Constructing abstract maps from spatial descriptions for goal-directed exploration

This paper describes ongoing work on a system using spatial descriptions to construct abstract maps that can be used for goal-directed exploration in an unfamiliar office environment. Abstract maps contain membership, connectivity, and spatial layout information extracted from symbolic spatial information. In goal-directed exploration, the robot would then link this information with observed symbolic information and its grounded world representation. We demonstrate the ability of the system to extract and represent membership, connectivity, and spatial layout information from spatial descriptions of an office environment. In the planned study, the robot will navigate to the goal location using the abstract map to inform the best direction to explore in.

Geology alive. GeoBizirik.org

Geology is the science that studies the Earth, its composition, structure and origin in addition to past and present phenomena that leave their mark on rocks. So why does society need geologists? Some of the main reasons are listed below: - Geologists compile and interpret information about the earth’s surface and subsoil, which allows us to establish the planet’s past history, any foreseeable changes and its relationship with the rest of the solar system. - Society needs natural resources (metals, non-metals, water and fossil fuels) to survive. The work of geologists is therefore a key part of finding new deposits and establishing a guide for exploring and managing resources in an environmentally-friendly way. - The creation of geological maps allows us to identify potential risk areas and survey different land uses; in other words, they make an essential contribution to land planning and proposing sustainable development strategies in a region. - Learning about Geology and the proper use of geological information contributes to saving lives and reducing financial loss caused by natural catastrophes such as earthquakes, tsunamis, volcanic eruptions, flooding and landslides, while also helping to develop construction projects, public works, etc. Through the proposed activities we aim to explain some of the basic elements of the different specialities within the field of Geological Sciences. In order to do this, four sessions have been organised that will allow for a quick insight into the fields of Palaeontology, Mineralogy, Petrology and Tectonics.

Geology alive. GeoBizirik.org

Geology is the science that studies the Earth, its composition, structure and origin in addition to past and present phenomena that leave their mark on rocks. So why does society need geologists? Some of the main reasons are listed below: - Geologists compile and interpret information about the earth’s surface and subsoil, which allows us to establish the planet’s past history, any foreseeable changes and its relationship with the rest of the solar system. - Society needs natural resources (metals, non-metals, water and fossil fuels) to survive. The work of geologists is therefore a key part of finding new deposits and establishing a guide for exploring and managing resources in an environmentally-friendly way. - The creation of geological maps allows us to identify potential risk areas and survey different land uses; in other words, they make an essential contribution to land planning and proposing sustainable development strategies in a region. - Learning about Geology and the proper use of geological information contributes to saving lives and reducing financial loss caused by natural catastrophes such as earthquakes, tsunamis, volcanic eruptions, flooding and landslides, while also helping to develop construction projects, public works, etc. Through the proposed activities we aim to explain some of the basic elements of the different specialities within the field of Geological Sciences. In order to do this, four sessions have been organised that will allow for a quick insight into the fields of Palaeontology, Mineralogy, Petrology and Tectonics.

the ebb-tidal delta of the venice lagoon,Italy

Very high-resolution seismic lines were collected offshore the Venice Lagoon in the framework of the Co.Ri.La'New very high resolution seismic methods to study the Venice Lagoon subsoil' project. The 140 km boomer profiles led to the identification of a convex-upward,lens-shaped body just outside the Lido inlet,one of the three lagoon inlets,which has been interpreted as an ebb-tidal delta.The comparison between the scismostratigraphic setting og this deposit, as revealed by the seismic lines,and the analyses of historicalbathymetric maps highlighted the key role of human interventions in the formation and evolution of the Lido inlet cbb-tidal delta.To preserve the lagoon environment but also to ensure a navigable way, human interventions at the Lidoinlet,performed since the fourteenth centtury, caused profound variations in the inlet dynamics,ldading to a progressive increase in the sediment dispersion from the lagoon interior towards the sea. The ebb-tidal delta of the Lido nilet is thus a very recent feature compared with the formation of the Venice lagoon and formed mainly as a consequence of the construction of the two jetties that have bound the inlet form AD 1886 to the present day.

The vegetation and climate history of the last glacial cycle in a new pollen record from Lake Fimon (southern Alpine foreland, N-Italy)

The sediments of Like Fimon N Italy contain the first continuous archive of the Late Pleistocene environmental and climate history of the southern Alpine foreland We present here the detailed palynological record of the interval between Termination II and the List Glacial Maximum The age-depth model is obtained by radiocarbon dating in the uppermost part of the record Downward we con elated major forest expansion and contraction events to isotopic events in the Greenland Ice core records via a stepping-stone approach involving intermediate correlation to isotopic events dated by TIMS U/Th in Alpine and Apennine stalagmites and to pollen records from mime cores of the Iberian margin Modelled ages obtained by Bayesian analysis of deposition are thoroughly consistent with actual ages with maximum offset of +/- 1700 years Sharp expansion of broad-leaved temperate forest and of sudden water table rise mark the onset of the Last Interglacial after a treeless steppe phase at the end of penultimate glaciation This event is actually a two-step process which matches the two step rise observed in the isotopic record of the nearby Antro del Corchia stalagmite respectively dated to 132 5 +/- 2 5 and 129 +/- 1 5 ka At the interglacial decline mixed oak forests were replaced by oceanic mixed forests the latter persisting further for 7 ka till the end of the Eemian succession Warm-temperate woody species are still abundant at the Eemian end corroborating a steep gradient between central Europe and the Alpine divide at the inception of the last glacial After a stadial phase marked by moderate forest decline a new expansion of warm broad leaved forests interrupted by minor events and followed by mixed oceanic forests can be identified with the north-alpine Saint Germain I The spread of beech during the oceanic phase is a valuable circumalpine marker The subsequent stadial-interstadial succession lacking the telocratic oceanic phase is also consistent with the evidence at the north alpine foreland The Middle Wurmian (full glacial) is marked by persistence of mixed forests dominated by conifers but with significant lime and other broad leaved species A major Arboreal Pollen decrease is observed at modelled age of 38 7 +/- 0 5 ka (larch expansion and last occurrence of lime) which his been related to Heinrich Event 4 The evidence of afforestation persisting south of the Alps throughout most of MIS 3 contrasts with a boreal and continental landscape known for the northern alpine foreland pointing to a sharp rainfall boundary at the Alpine divide and to southern air circulation This is in agreement with the Alpine paleoglaciological record and is supported by the pressure and rainfall patterns designed by mesoscale paleoclimate simulations Strenghtening the continental high pressure during the full glacial triggered cyclogenesis in the middle latitude eastern Europe and orographic rainfall in the eastern Alps and the Balkanic mountains thus allowing forests development at current sea level altitudes (C) 2010 Elsevier Ltd All rights reserved

Compositional data-driven alternatives to single geochemical component maps

Conventional practice in Regional Geochemistry includes as a final step of any geochemical campaign the generation of a series of maps, to show the spatial distribution of each of the components considered. Such maps, though necessary, do not comply with the compositional, relative nature of the data, which unfortunately make any conclusion based on them sensitive
to spurious correlation problems. This is one of the reasons why these maps are never interpreted isolated. This contribution aims at gathering a series of statistical methods to produce individual maps of multiplicative combinations of components (logcontrasts), much in the flavor of equilibrium constants, which are designed on purpose to capture certain aspects of the data.
We distinguish between supervised and unsupervised methods, where the first require an external, non-compositional variable (besides the compositional geochemical information) available in an analogous training set. This external variable can be a quantity (soil density, collocated magnetics, collocated ratio of Th/U spectral gamma counts, proportion of clay particle fraction, etc) or a category (rock type, land use type, etc). In the supervised methods, a regression-like model between the external variable and the geochemical composition is derived in the training set, and then this model is mapped on the whole region. This case is illustrated with the Tellus dataset, covering Northern Ireland at a density of 1 soil sample per 2 square km, where we map the presence of blanket peat and the underlying geology. The unsupervised methods considered include principal components and principal balances
(Pawlowsky-Glahn et al., CoDaWork2013), i.e. logcontrasts of the data that are devised to capture very large variability or else be quasi-constant. Using the Tellus dataset again, it is found that geological features are highlighted by the quasi-constant ratios Hf/Nb and their ratio against SiO2; Rb/K2O and Zr/Na2O and the balance between these two groups of two variables; the balance of Al2O3 and TiO2 vs. MgO; or the balance of Cr, Ni and Co vs. V and Fe2O3. The largest variability appears to be related to the presence/absence of peat.

Weighted Logratio Biplots, Correspondence Analysis and Spectral Maps

Starting with logratio biplots for compositional data, which are based on the principle of subcompositional coherence, and then adding weights, as in correspondence analysis, we rediscover Lewi's spectral map and many connections to analyses of two-way tables of non-negative data. Thanks to the weighting, the method also achieves the property of distributional equivalence

Analysis of Pleistocene paleodrainage evolution in the Po Basin (Italy) by multivariate statistical techniques

In order to obtain a high-resolution Pleistocene stratigraphy, eleven continuously cored boreholes, 100 to 220m deep were drilled in the northern part of the Po Plain by Regione Lombardia in the last five years. Quantitative provenance analysis (QPA, Weltje and von Eynatten, 2004) of Pleistocene sands was carried out by using multivariate statistical analysis (principal component analysis, PCA, and similarity analysis) on an integrated data set, including high-resolution bulk petrography and heavy-mineral analyses on Pleistocene sands and of 250 major and minor modern rivers draining the southern flank of the Alps from West to East (Garzanti et al, 2004; 2006). Prior to the onset of major Alpine glaciations, metamorphic and quartzofeldspathic detritus from the Western and Central Alps was carried from the axial belt to the Po basin longitudinally parallel to the SouthAlpine belt by a trunk river (Vezzoli and Garzanti, 2008). This scenario rapidly changed during the marine isotope stage 22 (0.87 Ma), with the onset of the first major Pleistocene glaciation in the Alps (Muttoni et al, 2003). PCA and similarity analysis from core samples show that the longitudinal trunk river at this time was shifted southward by the rapid southward and westward progradation of transverse alluvial river systems fed from the Central and Southern Alps. Sediments were transported southward by braided river systems as well as glacial sediments transported by Alpine valley glaciers invaded the alluvial plain. Kew words: Detrital modes; Modern sands; Provenance; Principal Components Analysis; Similarity, Canberra Distance; palaeodrainage

Using self organizing maps on compositional data

Self-organizing maps (Kohonen 1997) is a type of artificial neural network developed to explore patterns in high-dimensional multivariate data. The conventional version of the algorithm involves the use of Euclidean metric in the process of adaptation of the model vectors, thus rendering in theory a whole methodology incompatible with non-Euclidean geometries. In this contribution we explore the two main aspects of the problem: 1. Whether the conventional approach using Euclidean metric can shed valid results with compositional data. 2. If a modification of the conventional approach replacing vectorial sum and scalar multiplication by the canonical operators in the simplex (i.e. perturbation and powering) can converge to an adequate solution. Preliminary tests showed that both methodologies can be used on compositional data. However, the modified version of the algorithm performs poorer than the conventional version, in particular, when the data is pathological. Moreover, the conventional ap- proach converges faster to a solution, when data is \well-behaved". Key words: Self Organizing Map; Artificial Neural networks; Compositional data

PhotoLin: a program to identify and analyze linear structures in aerial photographs, satellite images and maps

A computer program, PhotoLin, written for an IBM-PC-compatible microcomputer is described which detects linear features in aerial photographs, satellite images and topographic maps. The program accepts images saved to PCX files as input and applies noise correction and smoothing filters and thinning routines. The output consists of a skeleton containing the median lines of linear features which can be represented on a map. The branches of the skeleton can be broken into sections of constant length for which the mean orientations are obtained for the preparation of rose diagrams. (C) 2001 Elsevier B.V. Ltd. All rights reserved.

Finite-strain analysis in orthogneiss of the Gran Paradiso massif, Western Alps, Italy

A finite-strain study in the Gran Paradiso massif of the Italian Western Alps has been carried out to elucidate whether ductile strain shows a relationship to nappe contacts and to shed light on the nature of the subhorizontal foliation typical of the gneiss nappes in the Alps. The Rf/_ and Fry methods used on feldspar porphyroclasts from 143 augengneiss and 11 conglomerate samples of the Gran Paradiso unit (upper tectonic unit of the Gran Paradiso massif), as well as, 9 augengneiss (Erfaulet granite) and 3 quartzite conglomerate samples from the underlying Erfaulet unit (lower unit of the Gran Paradiso massif), and 1 sample from mica schist. Microstructures and thermobarometric data show that feldspar ductility at temperatures >~450°C occurred only during high-pressure metamorphism, when the rocks were underplated beneath the overriding Adriatic plate. Therefore, the finite-strain data can be related to high-pressure metamorphism in the Alpine subduction zone. The augen gneiss was heterogeneously deformed and axial ratios of the strain ellipse in XZ sections range from 2.1 to 69.8. The long axes of the finite-strain ellipsoids trend W/WNW and the short axes are subvertical associated with a subhorizontal foliation. The strain magnitudes do not increase towards the nappe contacts. Geochemical work shows that the accumulation of finite strain was not associated with any significant volume strain. Hence, the data indicate flattening strain type in the Gran Paradiso unit and constrictional strain type in the Erfaulet unit and prove deviations from simple shear. In addition, electron microprobe work was undertaken to determine if the analysed fabrics formed during high-P metamorphism. The chemistry of phengites in the studied samples suggests that deformation and final structural juxtaposition of the Gran Paradiso unit against the Erfaulet took place during high-pressure metamorphism. On the other hand, nappe stacking occurred early during subduction probably by brittle imbrication and that ductile strain was superimposed on and modified the nappe structure during high-pressure underplating in the Alpine subduction zone. The accumulation of ductile strain during underplating was not by simple shear and involved a component of vertical shortening, which caused the subhorizontal foliation in the Gran Paradiso massif. It is concluded that this foliation formed during thrusting of the nappes onto each other suggesting that nappe stacking was associated with vertical shortening. The primary evidence for this interpretation is an attenuated metamorphic section with high-pressure metamorphic rocks of the Gran Paradiso unit juxtaposed against the Erfaulet unit. Therefore, the exhumation during high-pressure metamorphism in the Alpine subduction zone involved a component of vertical shortening, which is responsible for the subhorizontal foliation within the nappes.