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At least 37 records · Page 2Linked to original sources
USGS1967

(LAC-38) Geologic map of the Seleucus quadrangle of the moon

The Seleucus quadrangle lies in the northwestern part of the Oceanus Procellarum , a large mare of irregular shape in the western part of the earthside hemisphere of the Moon. Material of the mare occupies most of the quadrangle. Craters ranging from 1 to 44 km in diameter are scattered over the smooth mare surface; in addition, a few isolated hills and ridges rise above the mare. In the east-central part of the quadrangle, the Aristarchus plateau (informal name ) slopes gently westward and merges with the surrounding surface of Oceanus Procellarum . The plat eau is also known for its reddish color and light absorption properties (Wood, 1912), and areas where occasional reddish glows have been seen (Greenacre, 1965).

IMAP↗
USGS1973

Geologic map of the Grimaldi quadrangle of the Moon

The Grimaldi quadrangle lies at the southwest margin of Oceanus Procellarum about 1,000 km east of Orientale, the youngest o f the lunar multi-ringed basins. The distal ends of the ejecta blanket surrounding the Orient al e basin partly covers the western third of the quadrangle. The relatively small, two-ring Grimaldi basin is in the northwest corner of the quadrangle, and the Humorum basin l ies about 750 km to the southeast. A vestigial multi-ring basin mostly engulfed by mare appears to control the distribution of terra and mare along the southwest margin of Oceanus Procellarum ; the craters Hansteen and Billy are on a northwe s t-trending topographic high which represents part of the ring system of this basin. Terra materials of distinctive texture, apparently unrelated to multi-ring basins and probably of volcanic origin, occupy the central parts of the quadrangle.

IMAP↗
USGS1973

Geologic map of the Rumker Quadrangle of the Moon

The Rumker quadrangle, in the northwest quadrant of the Moon, is adjacent to the western rim of the multi-ring Imbrium basin and to Sinus Iridum , a large (220 km diameter) mare-filled crater. Both of these great depressions were probably formed by impa c t, as indicated here and elsewhere on the Moon by the characteri stic form, distribution, and texture of surrounding materials and structures. The Imbrium b asin and Iridum crater were filled by mare mat erials during the Imbrain and Eratosthenian Periods. In this quadrangle, the widespread ejecta blanke t of the Imbrium basin, as well as the basin’s concentric ridges and mountain rings, has largely been buried by terra materials of mixed origin and by ejecta from Iridum and numerous smaller impact craters. These materials , together with some terra units of probable volcanic origin, make up the highland terrain. Mare materials of Oceanus Procellarum cover part of t his westward-sloping highland shelf that separate it from the Rumker Hills, an isolated plateau surrounded by the mare. No visible discontinuity distinguishes mare material of Oceanus Procella rum from those in the Imbrium basin, both of which contain several units having similar albedo and color. Parts of the mare are very dark and smooth and appear relatively young, and parts of the terra contain many diverse landforms of Imbrian and younger age that appear to be volcanic . This region may therefore have been more active internally during late stages of lunar history than many others on the near side.

IMAP↗
USGS1981

Single-channel seismic-reflection profiles and sidescan-sonar records collected on Georges Bank

Subbottom seismic-reflection, echo-sounding, and sidescan-sonar records were collected by the U.S. Geological Survey during two cruises over Georges Bank aboard the R/V OCEANUS (cruise 056, March 6-15, 1979 and cruise 067, August 6-13, 1979) (fig. 1). The data collected during these two cruises contributed to a study of bed-form types and distribution and of sediment transport paths on Georges Bank. The equipment used on these cruises consisted of an EG&G Uniboom 12-kHz echo-sounder, and Klein sidescan-sonar system. The Uniboom data were collected on the OCEANUS 067 cruise along 185 km of trackline (fig. 1), and the 12-kHz echo-sounder and sidescan-sonar data were collected during both cruises along 465 km of trackline. Navigation during both cruises consisted of Loran-C fixes logged at least every 15 minutes. After the cruise, the navigation data were digitized and stored on magnetic tape. The original records can be studied at the U.S. Geological Survey Data Library at Woods Hole, MA 02543. Microfilm copies of the subbottom, echo-sounding, and sidescan-sonar records can be purchased only from the National Geophysical and Solar-Terrestrial Data Center, NOAA/EDIS/NGSDC, Code D621, 325 Broadway, Boulder, CO 80303 (303-497-6338).

Georges Bank↗
USGS1979

Lunar magnetic anomalies detected by the Apollo substatellite magnetometers

Properties of lunar crustal magnetization thus far deduced from Apollo subsatellite magnetometer data are reviewed using two of the most accurate presently available magnetic anomaly maps - one covering a portion of the lunar near side and the other a part of the far side. The largest single anomaly found within the region of coverage on the near-side map correlates exactly with a conspicuous, light-colored marking in western Oceanus Procellarum called Reiner Gamma. This feature is interpreted as an unusual deposit of ejecta from secondary craters of the large nearby primary impact crater Cavalerius. An age for Cavalerius (and, by implication, for Reiner Gamma) of 3.2 ?? 0.2 ?? 109 y is estimated. The main (30 ?? 60 km) Reiner Gamma deposit is nearly uniformly magnetized in a single direction, with a minimum mean magnetization intensity of ???7 ?? 10-2 G cm3/g (assuming a density of 3 g/cm3), or about 700 times the stable magnetization component of the most magnetic returned samples. Additional medium-amplitude anomalies exist over the Fra Mauro Formation (Imbrium basin ejecta emplaced ???3.9 ?? 109 y ago) where it has not been flooded by mare basalt flows, but are nearly absent over the maria and over the craters Copernicus, Kepler, and Reiner and their encircling ejecta mantles. The mean altitude of the far-side anomaly gap is much higher than that of the near-side map and the surface geology is more complex, so individual anomaly sources have not yet been identified. However, it is clear that a concentration of especially strong sources exists in the vicinity of the craters Van de Graaff and Aitken. Numerical modeling of the associated fields reveals that the source locations do not correspond with the larger primary impact craters of the region and, by analogy with Reiner Gamma, may be less conspicuous secondary crater ejecta deposits. The reason for a special concentration of strong sources in the Van de Graaff-Aitken region is unknown, but may be indirectly related to the existence of strongly modified crustal terrain which also occurs in the same region. The inferred directions of magnetization for the several sources of the largest anomalies are highly inclined with respect to one another, but are generally depleted in the north-south direction. The north-south depletion of magnetization intensity appears to continue across the far-side within the region of coverage. The mechanism of magnetization and the origin of the magnetizing field remain unresolved, but the uniformity with which the Reiner Gamma deposit is apparently magnetized, and the north-south depletion of magnetization intensity across a substantial portion of the far side, seem to require the existence of an ambient field, perhaps of global or larger extent. The very different inferred directions of magnetization possessed by nearly adjacent sources of the Van de Graaff-Aitken anomalies, and the depletion in their north-south component of magnetization, do not favor an internally generated dipolar field oriented parallel to the present spin axis. A variably oriented interplanetary magnetizing field that was intrinsically strong or locally amplified by unknown surface processes is least inconsistent with the data. ?? 1979.

Physics of the Earth and Planetary Interiors↗
USGS2011

The Mairan domes: silicic volcanic constructs on the Moon

The Mairan domes are four features located in northern Oceanus Procellarum at ∼312.3E, 41.4N on the Moon. High resolution visible imagery, visible-to-mid-IR spectra, and Lunar Prospector Th abundance data all indicate that these four domes have a composition that is consistent with derivation from a Si-rich, highly evolved magma.

Geophysical Research Letters↗
USGS1979

The Moon: Sources of the crustal magnetic anomalies

Previously unmapped Apollo 16 subsatellite magnetometer data collected at low altitudes over the lunar near side are presented. Medium-amplitude magnetic anomalies exist over the Fra Mauro and Cayley Formations (primary and secondary basin ejecta emplaced 3.8 to 4.0 billion years ago) but are nearly absent over the maria and over the craters Copernicus, Kepler, and Reiner and their encircling ejecta mantles. The largest observed anomaly (radial component ∼21 gammas at an altitude of 20 kilometers) is exactly correlated with a conspicuous light-colored deposit on western Oceanus Procellarum known as Reiner γ. Assuming that the Reiner γ deposit is the source body and estimating its maximum average thickness as 10 meters, a minimum mean magnetization level of 5.2 ± 2.4 × 10 –2 electromagnetic units per gram, or ∼500 times the stable magnetization component of the most magnetic returned sample, is calculated. An age for its emplacement of ≲ 2.9 billion years is inferred from photogeologic evidence, implying that magnetization of lunar crustal materials must have continued for a period exceeding 1 billion years.

Science↗
USGS1994

Clementine observations of the Aristarchus region of the moon

Multispectral and topographic data acquired by the Clementine spacecraft provide information on the composition and geologic history of the Aristarchus region of the moon. Altimetry profiles show the Aristarchus plateau dipping about 1° to the north-northwest and rising about 2 kilometers above the surrounding lavas of Oceanus Procellarum to the south. Dark, reddish pyroclastic glass covers the plateau to average depths of 10 to 30 meters, as determined from the estimated excavation depths of 100- to 1000-meter-diameter craters that have exposed materials below the pyroclastics. These craters and the walls of sinuous rilles also show that mare basalts underlie the pyroclastics across much of the plateau. Near-infrared images of Aristarchus crater reveal olivine-rich materials and two kilometer-sized outcrops of anorthosite in the central peaks. The anorthosite could be either a derivative of local magnesium-suite magmatism or a remnant of the ferroan anorthosite crust that formed over the primordial magma ocean.

Science↗
USGS1977

Geologic map of the west side of the Moon

The west limb region of the M oon consists of highly cratered terra rising 5 km or more above the mare of Oceanus Procellarum and most of the lunar near side. Crustal material in this area of large basins and craters has been redistributed repeatedly by giant impacts. The early historical record of these events is apparently preserved in a complex of interlayered breccias, which may be partly exposed in the walls of the larger craters. Orientale, the last multiringed basin, was formed early in lunar history during the wanning stages of high impact flux by a large body probably impacting the surface obliquely from the northeast. Ejecta from this impact was widely scattered by over the Moon and appears to form some of the plains materials. Although the major landforms of the Oriental basin were developed instantaneously in geologic terms, isostatic adjustments were more protracted; the accompanying structural dislocations including concentric and radial faults in the floor material may have continued u p to the time of mare basalt flooding after basin formation. Subsequent impacts have produced craters generally less than 60 km diameter.

IMAP↗
USGS1973

Geologic map of the Byrgius Quadrangle of the Moon

The By rgius quadrangle, at the western edge of the near side, lies in the terra southwest of Oceanus Procellarum between the Humorum and Orientale basins. Structures and deposits related to the Orientale basin, which is younger than the Humorum basin (Hartmann and Kuiper, 1962 ), dominate the southwestern half of the quadrangle . The northeastern half is dominated by mantling deposits that are older than Orientale ( Imbrian ) and younger than Humorum (pre- Imbrian ), which lies mostly outside the zone of reco gnizable Orientale-related deposits or structures. These main subdivisions are visible on the albedo map of the Moon ( Pohn and Wildey , 1970) , the northeastern one having generally the lower albedo . The older units throughout the quadrangle have complex topography, probably formed mostly intersecti ng, degraded craters .

IMAP↗
USGS2006

High-resolution chirp seismic reflection data acquired from the Cap de Creus shelf and canyon area, Gulf of Lions, Spain in 2004

Seismic reflection data were collected from the Cap de Creus shelf and canyon in the southwest portion of the Gulf of Lions in October 2004. The data were acquired using the U.S. Geological Survey`s (USGS) high-resolution Edgetech CHIRP 512i seismic reflection system aboard the R/V Oceanus. Data from the shipboard 3.5 kHz echosounder were also collected but are not presented here. The seismic reflection data were collected as part of EuroSTRATAFORM funded by the Office of Naval Research. In October 2004, more than 200 km of high resolution seismic reflection data were collected in water depths ranging 30 m - 600 m. All data were recorded with a Delph Seismic PC-based digital recording system and processed with Delph Seismic software. Processed sections were georeferenced into tiff images for digital archive, processing and display. Penetration ranged 20-80 m. The data feature high quality vertical cross-section imagery of numerous sequences of Quaternary seismic stratigraphy. The report includes trackline maps showing the location of the data, as well as both digital data files (SEG-Y) and images of all of the profiles. The data are of high quality and provide new information on the location and thickness of sediment deposits overlying a major erosion surface on the Cap de Creus shelf; they also provide new insight into sediment processes on the walls and in the channel of Cap de Creus Canyon. These data are under study by researchers at the US Geological Survey, the University of Barcelona, and Texas A and M University. Copies of the data are available to all researchers.

Open-File Report↗
USGS1967

Preliminary geologic map of Ellipse III-9-5 and vicinity

Ellipse III-9-5 is in a level area between Mare Cognitum and Oceanus Procellarum, approximately 125 km southeast of the crater Lansberg. Mare material within the map area is covered with a greater number of subdued craters than typical smooth mare.

Open-File Report↗
USGS1967

Preliminary geologic map of Lunar Orbiter site of orb II P-13

Site II P-13 is in Oceanus Procellarum, about midway between craters Kepler to the northeast and Flamsteed to the southwest. Terra materials occur only in the northeast corner of the site. The rest of the area is covered by mare. On full-moon photographs the site appears to be largely an area of dark mare crossed by faint rays radial to Kepler.

Open-File Report↗