Modern Geological Mapping Research Articles

The Cretaceous of the Spanish Central System: A review of the lithostratigraphy, palaeontology and sequence stratigraphy, including new educational perspectives

The Southern Cretaceous of the Central System is formed by both terrigenous and carbonate rocks that have been affected by intense dolomitization. They are part of the sediments deposited on the western margin of the Iberian Basin during the Cenomanian–Maastrichtian, the depositional architecture of which has been reconstructed through a detailed sequence stratigraphical study and analysis of its fossil record. It is formed by three large transgressive-regressive cycles in which the carbonate platform moves towards the West, while the terrigenous facies of its base decreases and the overlying clay facies, with gypsum, increases. The integration of sedimentological and palaeontological data, and the identification of a set of parasequences has allowed the differentiation of thirteen depositional sequences. This research has been essential to carry out modern geological mapping and provide society with a model that improves the economic geology and geotechnical exploration of these areas. Furthermore, this scientific progress has also impacted on the interest of society towards the geosciences and, specially, palaeontology. This has widened the scope for new research fields related to scientific outreach for the community and learning opportunities at different educational levels.

Geological map of Antony Karol Giedroyc of the territory of Lithuania in the context of geological cartography of the 19th century

The history of geological cartography of the present territory of Lithuania starts with a map published by Jean Etienne Guettard in 1764 and followed by maps by Stanisław Staszic in 1806, Ignacy Domeyko in 1837, and Frederic Dubois de Montpereaux in 1830. A new period of investigations and compilation of geological maps starts about 1840 and is closely related with the development of stratigraphic knowledge; therefore, this period marks the beginning of mapping using the stratigraphic concept (Helmersen 1841). The Geological Committee in St. Petersburg, founded in 1882, at the very beginning of its activities started the compilation of a geological map including the present territory of Lithuania. The works of Antony Karol Giedroyc (Antanas Karolis Giedraitis) were published in 1895 (Giedroyc 1895), and the volume included a map which displays the occurrences of Quaternary and Pre-Quaternary (Tertiary, Cretaceous, and Jurassic) sediments and rocks. The map is constructed on the basis of direct observations and descriptions of outcrops and exposures of Quaternary sediments and Pre-Quaternary rocks carried out by the author, also based on evidence by local people. The main occurrences (provinces) of Pre-Quaternary rocks mapped by Giedroyc are confirmed by the modern geological mapping of the 20th century; therefore, the map of Giedroyc (1895) is regarded as a pioneering work of modern geological mapping using international stratigraphic standards.

Magyarország első közepes méretarányú (M=1:144.000) földtani térképsorozata a XIX. század második feléből

A Magyar Királyi Állami Földtani Intézet és jogutódjai 150 éves történetük alatt Magyarország geológiai térképezésének legfontosabb bázisintézményei voltak. Az intézet történetének első rendszeres, közepes méretarányú földtani térképműve Magyarország (nem teljes) 1:144,000 méretarányú geológiai térképsorozata volt. A térképmű a Habsburg Birodalom második katonai felmérésének nyomtatott ún. részletes térképeit használta topográfiai alapként, amelyre kézi színezéssel vitték fel a földtani tartalom felületi jeleit. A térképmű több szelvénye két, néhány pedig három, különböző színezésben is megtalálható az intézet könyvtárában. Minthogy a térképmű készítése megelőzte, ill. részben egybeesett a nemzetközi földtani jelkulcsot egységesítő bolognai kongresszussal, egyik változat színei sem egyeznek meg a ma szokásossal. Megadjuk a térképmű georeferálásához szükséges metaadatokat, illetve egy mintaterületen (Balaton-felvidék) bemutatjuk az 1:144 000-es térképművön és a mai földtani alaptérképen ábrázolt bazalt-területek kiterjedésének eltérését.

Прогнозная геохимия рудного золота Восточного Забайкалья

The subject of the research is the methods of forecasting the Eastern Transbaikalia - a large mining region of Russia, in which the main internal and external criteria for ore content are established by modern geological mapping at a scale of 1:1,000,000. The article considers endogenous geochemical criteria for gold concentration in the Earth’s crust of the region, which constitute a mandatory methodological method for predicting gold ore objects at any scale. The aim of the work is to clarify the achieved level of knowledge about the mineralogical and geochemical criteria for gold concentration in the course of the evolution of the Earth’s crust up to the formation of industrial deposits and the isolation of ore formations. The methodology of the study is to systematize a huge amount of factual material concerning the processes of natural concentration of gold, to analyze its representativeness, to assess the completeness and reliability of published and stock information used to clarify the mineralogical and geochemical criteria for predicting ore gold. Using the chemical properties of gold, the forms of finding gold, amount of it in the forming geological complexes and natural environments, their evolution, distribution in structural and tectonic zones, some causes of concentration and mineralogical and geochemical prediction criteria are considered. Special attention is paid to the need to study and account for nanoscale (dispersed) gold. As the main ore-formation units of gold mineralization, standardized ore formations are defined with a division into gold ore proper, complex gold-bearing and gold-bearing and geological and industrial types of deposits. There are 15 geological and industrial types, of which 13 are transbaikal deposits standards and two are attracted from other regions. These types of deposits differ in the number of objects related to them. Due to some similarity in the composition of ore matter, geological and industrial types differ in the most important classification characteristics for the forecast. Areas of distribution of direct and indirect mineralogical and geochemical features grouped into mineralogical and geochemical forecast criteria are promising for endogenous concentration of gold mineralization

Geology of the Gobi Altai and Tseel terranes in the central part of the Sagsai River Watershed, SE Mongolian Altai

ABSTRACTA geological map is an indispensable tool for understanding the structure of the Earth’s crust but high-quality geological maps are usually lacking in remote areas of mountainous Central Asia covered by vast deserts. The progress in remote sensing and geographical information system (GIS), as well as the advancement in analytical methods, have generated new challenges in producing modern geological maps in such regions. The presented 1:50,000 geological map along the Sagsai River summarizes new and more accurate geological data from the geologically interesting region at the contact of the supracrustal and deep crustal Tugrug and Tseel units forming the metamorphosed accretionary wedge on the S and SW slopes of the Mongolian Altai. These geological units are formed by the lower Palaeozoic volcano-sedimentary sequences affected by Devonian Barrovian metamorphism ranging from lower greenschist to granulite facies. This metamorphic basement was subsequently intruded by the post-orogenic late Carboniferous Sagsai Pluton. The presented map shows complex relationships between different crustal levels of the metamorphosed accretionary wedge and post-tectonic intrusion evaluated using a GIS, numerical processing of remote sensing data as well as field documentation and laboratory studies.

空间遥感测绘光学系统研究综述

The application of remote sensing technology to the mapping is the development trend of modern geological mapping technology. With the increasing resolution of optical load,mapping remote sensor has become an important guarantee for social development and the development of the national economy. Optical load which is the core component of remote sensor determines the resolution of mapping space remote sensor,the precision of mapping,and the volume and weight of the satellite platform. Structure and optical properties of the mapping space remote sensor optical system are introduced,such as high image quality refractive system,co-axial three mirrors system and off-axial three mirrors system. Then,structure and optical properties of new space reflective optical system in development are prospected. Analysis result indicates that according to different application environment and technical index,different types of optical system should be selected reasonably,so the platform resources can be used fully to meet the demand of mapping remote sensor.

Geological cartography in Poland in the 19th century

The history of modern geological mapping in Poland began with the Carta Geologica totius Poloniae, Moldaviae, Transylvaniae, Hungariae et Valachiae by S. Staszic, often called the “father of Polish geology”. Before Staszic, a general map of Poland had been published by J.-E. Guettard (1764a); ones of the Sudety Mts. by J. Jirasek (1791), L. von Buch (1797), and Raumer (1813); and that of the Tatra Mts. by Hacquet (1796). In times of the partition of Poland (1772 to 1918), areas annexed by Prussia were covered by systematic geological surveys. These cartographic projects resulted in the compilation of two geological atlases comprising maps of the standard sheet type, in the period from 1826 to 1836. These atlases were compiled by teams of outstanding geologists, under the leadership of L. von Buch and F. Hoffmann. Another outstanding contribution to the geology of Poland was made by G.G. Pusch, the author of the excellent Geognostische Beschreibung von Polen (1833–1836), subsequently supplemented by Geognostyscher Atlas von Polen. One of the greatest achievements of L. Zejszner was the geological map of the Tatra Mts., Carte de la chaine du Tatra , published anonymously in Berlin in 1844, and a series of geological maps prepared as drafts of Geognostic maps of the Eastern District of the Polish Kingdom. Special attention should be also paid to two extensive studies which covered areas of Upper and Lower Silesia. The first of these, Geognostische Karte von Oberschlesien und den Angrenzenden Gebieten , was completed by a team led by F. Roemer, and published in 1870. The second, Geologische Karte von dem Niederschlesischen Gebirge und den angrezenden gegenden , was compiled by a team led by R. von Carnall, and published in the same year. Out of all the studies carried out by Austrian geologists, it is necessary to mention those of E. Tietze, as they produced excellent geological maps of the Carpathians and vicinities of Krakow and Lviv. It is also worth mentioning the contributions made by the Physiographic Commission, active from 1866 until the beginning of the First World War. Its members decided to prepare the Geological Atlas of Galicia . The final product of works of this commission was a set of 25 booklets, with over a hundred geological maps at a scale 1:75000, issued in the years 1885–1912. From 1881, the commission was also publishing its famous Physiographic Diaries , which include papers on the geology of areas annexed by Russia, written by famous Polish geologists such as J. Siemiradzki, A. Michalski, and E. Habdank-Dunikowski, illustrated with relevant geological maps prepared by them.

Improving digital tools for Quaternary field survey: a case study of the Rodoretto Valley (NW Italy)

In the modern geological mapping activities geomatics technologies can facilitate data collection during field survey and avoid practical problems related to the transposition of that data onto topographic maps. This paper describes an innovative tool (the Solid True OrthoPhoto; STOP) for the structured acquisition and recording of geological field survey data that is immediately available in a GIS framework. An experimental software graphical interface has been developed to manage the STOP application during the survey. The benefits of the STOP system were tested by producing a digital map of the Quaternary formations and landforms in a 3-km2 sector of the Rodoretto Valley, a minor tributary of the Germanasca Valley, northwestern Italy.

Modern geological mapping and subsurface lithostratigraphic setting of the Venice Lagoon (Italy)

In the last decade, the knowledge of the Late Pleistocene and Holocene morphostratigraphic setting and geological evolution of the Venice lagoon area (north-western Adriatic Sea, Italy) has largely improved thanks to the analysis of new data from cores and the interpretation of a large number of very high resolution seismic (VHRS) profiles acquired in the Lagoon and Gulf of Venice. With reference to this topic, the Sheet 128 “Venezia” and the Sheet 148–149 “Chioggia-Malamocco” of the new Geological Map of Italy at the 1:50,000 scale (Carta Geologica d’Italia alla scala 1:50.000) represent the most important geological synthetic documents realized in the last years. They show age, distribution, sedimentological characteristics, and depositional environments of the exposed and buried sedimentary bodies, classified using the unconformity-bounded stratigraphic units. The analysis of data from deep cores, supported by the interpretation of VHRS profiles acquired along channels, has allowed the identification of the stratigraphic setting of the Venice lagoon subsoil generally down to about 30 m from the ground surface, and the reconstruction of the Late Pleistocene and Holocene evolution of the study area. More recently, a new VHRS system, implemented for investigations in water depth <1 m, has provided clear images of the subsurface also in the lagoon shallows; consequently, it has allowed the acquisition of new information about depositional geometries, internal bounding surfaces, and stratal relationships.

Old geophysical data applied to modern geological mapping problems: a case-study in the seridó belt, ne Brazil

The Serido belt, northeast Brazil, is a Brasiliano-Pan-African collisional orogen formed between the West African, Sao Francisco and Amazon cratons during the west Gondwana assemblage. This area is an excellent example for illustrating the usefulness of gamma-ray spectrometric data to support modern geological mapping in semi-arid terranes. Analyses of K, Th and U channels images, displayed as composite themes, correlate well with the main regional framework of the Serido Belt. Several distinct mapped units are easily distinguishable in the gamma-ray spectrometric data, as the Paleoproterozoic basement rocks and the supracrustal metasedimentary sequences of the Neoproterozoic Serido Group. Also, the granitic plutons and the Phanerozoic cover show different geophysical signatures. Definition of contacts among units, faults, folds and shapes of granitic intrusions are considerably enhanced by the airborne gammaray spectrometry data. The results here presented show that there is a strong relationship among geochemical, isotopic and geophysical signatures of different crustal blocks recognized in the region. This kind of approach seems fundamental for investigating regional crustal evolution in overly complex deformed Precambrian areas. It also can be of some help to better define the boundaries of the different lithostratigraphic units that could appear in similar orogenic belts within the Brazilian Shield.

OLD GEOPHYSICAL DATA APPLIED TO MODERN GEOLOGICAL MAPPING PROBLEMS: A CASE-STUDY IN THE SERIDÓ BELT, NE BRAZIL

The Seridó belt, northeast Brazil, is a Brasiliano-Pan-African collisional orogen formed between the West African, São Francisco and Amazon cratons during the west Gondwana assemblage. This area is an excellent example for illustrating the usefulness of gamma-ray spectrometric data to support modern geological mapping in semi-arid terranes. Analyses of K, Th and U channels images, displayed as composite themes, correlate well with the main regional framework of the Seridó Belt. Several distinct mapped units are easily distinguishable in the gamma-ray spectrometric data, as the Paleoproterozoic basement rocks and the supracrustal metasedimentary sequences of the Neoproterozoic Seridó Group. Also, the granitic plutons and the Phanerozoic cover show different geophysical signatures. Definition of contacts among units, faults, folds and shapes of granitic intrusions are considerably enhanced by the airborne gammaray spectrometry data. The results here presented show that there is a strong relationship among geochemical, isotopic and geophysical signatures of different crustal blocks recognized in the region. This kind of approach seems fundamental for investigating regional crustal evolution in overly complex deformed Precambrian areas. It also can be of some help to better define the boundaries of the different lithostratigraphic units that could appear in similar orogenic belts within the Brazilian Shield.

The utility of conductivity surveying and resistivity sounding in evaluating sand and gravel deposits and mapping drift sequences in northeast Scotland

Two types of ground geophysical survey, using portable equipment capable of one-man operation, have been used with the aim of elucidating the thickness and extent of sources of potentially workable sand and gravel in northeast Scotland. Vertical resistivity soundings have provided point data that allow extrapolation of the drift succession between exposures, boreholes and trial pits. Lateral profiling of ground conductivity using a non-contacting electromagnetic conductivity meter has proved to be of little use as an aid to conventional geological mapping in determining the position and extent of surface spreads of sand and gravel. Resistivity sounding, using Offset Wenner apparatus in particular, represents a rapid, low-cost method applicable by industry to the preliminary investigation of the thickness of sand and gravel at proposed extraction sites, especially in areas where modern geological maps are not available, or where ground disturbance has to be minimised.

Mineralogical Maps as Forerunners of Modern Geological Maps

Mineralogical Maps as Forerunners of Modern Geological Maps

Mineralogical Maps as Forerunners of Modern Geological Maps

Abstract This paper traces the development of geological cartography from the eighteenth century practice of marking the location of mineral deposits on topographic maps through to the development of the present day geological map showing the distribution of geological formations. By the opening of the nineteenth century the geological map had largely superseded the mineralogical map, although certain characteristics of the latter persisted for much longer.

Obituary Notices

WE regret to announce the death on August 3 of Prof. Josef Woldrich, director of the State Geological Institute at Prague, at the age of fifty-seven years. Born in Vienna, Prof. Woldrnich became well known in Central Europe for his geological investigations, which began with a re-examination of certain Bohemian rocks, notably those studied by the Frenchman Barrande and more recently by the late Prof. J. E. Marr of Cambridge. After the Great War, he was appointed to the chair of geology at the new University of Brno in Moravia. Here he commenced a series of geological studies of the lesser-known districts of Slovakia, a work of extreme importance for the compilation of the modern geological maps of Czechoslovakia. He had been director of the State Geological Institute for the past three years.