Maliheh Pourali | Ferdowsi University of Mashhad (original) (raw)
Papers by Maliheh Pourali
Spatial Information Research, Nov 30, 2019
Investigation of geomorphic indices is a useful approach to identify the specific characteristics... more Investigation of geomorphic indices is a useful approach to identify the specific characteristics of active tectonics in each region. In this study, five geomorphic indices including stream length-gradient index, basin asymmetry, hypsometric integral, ratio of valley-floor width, and index of basin shape were estimated to assess relative active tectonics in the Band-Golestan basin, as a part of Binaloud mountainous zone, located in northeastern Iran. This region includes several faults, formed mainly by contact, fraction, and re-crystallization processes between shale and sandstone rocks. An average index of the active tectonics was produced to categorize the intensity classes of tectonic activity of the study area. According to the mean values of indices, the whole basin has active or semi-active tectonics. After that, the overall index of Iat with a value of 1.88 indicated the high class of tectonic activity for the study area. Furthermore, the obtained result of tectonic activity was confirmed by fieldwork and previous literature. In this regard, the active tectonics of the study area has corresponded to the highest values of sediment yield, soil losses, dynamic failures, and various types of landslide events.
Carbonates and Evaporites
This study aims to investigate Sabzevar playa in the northeast of the Great Kavir in terms of geo... more This study aims to investigate Sabzevar playa in the northeast of the Great Kavir in terms of geomorphology, bulk and clay mineralogy, as well as the geochemistry of core sediments from the surface to a depth of 1 m. The results suggest that up to 50% of Sabzevar playa is made of clastic components (mostly quartz and clay minerals), which increases toward the depth, though this trend is bucked by evaporite minerals (mostly gypsum, calcium carbonate, and halite). According to the mineralogical trend and geochemical evidence, Sabzevar brine has evolved into a Na-SO 4-Cl type. Granulometry studies suggest drastic fluctuations and higher energy costs during sediment deposition at a depth of 1 m compared to the surface. The micro-morphology of quartz grains is due to the windborne surface sediments and waterborne deep grains. A combination of clay mineralogy and geochemistry of elements exhibits a higher evaporation rate at the surface than at a depth of 1 m, suggesting that the area has witnessed a climate change from a warm humid climate in the past to a warm arid climate in recent years. Sabzevar playa is characterized by an unconventional Bull's-eye pattern with a concentration of calcite around the playa, gypsum in the center, and halite in the west. This research also explores the hydrological characteristics of the study area based on geomorphologic surfaces findings revealing that the groundwater level was higher in the west than in the center and east of Sabzevar playa, leading to the formation of halite and the development of a salt pan in the margin.
Journal of Arid Regions Geographics Studies, Sep 10, 2020
2nd International Conference on Quaternary Sciences, Sep 5, 2021
The 1st international and 3rd national symposium of Iran Quaternary, Feb 13, 2018
We studied mineral and deposition records in a dry lake playa, Sabzevar, northeastern, Iran. For ... more We studied mineral and deposition records in a dry lake playa, Sabzevar, northeastern, Iran. For sampling soil and depositional records, 12 samples were taken along Playa surfaces including firm puffy ground, clay-carbonate plain, and salty pan with the dominance of Halite salts. All profiles were excavated by hand auger with a 5 cm diameter head to a depth of ~5 cm. Sediment analysis was carried out through soil physicochemical properties and XRD/XRF were done for mineralogy. According to the XRF results, main minerals of quartzite and calcite are observed over the playa. After XRD results, the major minerals in the sediments were categorized as quartzite, halite, calcite, and gypsum. Afterward, the minerals of halite, calcite, gypsum indicate dominant evaporate process. Enrichment of evaporate minerals on the surface grounds are an evidence of a variation hydrostatic level of Sabzevar playa, which can be a signal for a wet lake in the past and dried one in the present day.
The depositional pattern of dry lake playa sediments in NE Iran was studied to characterize the s... more The depositional pattern of dry lake playa sediments in NE Iran was studied to characterize the surface morphology of the playa based on sediment mineralogy. About 12 topo-soil samples were excavated by hand auger. All topo-soils were collected in three landforms of firm-puffy ground, clay-carbonate crusts, and halite dominated saltpans, to be examined for mineralogy by XRD analysis and physicochemical properties in the lab. XRF analysis performed to define the major oxides of the sediments. Quartz and calcite were the main minerals over the playa. Also, halite and gypsum were the major minerals categorized in the sediments indicating the dominant evaporate process in the area. Based on the results, a high concentration of EC (>48 dS/m) was observed in the mid-southern and southern part of the playa. Besides, the high concentrations of CCE (>27 %) and pH (>9) were observed in the eastern and the western playa, verifying the primary detection of the playa’s three major geomo...
Spatial Information Research, 2019
Investigation of geomorphic indices is a useful approach to identify the specific characteristics... more Investigation of geomorphic indices is a useful approach to identify the specific characteristics of active tectonics in each region. In this study, five geomorphic indices including stream length-gradient index, basin asymmetry, hypsometric integral, ratio of valley-floor width, and index of basin shape were estimated to assess relative active tectonics in the Band-Golestan basin, as a part of Binaloud mountainous zone, located in northeastern Iran. This region includes several faults, formed mainly by contact, fraction, and re-crystallization processes between shale and sandstone rocks. An average index of the active tectonics was produced to categorize the intensity classes of tectonic activity of the study area. According to the mean values of indices, the whole basin has active or semi-active tectonics. After that, the overall index of Iat with a value of 1.88 indicated the high class of tectonic activity for the study area. Furthermore, the obtained result of tectonic activity was confirmed by fieldwork and previous literature. In this regard, the active tectonics of the study area has corresponded to the highest values of sediment yield, soil losses, dynamic failures, and various types of landslide events.
Sustainable Water Resources Management, 2015
In this research, the hydrogeochemical and geomorphological evidences of travertine deposition we... more In this research, the hydrogeochemical and geomorphological evidences of travertine deposition were investigated to detect the Garab Spring region as a unique travertine zone of northeastern Iran. Some of the hydrological and geochemical properties of the water and rocks were analyzed. According to the concentration of major components, the chemical property of the Garab Spring water was identified as Na-Cl and Ca-HCO 3-SO 4. Based on the geochemical results of XRF, the most important compositions of the rock samples were demonstrated as CaO, Fe 2 O 3 and MgO with 59.24, 8.78 and 7.14 %, respectively. The petrography analysis indicated calcite mineralogy. Furthermore, the geomorphological shapes of the rocks were categorized into both robust travertine and fragile tufa.
Desert Ecosystem Engineering Journal, 2020
The depositional pattern of dry lake playa sediments in NE Iran was studied to characterize the s... more The depositional pattern of dry lake playa sediments in NE Iran was studied to characterize the surface morphology of the playa based on sediment mineralogy. About 12 topo-soil samples were excavated by hand auger. All topo-soils were collected in three landforms of firm-puffy ground, clay-carbonate crusts, and halite dominated saltpans, to be examined for mineralogy by XRD analysis and physicochemical properties in the lab. XRF analysis performed to define the major oxides of the sediments. Quartz and calcite were the main minerals over the playa. Also, halite and gypsum were the major minerals categorized in the sediments indicating the dominant evaporate process in the area. Based on the results, a high concentration of EC (>48 dS/m) was observed in the mid-southern and southern part of the playa. Besides, the high concentrations of CCE (>27 %) and pH (>9) were observed in the eastern and the western playa, verifying the primary detection of the playa's three major geomorphologic landforms in the fieldwork. A recent depositional pattern of carbonates and chloride formed from eastern to the western parts of the playa, respectively. Nevertheless, central playa shows the areas with the main minerals of calcite and halite. The existence of evaporate minerals depends on a cycle of the wet and dried lake during the Holocene.
2nd International Conference on Quaternary Sciences, 2021
The Quaternary period was characterized by drastic changes in climatic conditions worldwide (Roy... more The Quaternary period was characterized by drastic changes in climatic conditions
worldwide (Roy et al., 2006) so that the escalation of eolian processes, desert formation and drying of
lakes are attributed to this period (Koutavas et al., 2002). Playa is a region with negative water balance
for more than half a year as well as capillary properties close to the surface and sediments (Rosen, 1994).
In some cases, playa sediments are the only evidence of past environmental conditions in arid and semi-
arid regions (Davis, 1994). Clay minerals are one of main proxies for paleoenvironment and paleoclimate
studies (Thiry, 2000). Also, changes in clay minerals in sediments are often indicative of climate changes
(Birks et al, 2012). The analysis of clay plains in playas and dried pluvial lake provides a good criterion for
determining the origin of sediments and climate change (Oliveira et al, 2002); (Battarbee, 1999). Hence,
some researchers (Bentz, 2017), (Jones, 1983), (Srodon, 1997), (Tateo et al., 2000), (Kadir et al., 2016
DeVogel et al., 2004) have conducted valuable studies on late Quaternary climate changes using clay
minerals. The present study aims to reconstruct the late Quaternary climate based on clay minerals
obtained from Sabzevar Playa in northeastern Iran.
Carbonates and Evaporites, 2023
This study aims to investigate Sabzevar playa in the northeast of the Great Kavir in terms of geo... more This study aims to investigate Sabzevar playa in the northeast of the Great Kavir in terms of geomorphology, bulk and clay mineralogy, as well as the geochemistry of core sediments from the surface to a depth of 1 m. The results suggest that up to 50% of Sabzevar playa is made of clastic components (mostly quartz and clay minerals), which increases toward the depth, though this trend is bucked by evaporite minerals (mostly gypsum, calcium carbonate, and halite). According to the mineralogical trend and geochemical evidence, Sabzevar brine has evolved into a Na-SO 4-Cl type. Granulometry studies suggest drastic fluctuations and higher energy costs during sediment deposition at a depth of 1 m compared to the surface. The micro-morphology of quartz grains is due to the windborne surface sediments and waterborne deep grains. A combination of clay mineralogy and geochemistry of elements exhibits a higher evaporation rate at the surface than at a depth of 1 m, suggesting that the area has witnessed a climate change from a warm humid climate in the past to a warm arid climate in recent years. Sabzevar playa is characterized by an unconventional Bull's-eye pattern with a concentration of calcite around the playa, gypsum in the center, and halite in the west. This research also explores the hydrological characteristics of the study area based on geomorphologic surfaces findings revealing that the groundwater level was higher in the west than in the center and east of Sabzevar playa, leading to the formation of halite and the development of a salt pan in the margin.
Conference Presentations by Maliheh Pourali
3rd International Conference and 6th National Conference of Quaternary Sciences, 2024
Spatial Information Research, Nov 30, 2019
Investigation of geomorphic indices is a useful approach to identify the specific characteristics... more Investigation of geomorphic indices is a useful approach to identify the specific characteristics of active tectonics in each region. In this study, five geomorphic indices including stream length-gradient index, basin asymmetry, hypsometric integral, ratio of valley-floor width, and index of basin shape were estimated to assess relative active tectonics in the Band-Golestan basin, as a part of Binaloud mountainous zone, located in northeastern Iran. This region includes several faults, formed mainly by contact, fraction, and re-crystallization processes between shale and sandstone rocks. An average index of the active tectonics was produced to categorize the intensity classes of tectonic activity of the study area. According to the mean values of indices, the whole basin has active or semi-active tectonics. After that, the overall index of Iat with a value of 1.88 indicated the high class of tectonic activity for the study area. Furthermore, the obtained result of tectonic activity was confirmed by fieldwork and previous literature. In this regard, the active tectonics of the study area has corresponded to the highest values of sediment yield, soil losses, dynamic failures, and various types of landslide events.
Carbonates and Evaporites
This study aims to investigate Sabzevar playa in the northeast of the Great Kavir in terms of geo... more This study aims to investigate Sabzevar playa in the northeast of the Great Kavir in terms of geomorphology, bulk and clay mineralogy, as well as the geochemistry of core sediments from the surface to a depth of 1 m. The results suggest that up to 50% of Sabzevar playa is made of clastic components (mostly quartz and clay minerals), which increases toward the depth, though this trend is bucked by evaporite minerals (mostly gypsum, calcium carbonate, and halite). According to the mineralogical trend and geochemical evidence, Sabzevar brine has evolved into a Na-SO 4-Cl type. Granulometry studies suggest drastic fluctuations and higher energy costs during sediment deposition at a depth of 1 m compared to the surface. The micro-morphology of quartz grains is due to the windborne surface sediments and waterborne deep grains. A combination of clay mineralogy and geochemistry of elements exhibits a higher evaporation rate at the surface than at a depth of 1 m, suggesting that the area has witnessed a climate change from a warm humid climate in the past to a warm arid climate in recent years. Sabzevar playa is characterized by an unconventional Bull's-eye pattern with a concentration of calcite around the playa, gypsum in the center, and halite in the west. This research also explores the hydrological characteristics of the study area based on geomorphologic surfaces findings revealing that the groundwater level was higher in the west than in the center and east of Sabzevar playa, leading to the formation of halite and the development of a salt pan in the margin.
Journal of Arid Regions Geographics Studies, Sep 10, 2020
2nd International Conference on Quaternary Sciences, Sep 5, 2021
The 1st international and 3rd national symposium of Iran Quaternary, Feb 13, 2018
We studied mineral and deposition records in a dry lake playa, Sabzevar, northeastern, Iran. For ... more We studied mineral and deposition records in a dry lake playa, Sabzevar, northeastern, Iran. For sampling soil and depositional records, 12 samples were taken along Playa surfaces including firm puffy ground, clay-carbonate plain, and salty pan with the dominance of Halite salts. All profiles were excavated by hand auger with a 5 cm diameter head to a depth of ~5 cm. Sediment analysis was carried out through soil physicochemical properties and XRD/XRF were done for mineralogy. According to the XRF results, main minerals of quartzite and calcite are observed over the playa. After XRD results, the major minerals in the sediments were categorized as quartzite, halite, calcite, and gypsum. Afterward, the minerals of halite, calcite, gypsum indicate dominant evaporate process. Enrichment of evaporate minerals on the surface grounds are an evidence of a variation hydrostatic level of Sabzevar playa, which can be a signal for a wet lake in the past and dried one in the present day.
The depositional pattern of dry lake playa sediments in NE Iran was studied to characterize the s... more The depositional pattern of dry lake playa sediments in NE Iran was studied to characterize the surface morphology of the playa based on sediment mineralogy. About 12 topo-soil samples were excavated by hand auger. All topo-soils were collected in three landforms of firm-puffy ground, clay-carbonate crusts, and halite dominated saltpans, to be examined for mineralogy by XRD analysis and physicochemical properties in the lab. XRF analysis performed to define the major oxides of the sediments. Quartz and calcite were the main minerals over the playa. Also, halite and gypsum were the major minerals categorized in the sediments indicating the dominant evaporate process in the area. Based on the results, a high concentration of EC (>48 dS/m) was observed in the mid-southern and southern part of the playa. Besides, the high concentrations of CCE (>27 %) and pH (>9) were observed in the eastern and the western playa, verifying the primary detection of the playa’s three major geomo...
Spatial Information Research, 2019
Investigation of geomorphic indices is a useful approach to identify the specific characteristics... more Investigation of geomorphic indices is a useful approach to identify the specific characteristics of active tectonics in each region. In this study, five geomorphic indices including stream length-gradient index, basin asymmetry, hypsometric integral, ratio of valley-floor width, and index of basin shape were estimated to assess relative active tectonics in the Band-Golestan basin, as a part of Binaloud mountainous zone, located in northeastern Iran. This region includes several faults, formed mainly by contact, fraction, and re-crystallization processes between shale and sandstone rocks. An average index of the active tectonics was produced to categorize the intensity classes of tectonic activity of the study area. According to the mean values of indices, the whole basin has active or semi-active tectonics. After that, the overall index of Iat with a value of 1.88 indicated the high class of tectonic activity for the study area. Furthermore, the obtained result of tectonic activity was confirmed by fieldwork and previous literature. In this regard, the active tectonics of the study area has corresponded to the highest values of sediment yield, soil losses, dynamic failures, and various types of landslide events.
Sustainable Water Resources Management, 2015
In this research, the hydrogeochemical and geomorphological evidences of travertine deposition we... more In this research, the hydrogeochemical and geomorphological evidences of travertine deposition were investigated to detect the Garab Spring region as a unique travertine zone of northeastern Iran. Some of the hydrological and geochemical properties of the water and rocks were analyzed. According to the concentration of major components, the chemical property of the Garab Spring water was identified as Na-Cl and Ca-HCO 3-SO 4. Based on the geochemical results of XRF, the most important compositions of the rock samples were demonstrated as CaO, Fe 2 O 3 and MgO with 59.24, 8.78 and 7.14 %, respectively. The petrography analysis indicated calcite mineralogy. Furthermore, the geomorphological shapes of the rocks were categorized into both robust travertine and fragile tufa.
Desert Ecosystem Engineering Journal, 2020
The depositional pattern of dry lake playa sediments in NE Iran was studied to characterize the s... more The depositional pattern of dry lake playa sediments in NE Iran was studied to characterize the surface morphology of the playa based on sediment mineralogy. About 12 topo-soil samples were excavated by hand auger. All topo-soils were collected in three landforms of firm-puffy ground, clay-carbonate crusts, and halite dominated saltpans, to be examined for mineralogy by XRD analysis and physicochemical properties in the lab. XRF analysis performed to define the major oxides of the sediments. Quartz and calcite were the main minerals over the playa. Also, halite and gypsum were the major minerals categorized in the sediments indicating the dominant evaporate process in the area. Based on the results, a high concentration of EC (>48 dS/m) was observed in the mid-southern and southern part of the playa. Besides, the high concentrations of CCE (>27 %) and pH (>9) were observed in the eastern and the western playa, verifying the primary detection of the playa's three major geomorphologic landforms in the fieldwork. A recent depositional pattern of carbonates and chloride formed from eastern to the western parts of the playa, respectively. Nevertheless, central playa shows the areas with the main minerals of calcite and halite. The existence of evaporate minerals depends on a cycle of the wet and dried lake during the Holocene.
2nd International Conference on Quaternary Sciences, 2021
The Quaternary period was characterized by drastic changes in climatic conditions worldwide (Roy... more The Quaternary period was characterized by drastic changes in climatic conditions
worldwide (Roy et al., 2006) so that the escalation of eolian processes, desert formation and drying of
lakes are attributed to this period (Koutavas et al., 2002). Playa is a region with negative water balance
for more than half a year as well as capillary properties close to the surface and sediments (Rosen, 1994).
In some cases, playa sediments are the only evidence of past environmental conditions in arid and semi-
arid regions (Davis, 1994). Clay minerals are one of main proxies for paleoenvironment and paleoclimate
studies (Thiry, 2000). Also, changes in clay minerals in sediments are often indicative of climate changes
(Birks et al, 2012). The analysis of clay plains in playas and dried pluvial lake provides a good criterion for
determining the origin of sediments and climate change (Oliveira et al, 2002); (Battarbee, 1999). Hence,
some researchers (Bentz, 2017), (Jones, 1983), (Srodon, 1997), (Tateo et al., 2000), (Kadir et al., 2016
DeVogel et al., 2004) have conducted valuable studies on late Quaternary climate changes using clay
minerals. The present study aims to reconstruct the late Quaternary climate based on clay minerals
obtained from Sabzevar Playa in northeastern Iran.
Carbonates and Evaporites, 2023
This study aims to investigate Sabzevar playa in the northeast of the Great Kavir in terms of geo... more This study aims to investigate Sabzevar playa in the northeast of the Great Kavir in terms of geomorphology, bulk and clay mineralogy, as well as the geochemistry of core sediments from the surface to a depth of 1 m. The results suggest that up to 50% of Sabzevar playa is made of clastic components (mostly quartz and clay minerals), which increases toward the depth, though this trend is bucked by evaporite minerals (mostly gypsum, calcium carbonate, and halite). According to the mineralogical trend and geochemical evidence, Sabzevar brine has evolved into a Na-SO 4-Cl type. Granulometry studies suggest drastic fluctuations and higher energy costs during sediment deposition at a depth of 1 m compared to the surface. The micro-morphology of quartz grains is due to the windborne surface sediments and waterborne deep grains. A combination of clay mineralogy and geochemistry of elements exhibits a higher evaporation rate at the surface than at a depth of 1 m, suggesting that the area has witnessed a climate change from a warm humid climate in the past to a warm arid climate in recent years. Sabzevar playa is characterized by an unconventional Bull's-eye pattern with a concentration of calcite around the playa, gypsum in the center, and halite in the west. This research also explores the hydrological characteristics of the study area based on geomorphologic surfaces findings revealing that the groundwater level was higher in the west than in the center and east of Sabzevar playa, leading to the formation of halite and the development of a salt pan in the margin.
3rd International Conference and 6th National Conference of Quaternary Sciences, 2024