Glacier retreat during the recent eruptive period of Popocaté petl volcano, Mexico

AbstractPopocatépetl (19°02’ N, 98°62’W; 5424 m) is one of the largest active stratovolcanoes in the Transmexican Volcanic Belt. A glacier located on the north side has undergone severe ablation since the volcano reinitiated eruptive activity in December 1994. In our study, we calculate the extent of the glacier recession and the loss in glacial mass balance during the period of greatest laharic activity (1994–2002), using photogrammetric treatment of 20 pairs of aerial photographs. The results indicate that from November 1997 to December 2002, the glacier released approximately 3 967 000 m3 of water. A period of intense glacier melting occurred from 4 November 2000 to 15 March 2001 during which time 717 000 m3 of water was released. Much of the melting was attributed to the pyroclastic flow that took place on 22 January 2001 and produced a 14.2 km lahar with 68 000 m3 of water. Among the many types of volcanic events, pyroclastic flows were the most effective in causing sudden snowmelt, although small explosions were also effective since they deposited incandescent material on the glacier. The collapse of the plinian columns covered the glacier with pyroclasts and increased its volume. The existence of control points for georeferencing and a knowledge of the topography underlying the glacier previous to the eruption would have provided more accurate and useful results for hazard prevention.

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The Temple of Sulis-Minerva at Bath

The Journal of Roman Studies ◽

10.2307/298749 ◽

1955 ◽

Vol 45 (1-2) ◽

pp. 97-105 ◽

Cited By ~ 1

Author(s):

I. A. Richmond ◽

J. M. C. Toynbee

Keyword(s):

Eighteenth Century ◽

Hot Springs ◽

South Side ◽

British Art ◽

The North ◽

North Side ◽

Central Member ◽

The Many ◽

The Temple

The Roman remains at Bath, dominated by the stately thermal establishment, have always been associated in geography and in archaeology with the goddess Sulis-Minerva. The famous pediment of her temple, found when the eighteenth-century Pump Room was built, has long been accounted one of the most remarkable manifestations of Romano-British art; its richly carved reliefs have always invited restoration; and they at once received it, somewhat sketchily from Englefield and most ingeniously from Samuel Lysons in 1802 (pl. XXIII). So convincing, indeed, was the main outline of Lyson's reconstruction that it held the field and remained the basis of all subsequent proposals, including that so carefully elaborated by the late A. J. Taylor. The discovery of the stones carried with it the site of the temple; for the blocks cannot have fallen far. It lay below the Pump Room, on the north side of the sacred pool whose copious hot springs were enclosed by the Romans in an irregular polygonal basin. The sanctity of the spring, which seems only later to have been roofed, is proved by the many coins and the leaden tablet inscribed with a curse which it contained, but, unlike many sacred pools, for example, that of Nemausus at Nîmes, it was not itself frequented by bathers. It could be viewed from the Baths through three great open windows on its south side; and these were of some architectural pretensions, the central member having a true arch, and the flanking pair (of which one survives (pl. XXIV, 2)) joggled flat arches, while the corridor within was furnished, as was no other part of the Baths, with fluted pilasters (pl. XXIV, 1).

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Excavations and Discoveries in the Forum Romanum and on the Palatine during the last Fifty Years

The Journal of Roman Studies ◽

10.2307/298300 ◽

1960 ◽

Vol 50 (1-2) ◽

pp. 192-203 ◽

Cited By ~ 1

Author(s):

Gianfilippo Carettoni

Keyword(s):

Twentieth Century ◽

Aerial Photographs ◽

Clear Picture ◽

The South ◽

Early Christian ◽

The North ◽

Imperial Palace ◽

North Side ◽

Intensive Work

The first decade of the twentieth century ended with a substantial sum of important discoveries in the Forum to its credit. Between 1898 and 1903 Giacomo Boni's intensive work had resulted in sensational finds—the Lapis Niger, the republican Comitium and the archaic cemetery ; he had finished excavating both on the north side of the Forum, uncovering the front of the Basilica Aemilia and the Curia, and to the south, where the shrine of the Fountain of Juturna had returned to light, together with the approach from the Forum to the Imperial Palace and the series of early Christian paintings in S. Maria Antiqua. Excavation of the House of the Vestals was also brought to completion. Interest in republican and archaic development had led to investigation beneath the paving of the Forum itself (Equus Domitiani, Lacus Curtius, underground galleries and ritual wells and pits), and to a search for the ancient track of the Via Sacra, with exploration of its shops and wells of Republican date. A mass of information and material collected as a result of these excavations has unfortunately, although scrupulously catalogued, remained largely unpublished. Aerial photographs made at this time give a clear picture of the Forum valley during the first years of the century : one vast excavation stretching from the Vulcanal to the Arch of Titus.

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Morphogenesis and quantification of the pore space in a tephra-palaeosol sequence in Tlaxcala, central Mexico

Soil Research ◽

10.1071/sr18185 ◽

2019 ◽

Vol 57 (6) ◽

pp. 559 ◽

Cited By ~ 1

Author(s):

L. Pogosyan ◽

A. Gastelum ◽

B. Prado ◽

J. Marquez ◽

K. Abrosimov ◽

...

Keyword(s):

Pore Space ◽

Volcanic Belt ◽

Pyroclastic Flows ◽

Homogeneous Distribution ◽

Central Mexico ◽

Consolidation Process ◽

Cross Sectional ◽

Undisturbed Soil ◽

Thin Sections ◽

The North

Tepetates are indurated subsoil horizons developed in tephra-derived materials in various parts of the Trans-Mexican Volcanic Belt. The term ‘tepetate’ includes fragipans, duripans, pedosediments and saprolites, derived from vitric rhyolitic tuff, Pleistocene volcanic ashes or pyroclastic flows. All soils with tepetates are at high risk of erosion and so they have been intensively studied for decades. The tepetates are common in Tlaxcala State of central Mexico, being formed under Ustic Isomesic soil climate. The aim of this investigation was to characterise the pore space of fragipan-type tepetates and the role of clay components in their formation. We studied porosity of tepetate from a tephra-palaeosol sequence in the north of Tlaxcala State, in undisturbed soil samples. Observations of pore space were made in 2D and 3D by analysing microscope images of thin sections and cross-sectional images from a computed tomography scanner. In the thin sections we also identified and described clay illuvial pedofeatures. Micromorphological observations showed two main pore types. Small rounded pores had a homogeneous distribution and were probably formed before the clay illuviation process that took place in a palaeosol formed on the tepetate material. The distribution pattern of the small pores in the studied tepetate was similar to that in the fragic horizon, which was probably formed by a hydro-consolidation process. Large crack-pores were formed during the palaeosol formation. Later these large pores were filled by illuvial clay coatings and so we conclude that each tepetate was part of the set of Bt horizons in the palaeosols of Luvisol type.

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Art. II.—Aśwakrāntā, near Ganhati

Journal of the Royal Asiatic Society of Great Britain & Ireland ◽

10.1017/s0035869x0002726x ◽

1900 ◽

Vol 32 (1) ◽

pp. 25-27

Author(s):

P. R. Gurdon

Keyword(s):

Reverse Current ◽

The West ◽

The North ◽

North Side ◽

The People ◽

The Many ◽

The Temple

Amongst the many interesting places that lie near the old town of Pragjotishpur or Ganhati is Aśwakrāntā, or, as some people call it, Aśwakrāntā. It is called Aśwakrāntā because the route of Krishna is said to have been viâ Aśwakrāntā when he was carrying off his bride, Rukmini (Aśwa ‘horse’ and krāntā ‘passed by’). If it is called Aśwakrāntā, it means the place where the horse was tired; klāntā meaning ‘tired’ or ‘ weary.’ It should also be remembered that r and l are often interchangeable. Compare Sukreshwar, which is often called Sukleshwar. Aśwakrāntā, or Aśwakrāntā, is on the north side of the Brahmaputra, a little to the west of the island of Umananda, which lies in the midst of the mighty Brahmaputra. The people at the temple show you various holes in the rock at Aśwakrāntā, which, they say, are the footprints of Krishṇna's horses. It is at this place that the people bathe during the Asokastami festival, the day when the current of the Brahmaputra is thought to flow backwards, the reverse current being popularly supposed to be the holy Gangā. The origin of the festival is said to be due to Aśwakrāntā having been the bathing-place of Rukminī. This goddess bathed in the river, but was annoyed by people staring at her from the opposite bank, upon which Krishṇa promptly interposed what is now known as the “ Ar parbat” as a screen.

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A Radiocarbon-dated Collared Urn from Oban

Scottish Archaeological Journal ◽

10.3366/saj.2001.23.2.105 ◽

2001 ◽

Vol 23 (2) ◽

pp. 105-118

Author(s):

CHRISTOPHER LOWE ◽

ANN MacSWEEN ◽

KATHLEEN McSWEENEY

Keyword(s):

The North ◽

North Side ◽

Funerary Ritual

A collared urn was found during the course of a watching-brief on the raised beach on the north side of Oban bay. Post-excavation analysis has succeeded in throwing some further light on the chronology of this type of urn and possibly on some elements of the funerary ritual associated with its burial. The same watching-brief also revealed the site of a truncated pit of medieval date, filled with fire-cracked stones.

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