Water from an Abyssinian well is, as a rule, pure and high-quality water. The feeding zone of this water is located on a vast territory. That is, the precipitation can feed it many kilometers from you, it gradually migrates underground - and you pump it out in your area.

According to the mineral composition, this water is distinguished by a low content of salts of hardness, manganese and other elements.

Bacterial contamination is also extremely low, since sand is an excellent bacterial filter, sand adsorbs on itself a huge amount of organic matter. Sand is also used in backfill water clarifier filters. Unlike a conventional well, water from an Abyssinian well is taken from the depths, so it does not include the perchage, which is inherent in some wells of concrete rings.

The only headache of water from a needle driven needle in some regions is iron. IRON IN WATER IS PRESENT ANYWHERE, IN EACH LOCATION BY DIFFERENT.  According to the content of iron, water from different aquifers can differ!

For example, the 1st water is good, but it is too close to the surface, the 2nd water is red, the third is good.

Unfortunately, it also happens that there is only one aquifer in the given area - and in it water is red, or drifting with time. In our practice - each well is individual!

This is the situation, for example, in the Moscow region - in one village water from the Abyssinian wells is clean, in the other - glandular.

And in the Stavropol Territory, for example, all the water is good, but to pierce it with the spear of an Abyssinian well it is necessary to pierce a considerable layer of brown clay.

The quality of water from an artesian well

Water from deep artesian wells, on the contrary, contains a large amount of hardness salts, iron in a dissolved 2-valent form, manganese and other elements that dissolve in water. 2-valent iron is soluble iron, while in air in such water, iron passes into a 3-valent form and precipitates. This is manifested by rusty flakes, the water becomes brown, a precipitate appears. But this again is not everywhere!

In practice, there are such cases:

1. We killed an Abyssinian well - the water in it is clean, good. Neighbors drilled an artesian well - the water in it is ferruginous.
2. We killed an Abyssinian well - the water in it is glandular. We drilled an artesian well - the water is clean. And the air does not brown.

In general, a lot of situations.

But in general, the water from the Abyssinian wells has proved itself very well! And if on your site the ground allows you to make an Abyssinian well, then it's definitely better to do it!

What are the features of artesian water in the Moscow region. That allows to reveal the analysis on quality of the given water environment. Features of strata groundwater  Moscow region. What composition are the artesian waters of our region. Analysis of water components from artesian beds, assessment of their impact on humans. What factors affect the quality of artesian waters in the Moscow Region. Artesian water in the Moscow region is characterized by a large content of small particles of sand and clay. The quality analysis often shows an excess of the permissible concentration of ammonia, fluorine, hydrogen sulphide and manganese.

Features of underground waters of the Moscow region

In our region, consumers are available several types of groundwater, lying at different depths:

• Ground water environments. These are the layers closest to the earth's surface.
• At a greater distance from the earth's surface are the ancient aquifers of the Jurassic-Cretaceous period.
• Even lower are the aquifers of the Carboniferous period. They are the most clean, because they differ in isolation from external factors. In these layers there is the best artesian water, since the level is located at a considerable distance from the lower unduly mineralized horizon.
• The deepest aquifers, characterized by a high degree of saturation with minerals.

The purity and quality of water in the first two layers are highly dependent on external man-made factors. They are often polluted by sewage and surface waters. This is especially noticeable during the flood period and during the autumn rainy season.

Artesian water: quality

Artesian water in the Moscow region is characterized by high iron content and high rigidity. Many people are familiar with such a situation, when crystal clear water, just recruited from a well, becomes directly brown and cloudy before our eyes. This is due to the oxidation reaction of iron dissolved in water when it interacts with oxygen.

Current standards for drinking water limit the iron content in this aqueous medium by 0.3 mg / l. For artesian waters of the Moscow region is characterized by an increased concentration of this element in the range from 0.5 to 20 mg / l.

As for the water hardness, according to the regulatory documents, this indicator should not exceed 7 mol / m³. For artesian water in the Moscow region, a stiffness index of 3-10 mol / m³ is characteristic. This indicates that in the aqueous medium, the increased content of sulphates, dissolved calcium and magnesium salts.

In addition, water from an artesian well in this region is characterized by a high content of impurity particles. In this case, it is small particles of clay and sand. Also, the analysis of artesian water in certain regions of the Moscow region revealed an excess of the concentration of certain chemicals, namely:

• fluorine particles;
• elements of ammonia;
• manganese;
• hydrogen sulphide.

Features artesian water basin suburbs

The artesian waters of this region are more often carbonate. The aqueous medium is usually fresh with a degree of mineralization equal to 0.4-0.6 g / l. The quality of these waters is usually very good, especially for the waters of the hydrocarbonate and magnesium-calcium groups.

However, some layers of artesian waters are polluted from the upper aquifers (groundwater). The water environment they have is the same, fresh. The environment of these contaminated horizons is characterized by the presence of chlorides and hydrocarbons, as well as increased rigidity due to the high concentration of sodium, magnesium, calcium. The composition of such artesian water is not very good, so it needs careful cleaning before use.

Analysis of underground artesian waters

Artesian water of the highest category must comply with the requirements of regulatory documents. The main MPC of substances for such waters are normalized in GOST 17.1.1.04-80. The chemical composition of artesian waters is influenced by the following factors:

1. Features of the water horizon.
2. Components of the surrounding rock formations.
3. The degree of protection from pollution by sewage, water from other layers.

Analysis of artesian waters of the Moscow region showed such features of the aquatic environment:

• The concentration of dissolved mineral components is exceeded and is 20 mg / l.
• Also higher than the norm is the concentration of hydrocarbonates, which creates an aqueous environment with increased alkalinity.
• Due to the overabundance of calcium and magnesium salt compounds, the aqueous medium is characterized by increased stiffness. Normally, this parameter should be equal to 2.5-3 mg / l, and in the studied aqueous medium it is equal to 4.3-5.6 mg / l.
• During the analysis, a low concentration of chloride particles and sulfate elements was detected.
• Due to the fact that these aquifers are surrounded by a rock with a certain content of celestite, strontium is found in the water. Usually its concentration is 2-5 mg / l. This number increases as the aquifer decreases.
• According to SanPiN 2.1.4.1074-01, artesian drinking water should have an iron concentration of not more than 0.3, and magnesium particles should not exceed 0.1 mg / l. In the analyzed aqueous medium, these values ​​were significantly higher than normal. In principle, these components of water, even in large quantities, are not harmful to humans, but they contribute to the development of glandular bacteria, which cause increased corrosion of pipelines. The method of aeration is used to purify artesian water from these components.
• The increased concentration of fluoride particles in artesian water can lead to problems with bone tissue, so this aqueous medium is purified by filtration through sorbents.
• Exceeding the concentration of hydrogen sulphide in the artesian aquatic environment leads not only to a deterioration in the organoleptic properties of water, but also is harmful to humans. The concentration of this substance is limited by regulatory documents and should not exceed 0.003 mg / l.

To draw conclusions about the purity and quality of artesian water, it is necessary to conduct a laboratory analysis. You can order such a check in our independent laboratory. To do this, you need to contact us by phone on the website. The price of the check depends on the number of analyzed components and is specified when ordering.

Many people ask whether it is possible to know in advance what the chemical composition of the water in the future well will be and whether it will change after some time after the operation of the water intake. Having planned borehole drilling  on a suburban site, the owners are trying to learn the characteristics of the water from neighbors, in the areas of which there are already wells or wells. The second way is to get the water analysis data, indicated in the cadastral documents for the wells.

The chemical composition of the water in the well can vary with time

Experts believe that the most accurate information about the chemical composition of water can be reflected only in relation to "young" wells. If the cadastres indicate the beginning of this century, the quality of water in such wells does not always match the documentary indicators. Drilling masters know many cases when the chemical composition of water from a subterranean source changed quite significantly even after five to seven years from the time the well was drilled. This is a consequence of the fact that the properties of water have changed in the entire water-bearing layer because of external factors that have different effects on natural objects.

On the basis of the above, a reasonable question may arise: is it necessary to purchase an expensive water treatment plant that can work for several decades if in five to seven years it is necessary to replace it with a new one that is more suitable for treating water with changed chemical indices? Experts consider such an opinion unreasonable. According to statistics, in every tenth well, the chemical composition of water changes dramatically in 10-13 years. Buying cheap equipment for water treatment can turn into problems: frequent breakdowns, low cleaning efficiency, short service life.

The quality of water from artesian wells and wells "to the sand"

Most of the complaints about changes in water quality come from the owners of wells "on the sand." As a rule, in water extracted from water-saturated sandy rocks, there is a high concentration of iron. But there are cases when, after drilling a well, water samples from it show the norm of the content of dissolved iron. But after a while the amount of iron suddenly rises so much that all the norms of the MPC of this chemical are violated in drinking water.

Most likely, scientists believe, this is due to a change in the way of infiltration of the aquifer, for example, when atmospheric precipitation begins to seep into the ground through layers of peat soils. Unlike sand wells, artesian springs have a more stable water composition.

Which of the sources is preferable: an artesian or sandy well

In the Leningrad region, wells "on the sand" are mostly chosen by the owners of small country plots - country and horticultural plots. Artesian wells are preferred by owners of country houses as sources of autonomous water supply, because they need a source with a high production rate because of the large number of water-extraction points. The second special case of the use of artesian water intake in the country construction is a collective well.

Of the total number of wells ordered in drilling companies, collective bore no more than 10%, and drilling is mainly builder, erecting a new cottage community. Private owners also have to drill an individual well, as usually all neighbors are already provided with water from their own water supply sources.

It should be noted that the quality of water from an artesian well is usually higher than from a well to sand or a well.

"How does the quality of water in the wells change over several years of operation", БК "SEARCH", tell friends:   April 13th, 2016

Artesian wells take water from limestone aquifers. But, despite the good natural filtration, although its water is the cleanest in comparison with other sources, it still has some pollution.

Whence come impurities in the well water? Let's try to figure out what exactly affects the quality of artesian water.

The main factor of groundwater pollution is its contact with a mixture of sand and clay, the so-called Quaternary deposits. The layer of these deposits is located directly on the limestone aquifer. Limestone has small cracks, through which the waters of quaternary deposits penetrate the horizon, bringing into its water iron (up to 10 mg / l).

The next thing that can cause contamination of artesian water is the technology of drilling wells. One of the errors in drilling is the pairing of the horizons - when between the upper aquifer  and the limestone horizon lacks tightness.

Requirements and norms for water quality

There are special standards that specify the requirements for the quality of water from underground sources. So, iron in such water should contain no more than 1 mg per 1 liter, sulfates - not more than 500 mg / l, total hardness - not more than 7 meq / liter. Such requirements exist for many chemical elements, compounds and even for the number of microorganisms in 1 liter of water there are norms. Compliance with the drilling technology and hydrogeology of the area greatly contributes to the reduction of impurities in the well water.

For example, knowing that the content of minerals and fluorine in water increases as the horizon "falls" in depth, it is necessary to drill wells for water in the area under which the aquifer lies closer to the surface, unless, of course, it does not violate health standards  (location of cesspools, garbage dumps, etc.). But on the other hand, it is believed that iron brings Jurassic clays, and that to reduce the iron content in water, the water intake part of the well is located deeper.

The quality of water in the suburbs

The underground waters of the suburbs are rich in iron.  It is contained in groundwater and in the aquifer, formed by coal deposits. You can not mix the waters of different horizons with the waters of limestone deposits, and secondly, the upper layers of limestone (1-3 m) must be thoroughly cased with pipes.

Also, iron can be located between the water horizons in the clays, which (horizons) they share. Such clays, for example, are located between Kasimov and Gzhel limestone horizons. Such a layer when drilling artesian wells should be isolated by deaf casing sections. In general, hermetically sealed pipes in the casing will avoid the entry of other water, and therefore of various impurities, into the well.

In order to know the chemical composition of water from your well, it is necessary to perform a water analysis in a specialized laboratory or organization that has such a laboratory. Based on the data of such a water analysis, it will be possible to proceed with the selection of a water treatment system, which will make the consumption of water safe for home appliances and your health.

  WATER OF MOSCOW REGION

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Ecological problems of groundwater use

UNDERGROUND WATERS OF THE MOSCOW REGION: ECOLOGY AND SANITARY-HYGIENIC CHARACTERISTICS

· General ecological problems of using groundwater for the needs of domestic and drinking water supply

Underground waters are much more protected from external factors, compared to surface waters, but pollution of aquifers still occurs. According to the official data of the State epidemiological supervision for 1999, more than 1800 foci of groundwater pollution were registered in the country, of which 78% are located in the European part of Russia. According to expert estimates, the total consumption of contaminated groundwater in 1999 was 5-6% of their total quantity used for drinking water supply, and, unfortunately, this figure increases every year.

Above all, aquifers are exposed to pollution, located above the level of waterproof rocks. In densely populated areas, pollution also penetrates into deeper horizons due to their intensive evacuation. Thus, the so-called depression funnels are formed, in which the groundwater is replenished from the above contaminated horizons. One of these funnels is noted in Moscow and the surrounding areas.

· Physical-geographical characteristics of underground waters of the Moscow region

Underground waters in the Moscow region have 5 levels of occurrence:

· Groundwater

· Intermortem half-water aquifer

· The Upper Jurassic horizon

· Medium-carbon pressure head horizon

· Lower carbonaceous pressure horizon

The first three levels are higher than the first from the surface of the waterproof horizon, the depth of which in the Moscow region is very variable and varies from 1-3 to 70 m. Groundwater is characterized by a lack of pressure, sharp differences in the depth and thickness of the aquifers. Below the groundwater level, there are 2 more aquifers that are hydraulically connected to groundwater, this is an inter-moraine semi-pressure aquifer and the Upper Jurassic horizon.

All three of the horizons are fed mainly by atmospheric precipitation and surface runoff. Replenishment of water in them occurs mainly in the spring. The outlet to the surface of groundwater occurs in the valleys of small rivers and streams, the waters of the intermorennial semi-pressure horizon seep to the surface through ancient and modern sand deposits (alluvium) in river floodplains, the waters of the suprajur aquifer come to the surface through large ascending sources located in river beds.

The medium-carbon and lower-carbon pressure aquifers lie at a depth of more than 100 m in limestone and dolomite deposits of the Carboniferous period. They are characterized by considerable power - up to 50-70 m and relative hydraulic isolation from other aquifers. These waters are the main source of water supply to cities and towns in the Moscow region.

· Chemical composition of groundwater

In general, the groundwater of the Moscow region is characterized by a high degree of mineralization, the concentration of salts reaches 20 mg / l. Water has an increased alkalinity, due to a high content of hydrocarbonates, as well as rigidity due to the abundance of calcium and magnesium salts. In some cases, the MPC is exceeded for the content of iron and manganese, as well as an increased concentration of fluoride compounds.

The chemical composition of groundwater is determined by the following factors.

· Type of food

· Composition of rocks

· The degree of isolation from surface runoff and other aquifers

Groundwater in the Moscow region is a hydrocarbonate-calcium-magnesium type with a small content of sulfates and chlorides. In the formation of their salt composition, the main role is played by the infiltration of atmospheric precipitation through the soil. This is associated with an increased concentration of iron and manganese salts in them. In addition, under the influence of contaminated surface runoff, in some cases an increased content of cadmium, aluminum, lead, arsenic, nickel, chromium, cobalt, vanadium is recorded.

Data on exceeding the MPC for one or more of these indicators are available for wells in the vicinity of Volokolamsk, pos. Shcherbinka, Istra, and other large industrial regions. In areas of intensive agricultural activities - in Mozhaisk and Istra regions, as well as in the vicinity of Zvenigorod in groundwater, organophosphorus pesticides have been found, as well as an increased concentration of nutrient elements, in particular ammonium nitrogen.

Pollution of groundwater can be associated not only with the infiltration of certain substances through soil horizons, but also with violation of the norms of operation of water intake facilities and the absence of strictly protected zones of sanitary protection. In particular, this is due to the majority of cases of bacterial contamination of underground sources.

The waters of the intermorennial semi-pressure and super-Jurassic pressure head differ in their physicochemical properties from groundwater, since in most cases they are connected hydraulically with them. The level of contamination decreases with depth. The deepest waters of the mid-carbon and low-carbon pressure head are more mineralized than ground waters. They practically everywhere refer to a hydrocarbonate-calcium-magnesium type with a small admixture of sulfates and chlorides. However, in some localities, the sulfate prevails in the salt composition.

Due to the presence of minerals of celestite and strontium in rocks forming aquifers of deep occurrence, an increased content of strontium (up to 2-5 mg / l) is observed in groundwater. The concentration of strontium in water gradually increases with the depth of the wells. In the waters of the Middle Carbon, there is often an increased content of fluoride compounds. In the wells of Mozhaisk and Ruza regions, the concentration of fluorine often exceeds the MPC equal to 1.2 mg / l.

· Sanitary and hygienic characteristics of groundwater and methods for their purification

Underground waters of the Moscow region are characterized by increased rigidity. The presence of calcium and magnesium ions determines the overall rigidity. Carbonate hardness depends only on the concentration of hydrocarbonates and carbonates of these elements. The average total hardness of water in the Moscow region is in the range 4.2-5.7 meq / liter at a standard of 8.0 meq / liter. (normal total water hardness, at which the consumer has no problems - 2.5-3.0 meq / liter).

Most effective way  water softening is the method of ion exchange. Its principle is the property of certain substances in contact with water to replace the ions of undesirable elements contained in the solution with safe ions of sodium, hydrogen, etc. Usually, water filters use filters loaded with special polymer ion-exchange materials. The efficiency of their operation is determined by the ion-exchange capacity of the load, which in turn depends on the operating mode and, in particular, on the filtration rate.

One of the most pressing problems in the use of underground water in the Moscow Region for drinking water supply is the increased concentration of iron and manganese. The MPC for these elements in accordance with the Sanitary Rules and Norms adopted in 2001 (SanPiN 2.1.4.1074-01) is 0.3 and 0.1 mg / L, respectively. Despite the absence of a pronounced toxic effect, these elements are important in sanitary and hygienic respect, since their concentration determines the intensity of development of specific microorganisms - iron bacteria, colonies of which settle on the internal surfaces of pipes and metal structures. In the process of vital activity these organisms secrete iron-oxidizing enzymes, which increases the rate of corrosion processes tenfold. In this case, insoluble oxidation products are released into the water, which increases the turbidity of the water and gives it color.

Various methods are used to purify water from excess iron. The most accessible among them is the aeration of water and treatment with its oxidizers - chlorine, permanganate, ozone, etc. Effective also is the use of filtration through ion-exchange filter elements.

In some areas of the Moscow region in the underground waters there is an increased content of fluorine. This element is necessary for the human body, where it plays an important role in the formation of tooth enamel. At the same time, an increased concentration of fluoride leads to a lesion of bone tissue, known as fluorosis.

To remove excess fluorine concentration, filtration through sorbents - oxides and hydroxides of aluminum and magnesium, calcium phosphate, basic aluminum salts is used.
Recent cases of pollution of groundwater make the problem of cleaning up from organic pollutants and, in particular, pesticides an urgent one. Most of these compounds have high toxicity and their presence in drinking water is highly undesirable. To purify water from organic materials, it is treated with various oxidizers - chlorine, permanganate, ozone. A high effect is obtained by sorption on filters loaded with activated carbon. The cheapest way to remove organic matter is aeration.

See also ESTIMATION OF ENVIRONMENTAL STATUS OF THE WATER SOURCE ...
V. Lukin,
ecologist, Ph.D.
  When quoting an article, please do not forget to give a link to the source. Thank you.

Hydrogeology

HYDROGEOLOGY (from hydro ... and geology), the science of underground waters; studies their composition, properties, origin, patterns of distribution and motion, as well as interaction with rocks
The structure of hydrogeological research includes the following types of services:

The study of water resources for solving the problems of water supply
- Justification of the standards for the permissible environmental impact (EIA, VCP, permissible withdrawal of groundwater in assessing their operational reserves)
- Creation of monitoring systems for subsoil, surface and groundwater bodies, water management systems
- Research and forecasting of anthropogenic impact on the environment
- Information support for environmental management
- Resolution of water management problems of mining enterprises
- Consulting services and expert opinions

Depth map for artesian wells

Map of depths for wells on the second water-bearing sand and wells.

The conventional hydrogeological scheme MO
(major aquifers)

2 horizons: Klyazminsko-Assel, in some places - Kasimovsky
Lmax, m - 150
Nmax, m - 50
Klyazminsko-Assel (the probable debit is 0.3 ... 27 l / s)
Composition:
Fe (mg / l) - 0.2 ... 0.7 (excluding Klin and Taldom)
F (mg / l) - 0.2 ... 1
F - 4-7 m-e / l
HCO3-, SO4-2, Ca2 +, Mg2 +
Kasimovsky (the probable debit is 2 ... 8 l / s)
Composition:
Fe (mg / l) - 0.3 ... 0.4 (Dmitrov, Noginsk, Orekhovo-Zuevo - 1.5 ... 3.9)
F (mg / l) - up to 3,6
F - 5.2 ... 6 m-e / l
H2S (Dmitrov) - up to 0,003 mg / l

· II district

2 horizons: Kasimovsky and Podolsky-Myachkovsky
Kasimovsky (the probable debit is 0.5 ... 7 l / s)
Lmax, m - 20 ... 125
Nmax, m - 10 ... 60

Composition:
Fe (mg / l) - 0,2 ... 0,9 - up to 5 (Yegoryevsk, Klin, Solnechnogorsk, Khimki)
F - 3 ... 7 m-e / l
HCO3-, Ca2 +, Mg2 +, Na +
Podolsko-Myachkovsky - Balashikha, Egorievsk, Khimki (the probable debit is 0.5 ... 7 l / s)
L, m - 25 ... 180
N, m - 20 ... 90

Composition:
Fe (mg / l) - 0,1 ... 1,0 - up to 6 (Egorievsk, Klin, Solnechnogorsk, Khimki)
F - 3,5 ... 7,2 m-e / l
HCO3-, Ca2 +, Mg2 +, Na +

· III district

2 horizons: Podolsko-Myachkovsky, in some places - Kashirsky, partly both (probable debit - 1,5 ... 7 l / s)
West Side:
Lmax, m - more than 100
H, m - more than 100

East End:
L, m - 20 ... 80
N, m - 18 ... 40

Composition:
Fe, mg / l - 0.5 ... 2.3 - up to 7.5 (Narofominsk)
Ж, м-э / л - 5 ... 7
H2S, mg / l - up to 0,003 (in some places)

· IV district

2 horizons: Kashirsky and Oksko-Protvinsky (the probable debit is 0,7 ... 7 l / s)
L, m - 80 ... 160
N, m - 80 ... 100 (up to 150)
Composition:
Fe, mg / l - 0.5 ... 2.5
F, mg / l - 0.2 ... 1.0 - up to 4.8 (Mozhaisk)
Ж, м-э / л - 5 ... 7,5
СО32-, Ca2 +, Mg2 + - 0,4 g / l

Oksko-Protvinsky horizon (the probable debit is 0,1 ... 4 l / s)
L, m - 20 ... 80
N, m - 15 ... 30
Composition:
F, mg / l - 0,1 ... 1,5
F, mg / l - 0,1 ... 1,5
Ж, м-э / л - 4 ... 7,7
СО32-, Ca2 +, Mg2 + - 0,4 g / l

In the explanations, L is the depth of occurrence of limestone in meters (from the bottom), H is the head of water in the well (the distance from the surface of the earth to the level of water that has settled after pumping), the rigidity (G) and hydrogeochemical characteristics of the water is its salt composition.

The chemical composition of the groundwater of limestone horizons is predominantly hydrocarbonate, calcium-magnesium, often with a high content of iron and fluorine. The maximum permissible concentration (MPC) of iron and fluorine is 0.3 mg / l and 0.7-1.5 mg / l, respectively. Water hardness, determined by the total content of calcium and magnesium, expressed in milligram equivalents per liter, does not formally exceed the MPC level (7 mg-e / l). At the same time, for normal operation of domestic water equipment and for drinking purposes, the rigidity should be reduced to a level of 2.5-3 mg-e / l.

A serious problem can be created by hydrogen sulphide, dissolved in underground water, whose characteristic smell (rotten eggs) is captured at concentrations even in thousandths of mg / l.

The red digits in the diagram are the interval of occurrence of the water-bearing sands, the blue figure below them is the probability (1 = 100%) of the presence of water (according to the actual drilling data of the companies KVO and Mosgeoplan).
A. Sekisov,
hydrogeologist, D.Sc.

Limestones in the Moscow region
The ancient limestones of the Carboniferous period lie in the Moscow suburbs at depths of 20 meters (south, southeast, to over two hundred meters (northeast) .The marks are given from the bottom (lower boundary of the layer). The limestone layers can significantly change their thickness (thickness) and form (representing the folds) .In addition, within the deposits of limestones themselves, there may be thin clastic strata of clay and silicified areas.