Porosity groundwater

10 Exercises. 1) A 100 cubic centimeter (cm 3) sample of soil has an initial weight of 227.1 grams. It is oven dried at 105°C to a constant weight of 222.0 grams. The sample is then saturated with water and has a weight of 236.6 grams. Next, the sample is then allowed to drain by gravity in an environment of 100% humidity and is reweighted at ...

Hydraulic gradient. ,. Darcy (1856) expressed that the specific discharge through porous medium is directly propor- tional to hydraulic head or head loss ...The groundwater table is located at a depth of 3.5 m below the ground surface. Compute the a) total vertical stress, b) pore water pressure, and c) effective vertical stress at the following depths below the ground surface: 2.2 m (Point A), 4.0 m (Point B), 6.0 m (Point C), d) draw a sketch and show the points( A, B, C) on the sketch.The core data show that the salt rock is a dense lithology with a porosity of 1.4-4.05% and low permeability. In addition, ... lifting force of the salt cavern is composed of the internal pressure in the salt cavern and the buoyancy force of groundwater on the rock mass and salt cavern. The stability coefficient of the salt cavern is defined ...from parent minerals, as particle size decreases, and as porosity increases. These studies will help to elucidate the surface area term necessary to better inform reactive transport models of shale-based soils. ... maximum groundwater concentration at a receptor location on the edge of the waste unit, and the maximum contaminant concentrations ...porosity flow stage to radical flow stage, and as theconductivity indexincreases, theposition of type curves also increases. The increase in the curve position reflects the improvement of seep-age resistance caused by the permeability and porosity of microfractures decreasing as df-θf- DE < 0. (4) For the vertical fractured well with ...Groundwater is fresh water (from rain or melting ice and snow) that soaks into the soil and is stored in the tiny spaces (pores) between rocks and particles of soil. Groundwater accounts for nearly 95 percent of the nation’s fresh water ... Porosity (how well rock material holds water) is also affected by the shape of rock particles. Round particles will pack …Groundwater can be defined as the water stored underground in rock crevices (fractured media) and in the pores of geologic materials (porous media) that make up ...In an area of 100 ha, the water table dropped by 4.5 m. If the porosity is 30% and the specific retention is 10% determine- (i) the specific yield of the aquifer, (ii) change in ground water storage. Solution: Porosity = S y + S r. 30% = S y + 10% S y = 30 – 10 = 20% or 0.2 . Change in ground water storage = Area of aquifer × drop in g.w.t ...

Dec 29, 2020 · Groundwater is water found below the water table in the zone of saturation within the pores and cracks of a wide variety of earth materials. Groundwater occurrence in porous material is described in terms of total porosity, effective porosity, void ratio, volumetric moisture content, specific yield, and specific retention. ... porosity and permeability, so they are aquifers. Groundwater is filtered through aquifers, and this purifies the water. Jacobsville water is usually safe ...Groundwater can also come to the surface as a spring or be pumped from a well. Both of these are common ways we get groundwater to drink. About 50 percent of our municipal, domestic, and agricultural water supply is groundwater. How does the ground store water? Groundwater is stored in the tiny open spaces between rock and sand, soil, and gravel.Porosity is an intrinsic property of every material. It refers to the amount of empty space within a given material. In a soil or rock the porosity (empty space) exists between the grains of minerals. In a material like gravel the grains are large and there is lots of empty space between them since they don’t fit together very …Two billion people rely on underground aquifers for their freshwater. Humans exist on a short leash. A person can only last around three days without drinking water. Put that way, human life is absurdly fragile; plenty of other organisms ca...Groundwater in the Driftless Area of northwestern Illinois is a very hard Ca–Mg-bicarbonate-type water that reflects the dolomite aquifer material in this karst region. Groundwater in shallow aquifers has a short residence time and is susceptible to surface-borne contaminants. Deeper aquifers have distinct chemistry indicating longer flowpaths, …Dec 26, 2021 · At this point we have to deal with the physics of groundwater movement. This comes under a branch of fluid dynamics known as flow through porous media. The essential features of flow through porous media are in common with flow in pipes and channels, (Chapter 1), but certain aspects are distinctive to groundwater flow. Porosity (n) is a directly measurable aquifer property; it is a fraction between 0 and 1 indicating the amount of pore space between unconsolidated soil particles or within a fractured rock. Typically, the majority of groundwater (and anything dissolved in it) moves through the porosity available to flow (sometimes called effective porosity).

The majority of freshwater on earth is found in frozen glaciers and ice caps. This frozen water accounts for 68.7 percent of earth’s freshwater, with 30.1 percent found in groundwater. Only 1.2 percent of fresh water is exposed to the surfa...The hydrogeological properties, porosity and permeability, of geological layers and their spatial distribution vary for many reasons, the type of rocks or ...30 Kas 2017 ... ... porosity; 22. Figure: Relation Between Texture and Porosity ○ Well –Sorted Sand Having High Porosity ○ Poorly- Sorted Sand Having Low Porosity ...13 Ağu 2019 ... Aquifer Types. Page 5. Aquifer porosity. Page 6. Porous rock vs Fractured rock. Page 7. Conceptual model of groundwater flow. Page 8. Page 9 ...Review groundwater flow, aquifers, porosity and permeability with students (see Introduction section). To complete activity as an inquiry-based project: Write porosity and permeability on the board as vocabulary terms and define each. The porosity of a material is a measurement of how much of its volume is open space (also called pore space ...Porosity is a fraction between 0 and 1, typically ranging from less than 0.005 for solid granite to more than 0.5 for peat and clay . The porosity of a rock, or sedimentary layer, is an important consideration when attempting to evaluate the potential volume of water or hydrocarbons it may contain.

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Groundwater exploration by test drilling in the district commenced in fifties and was continued till 2002-2003. ... porosity and permeability. The hydraulic conductivity of the soils ranges from as low as 0 for saline and alkali soils in the western part to more than 7cm/hr forporosity. Meanwhile, the TDRs were attached to the soil column and sealed well to avoid leakage. For saturation, deaerated blue water was prepared using a brilliant blue dye tracer (0.2 g/L concentration) to enhance the visibility of the water. The up-flow saturation technique was adopted, and an additionalGroundwater moves significantly slower than surface water. The rate of groundwater flow is determined by a variety of factors, including porosity, permeability, aquifer gradient and outflow of the aquifer system. Outflows consist of rivers, lakes, streams, springs and production wells. For groundwater systems, changes in density and viscosity caused by temperature need to be considered when computing hydraulic conductivities. Dynamic viscosity and density of water as a function of the water temperature is shown in Figure 28. Temperature has a more significant impact on viscosity than density. 13 Ağu 2019 ... Aquifer Types. Page 5. Aquifer porosity. Page 6. Porous rock vs Fractured rock. Page 7. Conceptual model of groundwater flow. Page 8. Page 9 ...

Porosity is a measure of how much water can be stored in geological materials. Almost all rocks contain some porosity and therefore contain groundwater. Groundwater is found under your feet and everywhere on the planet.The groundwater velocity, v, is higher than the specific discharge because the water can only pass through the portion of the cross-sectional area that is connected pore space, n e. That cross-sectional area is the product of the area of porous medium and the effective porosity, n e. where V is the velocity of the groundwater, and n is the porosity (expressed as a proportion, so if the porosity is 10%, n = 0.1). We can apply this equation to the scenario in Figure 11.6. If we assume that the hydraulic conductivity is 0.00001 meters per second (m/s), we get q = 0.00001 × 0.08 = 0.0000008 m 3 per second per m 2. If the ...Jul 13, 2022 · The analysis of the spatiotemporal characteristics of groundwater level variation is a prerequisite for evaluating groundwater potential or underpinning aquifer sustainability development in hydrogeological engineering practices. This study explores the dominant influencing factors that control groundwater dynamics and develops an estimation of groundwater level fluctuation (GWLF) potential in ... A combination of a place to put water (porosity) and the ability to move water (permeability) makes a good aquifer—a rock unit or sediment that contains extractable groundwater. Well-sorted sediments have higher porosity because there are not smaller sediment particles filling in the spaces between the larger particles.Porosity, permeability, specific yield and specific retention are important properties of groundwater flow. Porosity is the volume of pore space relative to the total volume (rock and/or sediment + pore space). Primary porosity (% pore space) is the initial void space present (intergranular) when the rock formed. March 1, 2016. This paper presents results of hydrochemical and isotopic analyses of groundwater (fracture water) and porewater, and physical property and water content measurements of bedrock core at the Chalk River Laboratories (CRL) site in Ontario. Density and water contents were determined and water-loss porosity values were calculated for ...An aquifer is a body of porous rock or sediment saturated with groundwater. Groundwater enters an aquifer as precipitation seeps through the soil.Jun 28, 2018 · Water moving below ground depends on the permeability (how easy or difficult it is for water to move) and on the porosity (the amount of open space in the material) of the subsurface rock. If the rock has characteristics that allow water to move relatively freely through it, then groundwater can move significant distances in a number of days. 8.2 Determining Groundwater Flow Directions When evaluating the direction of groundwater flow, the first step is to plot the head data on a map or cross section, then create contours of equal head, i.e., equipotential lines, as shown in Figure 64 and Figure 65.Representations in cross-sectional views are created using axes that are equally …

The typical sequence for groundwater dispersion modeling is to perform Darcy Flow, then Particle Track, then Porous Puff. An example of the settings to make in the tool dialog box for Darcy Flow follows: Input groundwater head raster: head. Input effective formation porosity raster: poros. Input saturated thickness raster: thickn

When the curing age reaches 28 days, the porosity of gangue and tailing cemented backfill without bentonite is 38.41% (C-CaB0) and 47.57% (T-CaB0), respectively, and the porosity of tailing cemented backfill is much higher than that of gangue cemented backfill. The particle size mainly derived from tailings is much smaller than that of gangue.The rate of groundwater flow is controlled by two properties of the rock: porosity and permeability. Porosity is the percentage of the volume of the rock that is open space (pore space).Preferential air flow into the Quaternary Sands or groundwater variations in the sands could create driving pressures for gas flow into boreholes and/or the BF material. However, the BF and CSB have a relatively low permeability which will limit advective flow. The porosity of the BF is also low which will limit the rate of diffusive flow.Groundwater is water found below the water table in the zone of saturation within the pores and cracks of a wide variety of earth materials. Groundwater occurrence in porous material is described in terms of total porosity, effective porosity, void ratio, volumetric moisture content, specific yield, and specific retention.Groundwater is a primary agent of chemical weathering and is responsible for the formation of caves and sinkholes. The Groundwater System. Groundwater resides in the void spaces of rock, sediment, or soil, completely filling the voids. The total volume of open space in which the groundwater can reside is porosity. Porosity determines the amount ...Ultra-deep buried underground rail transit in coastal cities means that such projects will be under the groundwater level for a long time and face the impact of high hydraulic pressure up to 1.0 MPa or even higher. ... The porosity of ITZs of aggregates in specimens S5(a), S6(b), S7(c), S8(d), S9(e), S10(f), S11(g) and S12(h) under different ...Groundwater moves significantly slower than surface water. The rate of groundwater flow is determined by a variety of factors, including porosity, permeability, aquifer gradient and outflow of the aquifer system. Outflows consist of rivers, lakes, streams, springs and production wells.Groundwater is the largest reservoir of liquid fresh water on Earth and is found in aquifers, porous rock and sediment with water in between. Water is attracted to the soil particles and capillary action, which describes how water moves through a porous media, moves water from wet soil to dry areas. Aquifers are found at different depths.Noah-MP, this time with the simple groundwater module (SIMGM, Niu et al., 2007), employs an empirical value fixed at 0.2 in deep water table situations (where the water level is below the soil column), and uses the effective porosity, which is the volume of air pore space within the soil (Niu et al., 2007), to represent the specific yield in ...10 Exercises. 1) A 100 cubic centimeter (cm 3) sample of soil has an initial weight of 227.1 grams. It is oven dried at 105°C to a constant weight of 222.0 grams. The sample is then saturated with water and has a weight of 236.6 grams. Next, the sample is then allowed to drain by gravity in an environment of 100% humidity and is reweighted at ...

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Apr 28, 2022 · n e = Effective porosity - fraction of cross section available for groundwater flow (unitless) Effective porosity is smaller than total porosity. The difference is that total porosity includes some dead-end pores that do not support groundwater. Typical values for total and effective porosity are shown in Table 1. where V is the velocity of the groundwater, and n is the porosity (expressed as a proportion, so if the porosity is 10%, n = 0.1). We can apply this equation to the scenario in Figure 14.2.1. If we assume that the hydraulic conductivity is 0.00001 metres per second (m/s), we get q = 0.00001 × 0.08 = 0.0000008 m 3 per second per m 2. If the ... Unconsolidated sand and gravel aquifers are characterized by intergranular porosity and all contain water primarily under unconfined, or water-table, conditions. They are grouped into four categories: basin-fill, blanket sand and gravel, glacial-deposit, and stream-valley aquifers. ... The speed at which groundwater flows depends on the size of ...Ground Water Section Illinois Department of Energy and Natural Resources SWS Contract Report 351 EFFECTIVE POROSITY OF GEOLOGIC MATERIALS FIRST ANNUAL REPORT by James P. Gibb, Michael J. Barcelona. Joseph D. Ritchey, and Mary H. LeFaivre Champaign, Illinois September 1984Groundwater is the largest reservoir of fresh water. The water table is the top of an aquifer below which is water and above is rock or soil mixed with air. Aquifers are underground areas of sediment or rock that hold groundwater. An aquifer needs good porosity and permeability. Where groundwater intersects the ground surface, a spring can form.Ground water flow is much slower than flow in streams and rivers. That is because the passageways through the pore spaces are very small, so there is a lot of friction with the solid walls of the pores. Speeds of flow in streams and rivers are often greater than a meter per second. Ground water flow is often as slow as meters per day.Groundwater exists everywhere there is porosity. However, whether that groundwater is able to flow in significant quantities depends on the permeability. An aquifer is defined as a body of rock or unconsolidated sediment that has sufficient permeability to allow water to flow through it.Groundwater occurs mostly in unconfined or semiconfined conditions in the primary porosity. Groundwater is the only source for irrigation water. Soils of Jhunjhunu district are sandy to loamy sand, non-calcareous, structure less, loose, and well drained (CGWB, 2008).The saturated zone has a higher porosity than the unsaturated zone. B. ... Groundwater moves from areas where the water table is low to areas where the water table is ...The stage of ground water development for the country as a whole is 58%. The status of ground water development is comparatively high in the states of Delhi, Haryana, Punjab and Rajasthan and UT of Daman & Diu and Pondicherry, where the Stage of Ground Water Development is more than 100%, which implies that in these states the average annual … ….

The term ‘drainable porosity’ is defined as “the volume of water drained by gravity per unit volume of the saturated soil”. It is also called ‘effective porosity’ or ‘specific yield’ or ‘storage coefficient’, especially in groundwater hydrology or hydrogeology.But it is relatively porous and therefore contains water. Its porosity is between about 1 and 10%, i.e. one cubic metre of rock contains 10 to 100 litres of water; for a thickness of 30 m, there are 300 to 3000 litres of water under each m 2. This part of the alteration profile provides groundwater storage;Effective porosity is the space available for fluid to flow, and is calculated as the volume of interconnected void space to the total volume, typically given as a percentage. Porosity can be deemed either primary or secondary. Void spaces in primary porosity formed at the time the geologic material was created.These rocks are very hard and compact, and the groundwater occurs mainly in secondary porosity. Groundwater occurs under semiconfined to confined conditions in fractured rocks. Granite Gneisses are the most predominant rock types usually occupying the underlying plains and topographic lows. These rocks are highly …Used in hydrogeology, the groundwater flow equation is the mathematical relationship which is used to describe the flow of groundwater through an aquifer. ... Where n is the aquifer porosity. The source term, N (length per time), represents the addition of water in the vertical direction (e.g., recharge).GeoTutor: Groundwater and the Water Cycle Part B - The Groundwater Cycle When water winds up underground, it becomes part of the groundwater cycle.Water can only be present underground in areas where rocks have porosity—spaces or voids within the rock material. Well-rounded coarse-grained sediments usually have higher porosity. 1) ground surface intersects the water table in a discharge area (valley floors) 2) flowing groundwater collides with a steep, impermeable barrier (fault), and pressure pushes it up to the ground along the barrier. 3) perched water table intersects the surface of a hill. 4) downward-percolating water runs into a relatively impermeable layer and ...21 Mar 2023 ... Groundwater storage either between grains of sediment or in solution cavities.10 Exercises. 1) A 100 cubic centimeter (cm 3) sample of soil has an initial weight of 227.1 grams. It is oven dried at 105°C to a constant weight of 222.0 grams. The sample is then saturated with water and has a weight of 236.6 grams. Next, the sample is then allowed to drain by gravity in an environment of 100% humidity and is reweighted at ... Porosity groundwater, Groundwater is one of our most important natural resources. It supplies roughly a third of the water used in municipal water supplies across the nation, and supplies about 90 percent of drinking water used in rural communities that opt out of city water departments. Groundwater cleanup is very important in Alaska because many of our communities ..., The porosity of earth materials originates during two phases: 1) during the deposition of sediments, lithification or cooling of crystalline rock; and 2) after deposition as the earth material is exposed to other conditions such as compaction, weathering, fracturing and/or metamorphism. , Reading: Porosity and Permeability. Figure 1. A spring coming out of the shale near Red Creek. Yes, that water is black! (Photo: Matt Herod) As we’ve learned, groundwater is simply water that exists underground. However, there are still lots of misconceptions about how people envision groundwater. Many envision large underground lakes and ..., Dec 29, 2020 · Groundwater is water found below the water table in the zone of saturation within the pores and cracks of a wide variety of earth materials. Groundwater occurrence in porous material is described in terms of total porosity, effective porosity, void ratio, volumetric moisture content, specific yield, and specific retention. , Groundwater is the largest reservoir of fresh water. The water table is the top of an aquifer below which is water and above is rock or soil mixed with air. Aquifers are underground areas of sediment or rock that hold groundwater. An aquifer needs good porosity and permeability. Where groundwater intersects the ground surface, a spring can form., The boundary between the saturated zone and the unsaturated zone is called the______ . water table aquifer aquiclude porosity. The infiltration of water into ..., MODFLOW is a groundwater modelling program. It can be compiled and remedied according to the practical applications. Because structure and fixed data format, MODFLOW can be integrated with geographic information system (GIS) for ground water resource management. Groundwater is a distinguished component of the hydrologic …, Figure Box 2-3 – Areas used to calculate specific discharge and average linear velocity: a) specific discharge is defined as the volumetric flow rate divided by the total cross-section area (shown in gray); b) porosity includes all pore spaces as shown in blue; c) average linear velocity is higher than specific discharge because it accounts for only the area of groundwater flow through ..., Ground Water 69-94 Ground Water Occurrence and Resources Well Irrigation Well ... Porosity is dependent on soil texture and soil structure. Soil texture is decided by its particle size, for example clayey soils have clay particles, (smaller in size than 0.002 mm), ..., generally, the deeper the well the smaller the porosity and permeability of the medium, and so the lower the rate of flow into the well; The slower the flow into the well, the longer the residence time of the groundwater in the porous medium, so the longer the time available for uptake of ions from the medium, so the harder the water., Noah-MP, this time with the simple groundwater module (SIMGM, Niu et al., 2007), employs an empirical value fixed at 0.2 in deep water table situations (where the water level is below the soil column), and uses the effective porosity, which is the volume of air pore space within the soil (Niu et al., 2007), to represent the specific yield in ..., The stage of ground water development for the country as a whole is 58%. The status of ground water development is comparatively high in the states of Delhi, Haryana, Punjab and Rajasthan and UT of Daman & Diu and Pondicherry, where the Stage of Ground Water Development is more than 100%, which implies that in these states the average annual …, Water exists in significant amounts below just about Earth's entire surface. Below are your responses to our groundwater true/false quiz, and some explanations to help make you more groundwater knowledgeable. (1) The water table is the altitude (below ground) where the water level in a well will rise to when the well taps a confined aquifer., An aquifer is a body of porous rock or sediment saturated with groundwater. Groundwater enters an aquifer as precipitation seeps through the soil., The surface area and porosity of the nanocomposite were measured quantitatively using nitrogen adsorption BET. The samples were degassed at 150 °C for 48 h before recording N 2 adsorption-desorption isotherms at 77 K (−196 °C). The BET surface area and porosity (i.e., pore volume and pore size) of NiO/Ag/TiO 2 and TiO 2 are listed in Table 1., FEATURES ASSOCIATED WITH GROUNDWATER. POROSITY and PERMEABLILITY. POROSITY: percentage of "empty" space (pores) in a rock or sediment. PERMEABILITY: ability of ..., These minerals form as a result of precipitation or mineral alteration during groundwater circulation through the sand. Compaction is important at great depth, where temperatures and pressures are high. Studies by Chilingar (1963), Maxwell (1964), and Atwater (1966) show that the porosity of sandstone decreases systematically with depth., Relatively large-scale or bulk processes of groundwater flow phenomena in a fractured porous medium can be described by adopting the dual porosity groundwater model. To analyze groundwater flow with the dual porosity model, relevant hydraulic parameters must be determined. Laboratory experiments or field well tests can be applied to …, Adsorption, degradation, and movement are the key processes conditioning the behavior and fate of pesticides in the soil. Six processes that can move pesticides are leaching, diffusion, volatilization, erosion and run-off, assimilation by microorganisms, and plant uptake. Leaching is the vertical downward displacement of pesticides through the …, Ground Water Section Illinois Department of Energy and Natural Resources SWS Contract Report 351 EFFECTIVE POROSITY OF GEOLOGIC MATERIALS FIRST ANNUAL REPORT by James P. Gibb, Michael J. Barcelona. Joseph D. Ritchey, and Mary H. LeFaivre Champaign, Illinois September 1984 , Preferential air flow into the Quaternary Sands or groundwater variations in the sands could create driving pressures for gas flow into boreholes and/or the BF material. However, the BF and CSB have a relatively low permeability which will limit advective flow. The porosity of the BF is also low which will limit the rate of diffusive flow., Ancient groundwater can take thousands of years to replenish naturally. And, as California saw during its 2011-2017 drought, natural underground storage spaces compress as they empty, so they can ..., What is the difference between a confined and unconfined aquifer? What is porosity and does it influence groundwater resources? We then explain and apply ..., from parent minerals, as particle size decreases, and as porosity increases. These studies will help to elucidate the surface area term necessary to better inform reactive transport models of shale-based soils. ... groundwater contamination David Kargbo(1), [email protected], 1947 N. 12th Street, Room 730, Philadelphia PA, United States ., The isoresistivity maps showing resistivity distribution of the aquifer layers (weathered layer, weathered basement, and basement) had proven useful in promising mapping areas for groundwater abstraction. The porosity of the subsurface materials in the study area also helps in delineating the aquifer since the saturated zone of the aquifer area ..., Nov 21, 2000 · Groundwater Storage and Flow R. W. Buddemeier, J. A. Schloss Boldface items are linked to other sections; italic items are linked to glossary definitions. Groundwater Storage, Porosity, and Specific Yield: Groundwater occupies the cracks and pore spaces between rocks and mineral grains below the land surface. In the saturated zone, essentially ... , Porosity (usually denoted by the symbol η, which is Greek letter 'eta') is the primary aquifer property that controls water storage, and is defined as the ..., These minerals form as a result of precipitation or mineral alteration during groundwater circulation through the sand. Compaction is important at great depth, where temperatures and pressures are high. Studies by Chilingar (1963), Maxwell (1964), and Atwater (1966) show that the porosity of sandstone decreases systematically with depth., Groundwater Temperature's Measurement and Significance. Oscar E. Meinzer's discussion of the occurrence of groundwater in the United States (1923, The Occurrence of Ground Water in the U.S. with a Discussion of Principles, USGS Water-Supply Paper 489) is a classic in the science of groundwater and geology. It is an excellent reference for the ..., Porosity that is not considered "effective porosity" includes water bound to clay particles (known as bound water) and isolated "vuggy" porosity (vugs not connected to other …, 30 Kas 2017 ... ... porosity; 22. Figure: Relation Between Texture and Porosity ○ Well –Sorted Sand Having High Porosity ○ Poorly- Sorted Sand Having Low Porosity ..., Corrected groundwater 14C ages from the carbonate aquifer in Yucca Flat at the former Nevada Test Site (now the Nevada National Security Site), USA, were evaluated by comparing temporal variations of groundwater 36Cl/Cl estimated with these 14C ages with published records of meteoric 36Cl/Cl variations preserved in packrat middens (piles …, a. Porosity is the primary governing factor influencing the ability of rock or sediment to store fluids (e.g. groundwater or hydrocarbons) b. Types of Porous Openings (a) Intergranular Porosity = primary pore spaces present between particles of a sediment or rock deposit i) Intergranular Porosity influenced by: a) sorting b) grain packing c ...