Early human occupation of Western Europe: Paleomagnetic dates for two paleolithic sites in Spain

The lacustrine deposits infilling the intramontane Guadix-Baza Basin, in the Betic Range of Southern Spain, have yielded abundant well-preserved lithic artifacts. In addition, the lake beds contain a wide range of micromammals including Mimomys savini and Allophaiomys burgondiae and large mammals such as Mammuthus and Hippopotamus together with the African saber-toothed felid Megantereon. The association of the lithic artifacts along with the fossil assemblages, themselves of prime significance in the Eurasian mammal biochronology, is providing new insight into the controversy of the human settlement in Southern Europe. Despite the importance of the artifacts and fossil assemblage, estimates of the geological age of the site are still in conflict. Some attempts at dating the sediments have included biochronology, uranium series, amino acid racemization, and stratigraphic correlation with other well-dated sections in the basin, but so far have failed to yield unambiguous ages. Here we present paleomagnetic age dating at the relevant localities and thus provide useful age constraints for this critical paleoanthropological and mammal site. Our data provide firm evidence for human occupation in Southern Europe in the Lower Pleistocene, around 1 mega-annum ago. The current view of when and how hominids first dispersed into Europe needs to be reevaluated.

Applying Positive Psychology in Early Childhood.

The purpose of this paper is to introduce a framework for applying positive psychology in elementary classrooms. The target age group is children in grades K-3 (ages 5 to 8) because this age group can benefit the most from an early introduction to strategies that promote positive development (Cowne & Hightower, 1989; White, 1996). The following sections will: (a) introduce constructs of positive psychology; (b) present developmental data on how these constructs can be applied to children ages 5 to 8 years; (c) present ideas for incorporating positive psychology practice into K-3 classrooms; (d) present strategies for incorporating positive psychology with multicultural considerations; and (e) present ideas on how to implement strategies based on positive psychology that are compatible with grade level standards and sociopolitical teaching expectations.

(Table T1) Strontium isotopic composition and ages of limestone samples from ODP Hole 180-1118A

Limestone from Unit VI (857.1-859.15 meters below seafloor) collected at Site 1118 contains a planktonic foraminiferal fauna indicating a latest Miocene to early Pliocene age. Globorotalia tumida is recorded in Sample 180-1118A-68R-4, 46-48 cm, indicating an early Pliocene (N18) age at this level (J. Resig, pers. comm., 2000). Based on their known range in the western Papuan Basin, the presence of (rare) Lepidocyclina and common Amphistegina in some samples suggests that abundant shallow-water bioclastic debris present in these limestones may be reworked from older, possibly middle or early late Miocene sediments. Four samples were selected for whole-rock strontium isotopic analysis to further investigate this possibility. A petrographic examination of samples analyzed was also conducted.

Radiocarbon ages from Novaya Zemlya, Russia

Recent observations on postglacial emergence and past glacier extent for one of the least accessible areas in the Arctic, northern Novaya Zemlya are here united. The postglacial marine limit formed 5 to 6 ka is registered on the east and west coasts of the north island at 10 ± 1 and 18 ± 2 m aht, respectively. This modest and late isostatic response along with deglacial ages of >9.2 ka on adjacent marine cores from the northern Barents Sea indicate either early (>13 ka) deglaciation or modest ice sheet loading (<1500 m thick ice sheet) of Novaya Zemlya. Older and higher (up to 50 m aht) raised beaches were identified beneath a discontinuous glacial drift. Shells from the drift and underlying sublittoral sediments yield minimum limiting 14C ages of 26 to 30 ka on an earlier deglacial event(s). The only moraines identified are within 4 km of present glacier margins and reflect at least three neoglacial advances in the past 2.4 ka.

Ages, biostratigraphic datums, and coiling ratios of Pulleniatina in sediments from DSDP Holes 15-154A and 16-157

Pliocene and Pleistocene planktonic foraminiferal biogeography and paleoceanography have been examined in Deep Sea Drilling Project (DSDP) sites of the Panama Basin (Pacific Ocean) and Colombian and Venezuelan Basins (Atlantic Ocean) to determine the timing of the isolation of Atlantic and Pacific tropical planktonic faunas resulting from the development of the Central American isthmus. Previous studies have suggested a late Miocene to middle Pliocene occurrence of this event. The Panama Basin (DSDP site 157) and the Colombian Basin (DSDP site 154A) share two early Pliocene biogeographic events: (1) great abundance of sinistral coiling Neogloboquadrina pachyderma at 4.3 m.y. ago at site 157 and 0.7 m.y. later at site 154A, and (2) a sinistral-to-dextral change in the coiling-direction preference in Pulleniatina 3.5 m.y. ago at both locations. Identification of these events farther to the east in the Venezuelan Basin (DSDP site 148) is complicated by insufficient lower Pliocene core recovery, but abundant sinistral N. pachydcrma appear to have extended far to the east in the Caribbean 3.6 m.y. ago; perhaps the early Pliocene abundance of this form is not indicative of cool water. The coiling-direction history and stratigraphic ranges of Pulleniatina became different in the Atlantic and Pacific Oceans during the early Pliocene; this is inferred to result from geographic isolation of the assemblages. Saito (1976) used the temporary disappearance of this genus from Atlantic waters at 3.5 m.y. ago to mark the closure of the Isthmus of Panama, but I show that in the Colombian Basin (site 154A) its disappearance was closer to 3.1 m.y. ago. This suggests the possibility of surface-water communication between the Atlantic and Pacific until that time.

(Table T1) Ages of white mica clasts in core samples of ODP Hole 210-1276A

Fifty-seven white mica clasts were separated from five samples taken from near the bases of turbidites ranging in age from early Albian to middle Eocene. Twenty two (39%) of the micas have ages between 260 and 340 Ma and five (9%) have older ages (~400-600 Ma). The former age range is characteristic of the North American Alleghenian orogeny and the Iberian Variscan orogeny. The latter range is characteristic of the North American Acadian orogeny and older basement rocks in the Grand Banks and Newfoundland areas. Both age ranges are present in the middle Eocene sample, but only the younger range occurs in the middle Albian sample. This difference could be a sampling artifact. If this is not the case, then the most likely explanation is that the Acadian-aged micas within the Meguma Zone underlying the Grand Banks were totally reset by Alleghenian reactivation of the zone, a feature which occurs extensively in Nova Scotia. The addition of Acadian-aged micas in the middle Eocene sample may reflect a change in sediment provenance as drainage systems unrelated to rift topography developed. With the exception of one clast dated at 186 Ma, the 12 other micas obtained from the upper Paleocene sample yielded ages between 55 and 74 Ma, with 7 falling within ±2 m.y. of the 57-Ma age of the sample indicated by the biostratigraphic age-depth plot for Site 1276. This, together with the volcaniclastic content of the sample, indicates an input from near-contemporaneous volcanism. The nearest known occurrences of near-contemporaneous late Paleocene volcanism that could have produced white micas are in Greenland and Portugal, some 2000 and 1500 km distant, respectively, from Site 1276 during the Paleocene. However, ages of volcanism in these areas indicate that they could probably not be sources of micas younger than 60 m.y., which suggests some as-yet unknown volcanic source in the North Atlantic area. Accumulation in the Grand Banks area of airborne-transported volcaniclastic material from eruptions of slightly different ages, followed by a single resedimentation event, could account for the spread of dates obtained from the sample. White micas from the lowermost Albian sample show a spread of ages between 37 and 284 Ma that is completely different from the age distribution pattern of the middle Albian and middle Eocene samples. The sample location is between, and at least 25 m above and below, two igneous sills dated at 98 and 105 Ma. The sills have narrow thermal aureoles and ages older than the youngest detrital micas in the sample. It is unlikely, therefore, that the spread of mica ages in the sample is due to partial resetting of ages caused by thermal effects associated with the intrusion of the sills. The resetting may have been associated with a longer lived thermal event.

Estimated chronologic ages of benthic microfossil events in ODP Site 105-647 (Table 1)

Benthic foraminifers were examined from the Paleogene of Ocean Drilling Program (ODP) Site 647 and Deep Sea Drilling Program (DSDP) Site 112 in the southern Labrador Sea. The Paleogene sequence of the deep Labrador Sea can be subdivided into seven assemblages, based on the ranges and relative abundance of characteristic taxa. The first occurrences (FOs) and last occurrences (LOs) of important benthic taxa are calibrated to a standard biochronology, by interpolating from our age model for Site 647. The biostratigraphy of Site 647 is used to improve the age estimates of Site112 cores. Fifteen microfossil events in Site 647 also are found in the sedimentary wedge along the Labrador Margin. A comparison of the probabilistic microfossil sequence from the Labrador Margin with that at Site 647 yields four isochronous benthic foraminifer LOs. Two new species are described from Sites 647 and 112: Hyperammina kenmilleri, Kaminski n.sp., and Ammodiscus nagyi Kaminski n.sp. Significant faunal turnovers are observed at the Ypresian/Lutetian and Eocene/Oligocene boundaries. The Ypresian/Lutetian boundary is characterized by a Glomospira-facies and is attributed to a rise in the CCD (carbonate compensation depth) associated with the NP14 lowstand in sea level. The Eocene/Oligocene boundary is delimited by the LO of Spiroplectammina spectabilis and Reticulophragmium amplectens. The change from an Eocene agglutinated assemblageto a predominantly calcareous assemblage in the early Oligocene took place gradually, over a period of about 4 Ma, but the rate of change accelerated near the boundary. This faunal turnover is attributed to changes in the preservationof agglutinated foraminifers, as delicate species disappeared first. Increasingly poorer preservation of agglutinated foraminifers in the late Eocene to earliest Oligocene reflects the first appearance of cool, nutrient-poor deep water in the southern Labrador Sea. The approximately coeval disappearance of agglutinated assemblages along the Labrador Margin was caused by a regional trend from slope to shelf environments, accentuated by the 'mid'-Oligocene lowstand in sea level.