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Applications of high resolution airborne magnetic and radiometric data in the Barberton greenstone belt of South Africa.Moore, Chris January 1994 (has links)
A Dissertation Submitted to the Faculty of Science University of the Witwatersrand, Johannesburg for the degree of Master of Science / AC 2018
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Processing remotely sensed data for geological content over a part of the Barberton Greenstone Belt, Republic of South Africa.Cloete, Derik January 1993 (has links)
Various methods and techniques developed by researchers worldwide for
enhancement and processing ATM, MSS· and TM remotely sensed data are
tested. on LANDSAT 5 Thematic Mapper data from a part of the Barberton
Greenstone Belt straddling the border between the Republic of South Africa and
the Kingdom of Swaziland.
Various enhancement techniques employed to facilitate the extraction of
structural features and lineaments, and the findings Of the ensuing
photogeologlcal interpretation are compared with existing geological maps~
Methods for the detection of zones of hydrothermal alteration. are also
considered.
The reflectance from vegetation, both natural and cultivated, and the possible
reduction of the interference caused by this reflectance, are considered in detail.
Partial unmixing of reflectances through the use of various methods and
techniques, some of which are readily available from the literature, are
performed and its effectiveness tested. Since large areas within the study area
are covered by plantations, the interfereiice from the two types of vegetation
present (i.e. natural and cultivated), were initially considered separately. In an
attempt to isolate the forested areas from the natural vegetation, masks derived
through image classification were used to differentially enhance the various
features.
Results indicate that the use of any particular method to the exclusion of all
others will seriously limit the scope of conclusions possible through interpretation
of the information present. Enhancement of information in one domain will
inadvertently lead to the suppression of information from one or more of the coexisting
domains. A series of results from a sequence of procedures interpreted
in parallel will in every case produce information of a higher decision making
quality. / AC2017
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The petrology, geochemistry and classification of the Bien Venue massive sulphide deposit, Barberton mountain land.Murphy, Philip William. January 1990 (has links)
The Bien Venue massive sulphide deposit is associated with a felsic volcanic succession
developed in the north-eastern part of the Barberton Greenstone Belt, Eastern Transvaal. The
deposit is situated 8km east-north-east of Louw's Creek between the Lily Syncline to the south
and the Stentor Pluton to the north. The stratigraphy of the Onverwacht, Fig Tree and
Moodies Groups in the vicinity of the deposit is poorly documented, and the exact stratigraphic
position of the host felsic volcanics is not known. They are tentatively correlated with the felsic
volcanics from the Theespruit Formation, Onverwacht Group.
The felsic volcanics have undergone low-grade greenschist facies metamorphism and occur as
quartz-sericite schists. Detailed petrography enables sub-division of the volcanic succession into
distinct units. A lapilli metatuff unit hosts the base metal and precious metal mineralisation.
The sulphides are best developed in the upper part of this unit, together with intercalated
barite-rich horizons and cherts. A series of structural events have modified the attitude of the
lithological units and disrupted the continuity of the orebody.
The orebody comprises stratabound lenses of massive to semi-massive and often banded
sulphides, as well as disseminated sulphide mineralisation. The dominant base metal mineralogy
consists of pyrite, sphalerite, chalcopyrite, galena and tennantite. Native silver and various
copper-silver sulphides are also associated with the base metal sulphides. A vertical zonation
of the mineralisation exists, from pyrite-chalcopyrite-rich ore in the footwall, to pyrite -
chalcopyrite-sphalerite-galena-barite-rich ore towards the hanging wall.
Geochemical studies indicate that the Bien Venue lithologies are rhyolitic to rhyodacitic in
composition and show a calc-alkaline affinity. The mobility of some elements at Bien Venue
has been clearly demonstrated. This is believed to be associated with hydrothermal alteration
that has led to SiO2 and MgO enrichment, as well as K2O depletion, in the wall rocks of the
deposit.
The geological setting and nature of the mineralisation at Bien Venue suggest that it is an
example of a volcanogenic exhalative sulphide deposit. In terms of the classification scheme
suggested by Hutchinson (1973, 1980), Bien Venue would best be described as a Primitive type
deposit that contains barite. / Thesis (M.Sc.)-University of Natal, 1990
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The geology and geochemistry of the Sterkspruit intrusion, Barberton Mountain Land, Mpumalanga provinceConway, Gavin, Patrick January 1997 (has links)
Thesis (M.Sc.)--University of the Witwatersrand, Science Faculty (Geology), 1997. / The Sterkspruit Intrusion, in the south-western portion of the Barberton
greenstone belt, is a sill-like body containing rocks of gabbroic to dioritic
composition. It is hosted by a sequence of komatiitic basalts and komatiites of
the Lower Onverwacht Group. The intrusion is considered unique in this area in
that it lacks ultramafic components and has no affinities with the surrounding
mafic- to- ultramafic lavas. The gabbroic suite also contains an unusual
abundance of quartz, and the chill margin shows an evolved quartz-normative,
tholeiitic parental magma. Based on petrographic and geochemical evidence,
the intrusion can be subdivided into four gabbroic zones and a quartz diorite,
which is an end product of a differentiating magma. The chill margin records an
MgO content of 4.8%, an Mg# of 42, an Si02 value of 52.5% and a normative
plagioclase composition of An44. The sill-like nature of the body, indicated by
geochemical trends, and the steep sub-vertical layering, point to a body that
has been tilted along with the surrounding lavas. This constrains the relative
age of the body to be older than the emplacement of the Kaap Valley and
Nelshoogte Plutons, which caused the regional deformation observed in the
Nelshoogte Schist Belt. A sequence of tholeiitic to andesitic basalts from the
Kromberg Formation in the Upper Onverwacht Group, have compositions which
can be correlated with the Sterkspruit Intrusion. It is possible that this body
represents a subvolcanic magma chamber, which acted as a feeder to tholeiitic
lavas higher up in the volcanic sequence. The Sterkspruit Mafic Dyke Swarm
intruded the southern Nelshoogte Schist Belt and displays intra-dyke chemical
variation. / AC2017
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The geology and geochemistry of the Sterkspruit intrusion, Barberton Mountain Land, Mpumalanga province.Conway, Gavin Patrick. January 1997 (has links)
A dissertation submitted to the Faculty of Science, University of the
Witwatersrand, Johannesburg, in fulfilment of the requirements for the
degree of Master of Science. / The Sterkspruit Intrusion, in the south-western portion of the Barberton
greenstone belt, is a sill-like body containing rocks of gabbroic to dioritic
composition, It is hosted by a sequence of komatilitic basalts and komatilites of
the Lower Onverwacht Group. The intrusion is considered unique in this area in
that it lacks ultramafic components and has no affinities with the surrounding
mafic- to- ultramafic lavas, The gabbroic suite also contains an unusual
abundance of quartz, and the chill margin shows an evolved quartz-normative,
tholelitic parental magma. ( Abbreviation abstract ) / AC2017
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The geology of the lily syncline and portion of the eureka syncline between the consort mine and Joe's Lucic siding, Barberton mountain land.Viljoen, Morris James January 1963 (has links)
Thesis submitted for the degree of Master of Science in the Faculty of Science, University of the Witwaiersrand, Johannesburg. / The following is an account of the stiatigiaphy, structure, metamorphism and mineralization in a complexly deformed area of the northwest part of the Barberton Mountain Land. It is situated at the eastern extremity of the Jamestown Hills and covets a region along the contact zone between the ancient layered rocks of the Archaean Complex and the Nelspruit Granite.
In the first section is given a fairly comprehensive account of previous work done in the Barberton region- especially as it applies to the area under discussion. This is followed by a consideration of the petrology and stratigraphy of the area and a description of the various structures encountered. A more detailed statistical treatment of the minor structures is also included and from these results an attempt is made to unravel the tectonic history of the area and to fit it into the regional structural pattern of the Mountain Land as a whole.
The area mapped consists of two basically Identical successions separated by a major high angled thrust fault. The northern succession, which has been quite strongly thermally metamorphosed, represents the fairly steeply south dipping northern limb of the Lily Syncline. That to the south has suffered very little metamorphism and forms part of the northern limb of the Eureka Syncline.
A well developed and layered basic suite of rocks lying below the Fig-tree Series .and constituting the basal zone of the Lily Syncline, is classed in the Onverwacht Series, It lies in direct contact with the Nelspruit Granite and is considered to represent a metamorphosed succession of impure dolomites with arenaceous and minor shaly horizons, together probably with some basic and acid lavas. The Onverwacht rocks are overlain by metamorphosed Fig-tree shales and "lavas", and these in turn by metamorphosed conglomerates and quartzites of the Moodies System. At the base of the homfelses lies the Consort "Contact" or Consort "Bar", a siUcified, mineralized zone which is the main ore horizon of the Consort Mine. The homfelses grade into rocks which have been termed "lavas" but which are thought to be mote of the nature of crystalline tuffs.
The succession to the south of the Main Fault Is on a broad scale Identical to the one just described above, differing mainly in metamorplilc state. Thus, whereas the Onverwacht rocks of the northern succession have been converted to hornblende and tremolite-actinollte schists, similar rocks to the south of the Main Fault have been changed to carbonate-bearing talc and chlorite phylUtes.
The basic Intrusive rocks of the Jamestown are considered to be of a much smaller distribution than was previously thought,and are represented mainly by the massive bodies of pure serpentinite. There is a possibility however; that certain of the purer talc- carbonate schists along the Kaap Rivet,represent altered ultrabasic intmsives.
The Nelspruit gneiss and migmatlte is considered to represent a completely granitized pre-Swaziland System sequence which at a much later date acted as the basement upon which the layered rocks of the Mountain Land were deposited, A re-moblllzed border phase of this migmatite was largely responsible for the contact metamorphism around the edge of the Mountain Land and late hydrothermal solutions from this same intrusive granite resulted in the mineralization of the area. The isolated patches of black amphibolites situated well within the granite outcrop area, are considered to be isolated downfolded remnants of a once mote extensive sheet of Onverwacht. Their high grade metamorphic state, as with the Onverwacht rocks along the immediate contact zone. Is due to the effects of the Intrusive granites plus the re-heaied migmatite.
Three distinct facies of contact metamorphism (related to the Nelspruit Granite) ate recognised in the area.
The area can be divided into three fairly distinct structural zones, each one characterized by the good development (as compared to the other zones) of one or mote particular types or styles of deformation. Thus in the Consort Mine area (Zone I), a northwest-trending fold system is the strongest and most apparent structural feature. In the southern part of the area (Zone U), minor ctenulation and conjugate folds are very well developed. In the rocks along the granite contact zone (Zone IH), a metamorphic fabric and well/developed lineations associated with strong shearing, are the most noteworthy structural features. ’
Special attention was devoted to the accurate observation and recording of minor structural features. As a result of this, 4 distinct phases of deformation, corresponding fairly closely to those described by Ramsay (1963), were recognised. The first resulted in strong folding about northeast-trending axes and caused the formation of the major synclines
(Including the Eureka and Lily Synclines) and the major faults (Including the Lily, Main Southern and Woodstock Faults). The first period was followed by the widespread development of cleavage, associated with which is the marked flattening and elongation of conglomerate pebbles,and development of various types of lineations including the alignment of metamotphic minerals along the immediate contact belt. Certain of the lineations appear to have formed mainly after crystallization of the granite, and are closely connected with the mechanical deformation (in the form of strong differential shearing) which affected the rocks along the contact. At a late stage during the 2nd period, hydrothermal solutions from the granites entered zones of strong shearing and structural disturbance which had started to develop in the layered rocks. The initial development of the 3rd fold stmctures (especially in the northwest part of the Mountain Land) is considered to have played an important part In the localization of these ore fluids.
Both the 1st. and 2nd formed stmctures have been strongly deformed by a northwest-trending fold system. These 3rd phase folds teach their best development in the Consort Mine area where they constitute by far the strongest stmctural feature. This period of folding,which during the very early stages probably played a part in the localisation of the ore fluids, outlasted the mineralizing episode and in the Consort Mine area, strongly deformed the mineralized "Contact”. The marked inflection in the northwest part of the Mountain Land, including the "bending" of the Eureka and Ulundi Synclines, occuned at this stage.
Most of the major faults truncate the 3rd folds and are thought to have formed, or to have been rejuvenated,at a late stage during this period of deformation.
The 4th and final phase of deformation is represented by the fairly widespread development of minor crenulation and conjugate folds. Their development is largely controlled by the rock types and they only occur in lithologically favourable varieties. The maximum deforming stress which caused these folds must have been nearly vertical. These 4th structures are completely separate and unrelated to the main northwest-trending fold system (3rd structures) with which they were classed by Ramsay (1963),
From an economic point of view, three zones of potential mineralization, corresponding in all cases to zones of strong shearing and stmcmral disturbance, occur in the area. The most Important is the silicified and mineralized zone (within the northern limb of the Lily Syncline) between basic schists of the Onverwacht and the overlying Fig-tree homfelses, known as the Consort "Contact" or Consort "Bar". Another potential zone of
mineralization is the westward extension of the so-called Lily Fault which occupies exactly the same stratigraphic position as the Consort "Contact", viz. between shales and basic rocks of the Flg-uee and Onverwacht Series respectively, but within the northern limb of the Eureka Syncline. Finally, certain shaly horizons within the "footwall" quartzitic layers of the Consort Mine area also show signs of weak mineralization. / AC 2018
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The geology of the lily syncline and portion of the eureka syncline between the consort mine and Joe's lucic siding, Barberton mountain landVILJOEN, Morris, James January 1963 (has links)
Thesis submitted for the degree of Master of Science
in the Faculty of Science, University of the Witwatersrand,
Johannesburg. / The following is an account of the stiatigiaphy, structure, metamorphism
and mineralization in a complexly deformed area of the northwest part of the Barberton
Mountain Land. It is situated at the eastern extremity of the Jamestown Hills and covets
a region along the contact zone between the ancient layered rocks of the Archaean Complex
and the Nelspruit Granite.
In the first section is given a fairly comprehensive account of previous work
done in the Barberton region- especially as it applies to the area under discussion. This is
followed by a consideration of the petrology and stratigraphy of the area and a description
of the various structures encountered. A more detailed statistical treatment of the minor
structures is also included and from these results an attempt is made to unravel the tectonic
history of the area and to fit it into the regional structural pattern of the Mountain Land as
a whole.
The area mapped consists of two basically Identical successions separated
by a major high angled thrust fault. The northern succession, which has been quite strongly
thermally metamorphosed, represents the fairly steeply south dipping northern limb of the
Lily Syncline. That to the south has suffered very little metamorphism and forms part of
the northern limb of the Eureka Syncline.
A well developed and layered basic suite of rocks lying below the Fig-tree
Series .and constituting the basal zone of the Lily Syncline, is classed in the Onverwacht
Series, It lies in direct contact with the Nelspruit Granite and is considered to represent a
metamorphosed succession of impure dolomites with arenaceous and minor shaly horizons,
together probably with some basic and acid lavas. The Onverwacht rocks are overlain by
metamorphosed Fig-tree shales and "lavas", and these in turn by metamorphosed conglomerates
and quartzites of the Moodies System. At the base of the homfelses lies the Consort "Contact"
or Consort "Bar", a siUcified, mineralized zone which is the main ore horizon of the Consort
Mine. The homfelses grade into rocks which have been termed "lavas" but which are thought
to be mote of the nature of crystalline tuffs.
The succession to the south of the Main Fault Is on a broad scale Identical
to the one just described above, differing mainly in metamorplilc state. Thus, whereas
the Onverwacht rocks of the northern succession have been converted to hornblende and
tremolite-actinollte schists, similar rocks to the south of the Main Fault have been changed
to carbonate-bearing talc and chlorite phylUtes.
The basic Intrusive rocks of the Jamestown are considered to be of a much
smaller distribution than was previously thought,and are represented mainly by the massive
bodies of pure serpentinite. There is a possibility however; that certain of the purer talccarbonate
schists along the Kaap Rivet,represent altered ultrabasic intmsives.
The Nelspruit gneiss and migmatlte is considered to represent a completely
granitized pre-Swaziland System sequence which at a much later date acted as the basement
upon which the layered rocks of the Mountain Land were deposited, A re-moblllzed border
phase of this migmatite was largely responsible for the contact metamorphism around the
edge of the Mountain Land and late hydrothermal solutions from this same intrusive granite
resulted in the mineralization of the area. The isolated patches of black amphibolites
situated well within the granite outcrop area, are considered to be isolated downfolded
remnants of a once mote extensive sheet of Onverwacht. Their high grade metamorphic
state, as with the Onverwacht rocks along the immediate contact zone. Is due to the
effects of the Intrusive granites plus the re-heaied migmatite.
Three distinct facies of contact metamorphism (related to the Nelspruit
Granite) ate recognised in the area.
The area can be divided into three fairly distinct structural zones, each one
characterized by the good development (as compared to the other zones) of one or mote
particular types or styles of deformation. Thus in the Consort Mine area (Zone I), a northwest-
trending fold system is the strongest and most apparent structural feature. In the
southern part of the area (Zone U), minor ctenulation and conjugate folds are very well
developed. In the rocks along the granite contact zone (Zone IH), a metamorphic fabric
and well/developed lineations associated with strong shearing, are the most noteworthy
structural features. ’
Special attention was devoted to the accurate observation and recording of
minor structural features. As a result of this, 4 distinct phases of deformation, corresponding
fairly closely to those described by Ramsay (1963), were recognised. The first resulted in
strong folding about northeast-trending axes and caused the formation of the major synclines
(Including the Eureka and Lily Synclines) and the major faults (Including the Lily, Main
Southern and Woodstock Faults). The first period was followed by the widespread development
of cleavage, associated with which is the marked flattening and elongation of conglomerate
pebbles,and development of various types of lineations including the alignment of metamotphic
minerals along the immediate contact belt. Certain of the lineations appear to have formed
mainly after crystallization of the granite, and are closely connected with the mechanical
deformation (in the form of strong differential shearing) which affected the rocks along the
contact. At a late stage during the 2nd period, hydrothermal solutions from the granites
entered zones of strong shearing and structural disturbance which had started to develop in the
layered rocks. The initial development of the 3rd fold stmctures (especially in the northwest
part of the Mountain Land) is considered to have played an important part In the localization
of these ore fluids.
Both the 1st. and 2nd formed stmctures have been strongly deformed by a northwest-trending fold system. These 3rd phase folds teach their best development in the Consort Mine area where they constitute by far the strongest stmctural feature. This period of folding,which during the very early stages probably played a part in the localisation of the ore fluids, outlasted the mineralizing episode and in the Consort Mine area, strongly deformed the mineralized "Contact”. The marked inflection in the northwest part of the Mountain Land, including the "bending" of the Eureka and Ulundi Synclines, occuned at this stage.
Most of the major faults truncate the 3rd folds and are thought to have formed, or to have been rejuvenated,at a late stage during this period of deformation.
The 4th and final phase of deformation is represented by the fairly widespread development of minor crenulation and conjugate folds. Their development is largely controlled by the rock types and they only occur in lithologically favourable varieties. The maximum deforming stress which caused these folds must have been nearly vertical. These 4th structures are completely separate and unrelated to the main northwest-trending fold system (3rd structures) with which they were classed by Ramsay (1963),
From an economic point of view, three zones of potential mineralization, corresponding in all cases to zones of strong shearing and stuctural disturbance, occur in the area. The most Important is the silicified and mineralized zone (within the northern limb of the Lily Syncline) between basic schists of the Onverwacht and the overlying Fig-tree homfelses, known as the Consort "Contact" or Consort "Bar". Another potential zone of
mineralization is the westward extension of the so-called Lily Fault which occupies exactly
the same stratigraphic position as the Consort "Contact", viz. between shales and basic
rocks of the Flg-uee and Onverwacht Series respectively, but within the northern limb of
the Eureka Syncline. Finally, certain shaly horizons within the "footwall" quartzitic
layers of the Consort Mine area also show signs of weak mineralization. / AC 2018
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Aspects of volcanism and metamorphism of the Onverwacht group lavas in the South-Western portion of the Barberton greenstone belt.Cloete, Marthinus January 1994 (has links)
A Dissertation Submitted to the Faculty of Science;
University of the Witwatersrand, Johannesburg; for
the Degree of Doctor of Philosophy / A volcanological study of the Onverwacht Group in the southwestern part of the
Archaean (-3.5 - 3.2 Ga) Barberton greenstone belt (BGB), South Africa, shows that
volcanic extrusion rates of the Komati and Hooggenoeg Formations must have been high
to have maintained the degree of submarine sheet flooding that is evident. It is
concluded that the volcanic attributes of the Komati and Hooggenoeg Formations are
not typical of MOR crust, as has been claimed, but rather closely resemble those of
modern oceanic plateaus. The shear-zone-bound basal contact of the Komati Formation
suggests that the top of the ancient oceanic plateau was allochthonously emplaced and
delaminated from its basal (intrusive) part. (Abbreviation abstract) / AC2017
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The geology of the Lily Syncline and portion of the Eureka Syncline between Sheba Siding and Louw's Creek Station, Barberton Mountain LandAnhaeusser, C R (Carl Robert) 16 September 2014 (has links)
No description available.
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Evaluating image classification techniques on ASTER data for lithological discrimination in the Barberton Greenstone Belt, Mpumalanga, South AfricaKemp, Jacobus Nicholas, Zietsman, H. L., Stevens, G. 12 1900 (has links)
Thesis (MSc (Geography and Environmental Studies))--University of Stellenbosch, 2005. / 81 Leaves printed on single pages i-xi, preliminary pages and numbered pages 1- 70. Includes bibliography, list of tables and list of figures. / Digitized at 300 dpi color PDF format (OCR), using KODAK i 1220 PLUS scanner. / ENGLISH ABSTRACT: Geological field mapping is often limited by logistical and cost constraints as well as the
scope and extent of observations possible using ground-based mapping. Remote sensing
offers, among others, the advantages of an increased spectral range for observations and a
regional perspective of areas under observation. This study aimed to determine the accuracy
of a collection of image classification techniques when applied to ASTER reflectance data.
Band rationing, the Crosta Technique, Constrained Energy Minimization, Spectral Correlation
Mapping and the Maximum Likelihood Classifier were evaluated for their efficiency in
detecting and discriminating between greenstone and granitoid material. The study area was
the Archaean Barberton Greenstone Belt in the eastern Mpumalanga Province, South Africa.
ASTER reflectance imagery was acquired and pre-processed. Training and reference data was
extracted from the image through visual inspection and expert knowledge. The training data
was used in conjunction with USGS mineral spectra to train the five classification algorithms
using the ERDAS's software package. This resulted in abundance images for the target
materials specified by the training data. The Maximum Likelihood Classifier produced a
classified thematic map. The reference data was used to perform a rigorous classification
accuracy assessment procedure. All abundance images were thresholded to varying levels,
obtaining accuracy statistics at every level. In so doing, threshold levels could be defined for
every abundance image in such a way that the reliability of the classification was optimized.
For each abundance image, as well as for the output map of the Maximum Likelihood
Classifier, user's- and producer's accuracies as well as kappa statistics were derived and used
as comparative measures of efficiency between the five techniques. This information was also
used to assess the spectral separability of the target materials.
The Maximum Likelihood Classifier outperformed the other techniques significantly,
achieving an overall classification accuracy of 81.1% and an overall kappa value of 0.748.
Greenstone rocks were accurately discriminated from granitoid rocks with accuracies between
72.9% and 98.5%, while granitoid rocks showed very poor ability to be accurately
distinguished from each other.
The main recommendations from this study are that thermal infrared and gamma-ray data be
considered, together with better vegetation masking and an investigation into object orientated
techniques. / AFRIKAANSE OPSOMMING: Geologiese veldkartering word algemeen beperk deur logistiese en koste-verwante faktore,
sowel as die beperkte bestek waartoe waarnemings met veld-gebasseerde tegnieke gemaak
kan word. Afstandswaarneming bied, onder andere, 'n vergrote spekrale omvang vir
waarnemings en 'n regionale perspektief van die area wat bestudeer word. Hierdie studie was
gemik daarop om die akkuraatheid van 'n versameling beeld-klassifikasie tegnieke, toegepas
op ASTER data, te bepaal. Bandverhoudings, die Crosta Tegniek, "Constrained Energy
Minimization", Spektrale Korrellasie Kartering, en Maksimum Waarskynlikheid Klassifikasie
is evalueer op grond van hul vermoë om groensteen en granitoied-rotse op te spoor en tussen
hulle te onderskei. Die studiegebied was die Argalese Barberton Groensteengordel in die
oostelike Mpumalanga Provinsie in Suid Afrika.
'n ASTER refleksie beeld is verkry, waarop voorverwerking uitgevoer is. Opleidings- en
verwysingsdata is van die beeld verkry deur visuele inspeksie en vakkundige kennis. Die
opleidingsdata is saam met VSGO mineraalspektra gebruik om die vyf klassifikasie
algoritmes met behulp van die ERDAS sagteware pakket op te lei. Die resultaat was
volopheidsbeelde vir die teikenmateriale gespesifiseer in die opleidingsdata. Die Maksimum
Waarskynlikheid algoritme het 'n geklassifiseerde tematiese beeld gelewer. Met behulp van
die verwysingsdata is 'n streng akkuraatheidstoetsing prosedure uitgevoer. Vir alle
volopheidsbeelde is 'n reeks drempelwaardes gestel, en by elke drempelwaarde is
akkuraatheidsstatistieke afgelei. Op hierdie manier kon 'n drempelwaarde vir elke
volopheidsbeeld vasgestel word sodat die drempelwaarde die betroubaarheid van die
klassifikasie optimeer. Vir elke volopheidsbeeld, asook vir die tematiese kaart verkry van die
Maksimum Waarskynlikheid klassifikasie, is gebruikers- en produsent-akkuraathede en kappa
statistieke bereken. Hierdie waardes is gebruik as vergelykende maatstawwe van akkuraatheid
tussen die vyf tegnieke, asook van die spektrale skeibaarheid van die onderskeie
teikenmateriale.
Die Maksimum Waarskynlikheid klassifikasie het die beste resultate gelewer, met 'n algehele
klassifikasie akkuraatheid van 81.1%, en 'n gemiddelde kappa waarde van 0.748.
Groensteenrotse kon met hoë akkuraathede van tussen 72.9% en 98.5% van granitoiedrotse
onderskei word, terwyl granitoiedrotse 'n swak vermoë getoon het om van mekaar onderskei
te word. Die belangrikste aanbevelings vanuit hierdie studie is dat termiese uitstralingdata asook
gamma-straal data geimplimenteer word. Beter verwydering van plantegroei en 'n studie na
die lewensvatbaarheid van objekgeorienteerde metodes word ook aanbeveel.
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