru
ctur
e of
Col
ourM
ap ta
ble
(gra
phic
def
initi
on fi
elds
not
show
n)
-
Map
Cod
eD
efin
ed_
Ord
er_C
ode
Geo
lReg
ion
Eon
Gro
upSu
bGro
upSu
per_
Sequ
ence
Sequ
ence
Form
atio
nM
embe
rL
ithC
lass
Roc
kCat
egor
yL
ithPr
imL
ithSu
bL
ithO
ther
Eva
pori
te_E
