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REPORT FROM NATIONAL WORKING GROUPS
OF IGCP 299 IN 1992
REPORT FROM THE BRITISH GROUP
M. M. Sweeting ( U.K.)
The work of the British Group during 1991-1992 has progressed slowly , but
several works have been completed.
At Wallingford (Institute of Geological Sciences ,Hydrological Group)and at Reading
University , Dr. Mike Price and Dr. R. Downing had completed the editing of a work on the
chalk , and its hydrogeology.
In Oxford , Prof.Goudie and Dr.Viles have published work on the tufa deposits of the
Kimberley region , Australia. Prof. Goudie has also studied the inter-relations of the
landforms in the Kimberley area with the variations of the Devonian limestones , Both
Goudie and Viles have a joint program with the University of Tubingen , Germany on tufa
deposition and formation in the Cotswalds of England and the Swabian Alps of Germany , Dr.
Bull has continued his work on the cave sediments of the Guilin and Laibin areas , in
Guangxi , China . Dr. Sweeting has continued her Monograph on karst Geomorphology in China
, which is nearly complete.
In Northern England , Dr. Helen Goldie has continued her work on limestone pavements and
the problems associated with their preservation .Her work has been published in a volume
on the human use of karstic terrains , and published by the International Geographical
Union (I.G.U.). Dr. Peter Smart working in Bristol , has published on methods of dating in
karst. This has been produced by the British Geomorphological Research Group(1991).
Dr.Tony Waltham and his fellow speleologists visited Xingwen ( Sichuan)and Tibet this year
.Their projects also form part of the British contribution to IGCP 299. In Manchester ,
Zhang Dian ( from Nanjing) has completed a long ph.D. thesis on Tibet , under the guidance
of Prof. Ian Douglas.
We have provisionally booked rooms in Oxford for a meeting of IGCP 299 be held in 1994.
Details will be given next year, but we hope there will be a field trip -- either to south
Wales or to Northern England. It is likely to be held in September 1994.
PLAN OF THE CZECHOSLOVAK WORKING GROUP
Dr. Vojen Lozek (Czech and Slovak Republic)
The work of the Czechoslovak working group is centered on the correlation
of climatic changes with karst processes during the Late Tertiary and Quaternary.
Attention will most frequently be concentrated on the following problems and processes:
- Karst processes during the course of the climatic cycle reflected by changes in
sedimentation, soil formation, CaCO3 dissolution or precipitation as well as by
the sequences of faunal assemblages/Mollusca,Vertebrata/Sedimentation and pedogenesis in
correlation with ecosystem development/vegetational and faunal succession/
- Correlation of various kinds of sediments with included molluscan and vertebrate fossils
Zoostratigraphy of karst sediments, particularly of cave and rock-shelter fills
- Depositional and erosional processes in time and space Climatically important sediments
in relation to karstification:
Loess formation indicating cold-dry intervals corresponding to stillstand phases both in
karstification and clastic slope deposition/screes/. Drying up of caves.
Tufa and sinter formation indicating moist and mostly also warm intervals largely
corresponding to stillstand phases in slope clasftic deposition, but reflecting an
intensive dissolution and precipitation of CaCO3 , i.e., a strong
karstification and soil formation/terrae/.
- Decalcification of surface soils, foam sinter formation in caves and rock-shelters.
Evidence for humid phases associated with maximum intensity of karst processes. Early
Atlantic period as Holocene moisture maximum
- Mutual relation of clastic and chemical sedimentation pure tufa deposits situated in
footslope position documenting stillstand phases in the deposition of clastic slope
material: scree interlayers within tufa sequences reflection interruptions in CaCO3
precipitation and thus corresponding to phases with increased movement of slope material
.Oscillation in the karst water regime: Subboreal sensu K. - D.Jager/1969/ as Holocene
moisture minimum.
- Correlation between environmental changes and human activities
Deforestation of karstlands , soil erosion and formation of bare lapies fields
Developmental history of open/i.e. deforested/karstlands
- Importance of depositional sequences in the karstlands to the knowledge of the
Quaternary/and Late Tertiary/:
Dating the decline of loess formation
Recording humid and dry phases of the Late Tertiary-Quaternary climatic cycle in various
altitudinal zones
Documenting phases of maximum and minimum scree formation.
Impact of changes in biocoenoses on the karst landscape/deforestation/correlation between
human activities and various natural processes/man-made erosion and soil destruction etc./
- Overall reconstruction of landscape development in karstland environments
KARST MAP OF FORMER USSR
G.N.Dyblyanskaya (Simferopol , Ukraine)
V.N.Dyblyansky(Simferopol ,Ukraine)
K.A.Gorbunova (Perm , Russia)
A.B.Klimchouk (Kiev , Ukraine)
The map series is compiled by 23 karstologists from 18 institutions in the
former USSR. It is originally in the scale of 1:2,500,000 , and has 16 sheets altogether
.The series consist of three maps , i.e., map of karst lithologic types(fig.1); map of
karst types(fig.2); and a map of tectonics division by Yershov. A reduction version in the
scale of 1:25,000,000 was prepared as a contribution to IGCP 299.
Fig.1 , Karst Lithologic Types in
the Territory of Former USSR.
(by G.N.Dyblyanskaya and V.N.Dyblyansky)
Karst Lithologic Types:1 , limestone; 2 , chalk and dolomite;3 ,
sulfates(gypsum and anhydrite); 4 , rock salt (sodium and potassium salt); 5 ,limestone
and dolomite mixture; 6 ,carbonate- sulfate mixture(limestone , dolomite ,gypsum
,anhydrite); 7 ,terrigenous carbonate (alternation of Limestone , dolomite , marl ,
siltstone , sandstone , argillaceous , and clay beds); 8 , terrigenous sulfates
(alternation of gypsum , anhydrite , siltstone ,sandstone , argillaceous , and clay beds);
9 , intercalation of karstified layer in non-soluble strata (intercalation of limestone ,
dolomite in siltstone ,sandstone , siltstone , and clay).
Boundaries: 10 ,between different types of karstified rocks;11 , small areas of karstified
rock , can not be shown as limited by the scale of map (basically carbonate rock); 12 ,
non-soluble rock area.
Fig.2 Karst types according to the
characteristics of covering rocks
on the karstified strata.(by G.N.Dyblyanskaya , and V.N.Dyblyansky).
Karst types: 1 , Bare karst: in remarkable area (left); in area less than
100 km2 (right); 2 ,covered karst , karstified strata covered by loose
sendiments more than 2m thick; 3 , buried karst , karstified strata buried under
nonsoluble bedrock , in remarkable area (left) , in area less than 100 km2(right);4
,covered-buried kars ,karstified strata underlying both loose sediments and nonsoluble
bedrock.
Boundaries: 5 , between karst types; 6 , southern limit of permafrost; 7 , line of maximum
Quaternary Deposit ; 8 , Non-soluble rock area.
(Translated from Russian by Yuan Daoxian)
KARST AND CAVES IN CANADA
Derek C.Ford (Canada)
The Hungarian working of IGCP 299 Project (Geology.Climate , Hydrology and
Karst Formation) continues his karst documentation program creating a world-wide karst
data-base. To this program we have received important numerical data of Canadian karst
from Prof. Derek C. Ford , McMaster University , Hamilton , Ontario.
According to D.C.Ford the extension of naked (bare)carbonate karst outcrop in Canada is
900 ,000 km2 , the covered karst about 100,000 km2. The approximate
number of known caves in carbonate rocks is 500 , with a total length of 100 km. Area of
gypsum karst is 80,000 km2 , number of surveyed caves 50 , total length 20 km.
(The most important Canadian karst areas are listed on Fig.1.
Fig.1 Karst areas of Canada (after
D.C. ford)
A= larger outcrops of limestone
,dolomite and gyp
B= subcrop of salt ,C= line of
permafrost.
The main karst areas: 1. Anticosti Island ,
Quebec ,
2. Niagara Scarp , Ontario 3.Rocky
Mountains ,
4. Vancouver Island , 5. Mackenzie Mountains ,
NW Territories ,
6. Interlakes ,Manitoba ,7.Hudson Bay Lowland
,8. Victoria Island, NW Territories.
The distribution of karst areas in Canada are shown in Fig.1. All common limestone and
dolomite facies are found except chalk .Marble , gypsum ,and anhydrite are also abundant.
The age range is from Archean to Jurassic karst rocks outcrop in every major geologic
,tectonic , topographic , and climatic region of the country. More than 90 percent of the
outcrop was ice-covered during the last( Late Wisconsinan ) glaciation , glacier recession
occurred between approximately 15,000 and 7,000 y. B.P. .In the northwest , some karst
areas have escaped the last several glaciations (e.g., Nahanni karst in Mackenzie
Mountains) and there are others that appear never to have been glaciated; however , they
will have been very cold and dry during glacial stages.
Approximately 50 per cent of the outcrop of karst rocks in Canada is technically
permafrozen (see line of permafrost , fig.1.).A model for the relationship between
permafrost and karst development in the Mackenzie Mountains (Lat.62-63°N) is given in
Fig.2 .There are three distinct hydrologic zones. A high zone of ancient caves and
sinkholes is perm afrozen and inert.
Fig.2 Model for karst and permafrost zonation in rugged terrain
where perma-frost is widespread but discontinous(after D.C. Ford ,based on examples in the
Mackenzie Mts.). I.= complete permafrost , II.= a periodic impedance of drainage ,
III.= unimpeded drainage. nk= non karstic caprock , c= cenote type doline ,p= permanent
ice seal , t= temporary ice seal, s= standing water.
A low zone represented by poljes and the bases of large sinkholes and
solution corridors is the focus of local and allogenic runoff and displays unimpeded
drainage to the aquifers ,i. e. , no permafrost. In an intermediate zone there is
a-periodic impedance of karst recharge: ice seals form in the bottoms of the input
features such as dolines , then over one or a few consecutive melt seasons water
accumulates above the seals until the hydrostatic pressure is sufficient to rupture them;
they drain in the space of a few hours or days. This behavior tends to create cenote-form
dolines.
REPORT OF THE HUNGARIAN WORKING GROUP
D. Balazs (Hungary)
First team: hydrothermal karst correlation programme /3 members/
Team leader: K.Takacs-Bolner
Achievements in 1992:
- Beside of field work carried out in Hungarian caves /Buda Mts., Pilis Mts.,
Miskolctapolca and Beremend/ two members of the team took part in a one-month field
symposium studying Jewel Cave and Wind Cave , the largest cave systems of thermal water
origin , South Dakota and other caves of phreatic origin in Kentucky and New Mexico ,US
,by invitation of McMaster University , Hamilton , Canada.
- Stable isotope and cathode luminescence analyses were carried out on samples of
carbonatic speleothems from Buda caves in Oxford University , and further stable isotope
and fluid inclusion analyses are in progress at McMaster University ,Canada and at
Institute of Geology and Geophysics , Novosibirsk ,Russia. Dozen of thin sections were
prepared for detailed microscopic studies.
- One member of the team took part in the European Regional Conference of UIS , Belgium ,
and presented a lecture "Paleokarst and long termed karst evolution of Buda Mts.,
Hungary". Her Ph. D. thesis has been completed with the same title. The members of
the team have published two papers on the first results of the laboratory analyses.
Second team: karst documentation programme /4 members/
Team leader: D. Balazs
Achievements in 1992:
- The team continued the systematic collection of karst from all over the world by help of
a unified formular. The main purpose of this work is to create a global data-base on karst
areas and to publish the Karst Atlas of the World .This project is supported by the
Hungarian Speleological Society ,but the fulfillment of this programme is handicapped by
financial problems .
- Two members of subgroup participated in the European Regional Conference presenting a
lecture , and before and after the conference they took part in a European study tour
visiting many caves and karst areas in Belgium , Germany and Austria.
- The members of the team published more short preliminary reports on karst documentation
programme and a detailed study on the global correlation of karst depressions /doline
types and doline complexes/.
TYPICAL KARST AREA-SKOCJANSKE JAME (SLOVENIA ,
May , 1992)
Andrej KRANJC (National Coordinator)
1. INTRODUCTION
According to program and plan for 1991 we investigated ,studied respectively the
following topics in the area of Skocjanske Jame Karst:
- new survey of Hanke's Channel and history of Skocjanske jame investigations (A. Mihevc
& A. Kranjc)
- lithostratigraphy and paleoecology of Skocjanske jame Karst (Geological investigations)
(M. Knez)
- connection of fissured zones with underground channels (Tectonical investigations) (S.
Sebela)
- flowstone datings (N. Zupan)
- chemical characteristics of percolated water (J.Kogovsek)
- flowstone deposition (J. Kogovsek , A. Kranjc , S. Sebela)
- erosion and corrosion measurements in the active part of Skocjanske jame (A.Mihevc)
- rocky features (T. Slabe)
2. SHORT DESCRIPTION OF ACHIEVED WORK AND PRELIMINARY RESULTS
2.1 New survey of Hanke's Channel and history of Skocjanske jame
investigations
In order to achieve the foreseen researches, to locate the researches
respectively , the detailed survey of the Hanke's channel was necessary. This is the
biggest active water channel in Skocjanske jame and the existing surveys (from the end of
the last century) , the plan respectively did not meet the modern requirements.
In 1991 the lower part of the cave was surveyed. Morphologically it is 80 to 90m deep , in
average 15m wide underground canyon which widens in front of the final siphon into
Martel's Chamber. The chamber is 220m long ,150 m wide and up to 130 m high.
The review of older sources on investigation , exploration and survey of Skocjanske jame ,
of the Hanke's channel in particular, with a special accent given to the names of
particular parts of the cave and to the single details.Due to the fact that the cave
belonged during the first explorations to Austro-Hungarian Monarchy , later to Italy , to
Yugoslavia and Slovenia at last the names accordingly changed during the time. Connected
to the history of explorations A.Kranjc visited in 1991 the Museum in Salzburg and the
Speleological Institute in Vienna to look over the archives.
2.2 Lithostratigraphy and paleoecology of Skocjanske jame karst (Geological
investigations)
Mostly carbonate sediments, occurring in SW Slovenia and Istria among the rudist
limestones and limestones with alveolines and nummulites are called Liburnian formations.
Now the lower part of Liburnian formation is called Vreme Beds, they are of Maastrichtian
age (upper part of the Upper Cretaceous) , the medium part are Kozina Beds of Danian age
and the upper part is built by milliolid limestones of Thanetian age.
In the vicinity of Skocjanske jame where among the others, the beds of Liburnian formation
appear ,three profiles were treated from the stratigraphic paleoecological point of
view:Vremski Britof (Maastrichtian), Divaca and Trnje (Danian).
In Vremski Britof section the author tried to find out whether genus Gyroplevra are
autochthous or allochthonous;they are found in numerous horizons together with
Foraminifera Rhapydionina liburnica. According to gathered data,Gyroplevra were frequently
deposited in the environment where Rhapydionina lived.
In the section Divaca Trnje the appearance of algae from genus Chara ,frequently found
together with snails , is researched. We stated that Haracea appear in the beds where
there are the snails as well there where they are missing . It is interesting that there
are besides snails in the beds near Divaca a lot of talus and other plant parts. In the
Trnje profile ,distantsome kilometers from Divaca only , there are namely oogonia only.
2.3 Connection of fissured zones with underground channels (Tectonical
investigations)
In 1991 and 1992 we started with detailed tectonic mapping of Hankejev kanal in
the scale 1:5000. In the first phase we limited on way and direction of tectonic crushed
zones in the limestone of Hankejev kanal. We were interested in connection of formation of
underground channel in primary phase with tectonic elements. With future investigations we
will consider lithological elements beside the tectonical ones which are important for
channel development.
Tectonic crushed zones in Hankejev kanal have two important directions, one is dinaric
direction NW-SE , the other is transverse (NE-SW). The direction E-W is well developed
just in some parts of the channel. First the channel has dinaric direction which in the
middle of the channel turns towards N. We can assume that direction of S part of the
channel crosses tectonic crushed zones. Nearly in the middle of the channel its direction
is parallel to direction of crushed zones. For the N part of the channel one could say
that it is much more parallel with the direction of the crushed zones than with the S one.
Among tectonic crushed zones broken and partly fault zones predominate while fissured
zones are less common.
We partially overlooked the tectonic conditions on the surface above the cave where the
ceiling thickness is about 100 metres. Detailed tectonic mapping of the surface in the
scale 1:5000 showed that dinaric and transverse dinaric directions are the most common on
the surface and in the cave. A certain coincidance between tectonic conditions on the
surface and in the cave exists , the question remains which properties on the surface
infer the most to the lower lying cave.
2.4 Flowstone datings
By U/Th method three samples from Skocjanske jame were tried to be dated.
Sample 1 (working S4)
The sample was taken in Paradiz close to the exit from the artificial tunnel.The flowstone
is deposited directly to dark Upper Cretaceous limestone , it is bedded , of white to
light brown colour. The sample belongs to the layer on the contact with limestone and
should tell when the flowstone deposition started.
Defined isotope values of U (238 , 234 , 232) and Th (232 , 230 , 228) on counter (incpm)
were too low to be treated by the computer.
Samples 2 (S 3/1) and 3 (S 3/6) are the bottom and the top of the stalagmite from Velika
dvorana.
Sampled stalagmite is about 30 cm high, of white color and covered with flood loam. It has
grown on the lower part of the breakdown.
Here too the measured values of U and Th on the counter were too low, in particular Th
value, this is why the age was not calculated.
The analyses were done on McMaster University (Hamilton , Canada).
2.5 Chemical properties of percolated water
In the year 1991 the basic properties of the precolated water were studied in
Hankejev kanal of Skocjanske jame. The thickness of the cave roof where the rainwater
infiltrates is up to 130 m and enables good organisation of the conduits assuring the
permeability of the trickles. In most cases the percolated water falls from the cave roof
about 100m deep through the cave air where it is well aerated and this fact controls the
intensive flowstone deposition.In the cave the percolated water appears in a sort of
belts. Dry sections are followed by wet sections with abundant trickles and big amount of
deposited flowstone.
Chemical analyses showed that these waters are pure. The o-phosphates are on the limit of
detection (0.01 mg/l), chloride contents below 3 mg /l, sulfate contents from 8 to 15 mg/l
, nitrates below 1 mg/l , with exception of dripping water in Martel's Chamber where it
contained 7 mg /lof nitrates and sulfates were the highest too This percolated water has
the lowest hardness and a bit higher non-carbonate hardness than the other percolated
waters .The surface above this part of the cave is not cultivated and there are no visible
reasons for any pollution.
Otherwise, the percolated waters are over-saturated with high calcium and low magnesium
hardness (some percents of the total only). The analyses results are presented on the
Table 1.
Tab.1
____________________________________________________________________
Spec.
Carb.
Site
Date el.c.
pH mekv l-l
Ca Mg Total
m S cm-l
____________________________________________________________________
Dezevna jama
18.12.91
383
8.3
4.15 4.17
0.19 4.36
09.01.92 456
8.1
4.94 4.95
0.15 5.10
Swidovo razgledisce 18.12.91 508
8.2
5.58 5.65
0.12 5.77
09.01.92 499
8.2
5.25 5.22
0.18 5.40
Putickova dvorana
09.01.92 542
8.1
5.91 5.91
0.12 6.03
Martelova dvorana 09.01.92 365
8.2
3.55 3.82
0.18 ____________________________________________________________________
Percolated water , falling on the flowstone in Putickova dvorana has the highest
specifical electrical conductivity , carbonate and total hardness of all the sampled
waters.In 1981 such high values were found in the percolated water feeding the gours in
the Dvorana ponvic and in the percolated water in Velika dvorana. The differences among
the hardnesses of percolated water which were sampled could be the result of different
ways ofpercolation and it is highly possible that in particular cases the flowstone
deposition occurs on the ceiling and on the walls of the channel , it means before the
sample is taken. Such case we found in Dezevna jama.
The comparison of pecolated water between Dezevna jama and the water in the gours some
meters lower shows that on this short way from 1 liter of water 1.17 mekv carbonates, 58
mg CaCO3 respectively , were deposited.
Comparing the chemistry of percolated water in Hankejev kanal with this in Velika dvorana
, one could suppose that the flowstone deposition in Velika dvorana is of the same
intensity or even bigger as the trickles there are permanent. Comparing these values with
the values in other caves of Slovenia these are the highest stated values which means the
biggest corrosion of the carbonate rocks in the cave ceiling, High hardness and strong
water aerationin spacious cave chambers additionally control the maximal flowstone
deposition.
Parallelly ,we analysed the sediments in the Reka riverbed regarding the organic carbon
and phosphates contents; the study is not yet finished.
2.6 Flowstone deposition from the climatic changes point of view
The main physical properties of Hankejev kanal (the main water channel) such as
rocks , tectonics, percolated water and of the karst surface (morphology, climate) were
gathered and compared with the flowstone growth and the places where it does occur.
Flowstone depositions in Skocjanske jame are concentrated on some places only. Opposite,
in Karst generally speaking , the cave walls are covered by flowstone everywhere , so that
bare rock wall is very difficult to be found. But where the flowstone is deposited ,the
cave formation is often found in a form of "coulees" (from the ceiling down to
the river bed ,it is 50m high) , including "giant rimpools" and terraced
flowstone , some ten meters big. On the special points flowstone is of ten deposited very
intensively: up to 5cm thick in 100 years or 0.5-1.0 dm3/m year. The material
was gathered for the article "La deposition des concretions dans Skocjanske jame
(Slovenia) du point de vue des changements climatiques" , intended to be published in
the proceedings of the international symposium in France.
2.7 Erosion and corrosion measurements in the active part of Skocjanske jame
In this part of the cave smaller rocky and sediment forms were mapped in detail.
A special attention was paid to microforms in order to establish the intensity of recent
erosion and corrosion.
In the Reka riverbed five areas were chosen where the sites for recent processes
measurements by micrometer were placed. Chosen sites are on the places where strong
erosion is obvious and on the places where the corrosion prevails. Altogether there are 30
measurement sites in the cave.
The sites for micrometer measurements are placed in the cave Ponor in Odolina too in
similar conditions than in Skocjanske jame rendering possible the comparison between them.
In this cave the first measurements, calculations respectively, were already done. A part
of the cave walls was namely written over in the first half of this century. On the places
where the walls were protected by the paint the rock juts out in relief already. As we
know the age of the paint, inscription respectively we have calculated on this base helped
by micrometric measurements the intensity of corrosion on the scalloped wall and it
amounts to 1.5 mm/100 years.
2.8 Rocky featuers
In the first period of the rocky relief studies and related speleogenetical
factors we intended to get acquainted and to document the particular rocky features making
part of the relief.
There are two sorts of rocky features, one as the result of the recent cave formation and
the features which are the trace of past development phases.The first ones are formed by
the Reka river flow and less expressively by the condense corrosion which is the effect of
air circulation with different temperatures and humidity. The second ones could be divided
on the traces of water flow deeper in the phreatic zone and on the traces of paragenesis.
We gathered the data of form and position of characteristical scallops and rock-mills and
we shall try to define their origin and development in detail.By the results of surface
rocky features studies which were documented by electronic spin microscope we shall try to
define the processes which form the rocky rim of the cave.
The aim of further investigations is definition of origin and development of the rocky
features composing the rocky relief and the definition of its speleogenetical meaning.
3. BIBLIOGRAPHY RELATED TO WORK ON THE PROJECT No. 299
Knez, M., 1991: [Sedimentological and stratigraphical properties of
limestones from Skocjanske jame area (Outer Dinarids)].- The Second International
Symposium on the Adriatic Carbonate Platform , Abstracts , 105 , Zagreb
Kranjc ,A.&A.Mihevc ,1991:[December Floods along Notranjska Reka River].- Ujma , 5 ,
142-144 , Ljubljana
Kranjc , A. & M. Kranjc , 1992: Older Theories on Underground Accumulations in Karst.
-Karszt es Barlang , Special Issue 1992 , 63-66 , Budapest
Kranjc , A., 1992:[Older theories on karst and underground water].-Zivljenje in tehnika ,
43 , 6 , 45-47 , Ljubljana
Zupan , N., 1991:Flowstone datations in Slovenija.- Acta carsologica , 20 , 189-204 ,
Ljubljana
TYPICAL KARST AREA-SKOCJANSKE JAME (SLOVENIA
,Sept., 1992)
Dr. Andrej KRANJC (National Coordinator)
1. INTRODUCTION
According to program and plan for 1992 we investigated, studied
respectively the following topics in the area of Skocjanske Jame Karst:
- new survey of Hanke's Channel and history of Skocjanske jame investigation (A. Mihevc
& A. Kranjc)
- lithostratigraphy and paleoecology of Skocjanske jame Karst (Geological investigations)
(M.Knez)
- connection of fissured zones with underground channels (Tectonical investigations)
(S.Sebela)
- physical and chemical characteristics of percolated water (J. Kogovsek)
- erosion and corrosion measurements in the active part of Skocjanske jame (A.Mihevc)
- rocky features(T. Slabe).
2. PRELIMINARY RESULTS
2.1 New survey of Hanke's Channel and history of Skocjanske jame
investigations.
In order to achieve the foreseen researches, to locate the researches
respectively , the detailed survey of the Hanke's channel was necessary. This is the
biggest active water channel in Skocjanske jame and the existing surveys(from the end of
the last century),the plan respectively did not meet the modern requirements.
In 1992 the lower part of the cave was surveyed as a continuation from the year 1991 and
documentation (Basic Cave Survey in the scale 1:500 and 1:250 respectively , cross and
longitudinal sections) was prepared.
The review of older sources on investigation , exploration and survey of Skocjanske jame ,
of the Hanke's channel in particular , with a special accent given to the names of
particular parts of the cave and to the single details was carried on. Special report of
the investigations of Skocjanske jame in the last decade was prepared.
2.2 Lithobiostratigraphy and paleoecology of Skocjanske jame Karst (Geological
investigations)
From lithobiostratigraphic and paleoecological point of view four profiles
(Vremski Britof , Skocjanske jame , Trnje and Divaca) were studied. The first two are
found in Vreme beds , the second two in those Kozina beds containing haracea and snails
with some milliolids. More than 100 thin section were made(for microscopic and macroscopic
analyses), the more important were photographed. More than 60 field photographs were
made.On the base of detailed profiles mapping the stratimetric profiles and lithological
columns were sketched.
2.3 Connection of fissured zones with underground channels (Tectonical
investigations)
During 1992 we continued with detailed tectonic mapping of Hankejev kanal and the
surface above it in the scale 1:5000. The data were drawn on the map and it is clear that
the collapse doline Mali dol lies on the crossing of two strong tectonically broken zones.
It was also stated that the main directions of tectonically broken zones and beds in the
cave and on the surface complement.
2.4 Chemical properties of percolated water
In the year 1992 we analysed 16 samples of the percolated water (mostly polluted
water in Mahorciceva jama) and 2 samples of the Reka river water. We measured runoff , SEC
, pH , and temperatures in the cave itself , while in the laboratory we analysed calcium ,
total hardness ,chlorides , nitrates , o-phosphates , sulfates , the content of oxygen ,
COD , and BOD.
2.5 Erosion and corrosion measurements in the active part of Skocjanske jame
Regarding the recent measurements by micrometer the net of control points was
established to the number of 19. At all the points the first (initial) reading was done,
at the points where the flowstone is deposited , also the first measurement reading.
In the nearby cave Mejame , the group of French divers explored the siphon lake-on the
depth of 17.6 m the water disappears in inaccessible fissures.
2.6 Rocky festures
The results of field work were treated in the doctorship thesis of the researcher
, member of a team. There the rocky features are documented, explanation of their genesis
is given (using also electron microscope to distinguish the actions of corrosion and
erosion respectively) , and the rocky relief of the cave as a whole was evaluated as a
"speleogenetical trace".
3. BIBLIOGRAPHY RELATED TO WORK ON THE PROJECT No. 299
Kranjc , A. & J. Kogovsek & S. Sebela , 1992: Les
concretionnements de la grotte de Skocjanske (Slovenia) et les changements climatiques.
Karst et evolutions climatiques, Bordeaux Slabe ,T., 1992: Jamski skalni relief kot odsev
speleogenetskih dogajanj v izbranih predelih slovenskega krasa. Doktorsko delo, 1-243,
Ljubljana
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