Geologic History of Florida

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Contributions to the Geology and Paleontology of the Canal Zone, Panama, and geologically related areas in central America and the West Indies. Part 11: The biologic character and geologic correlations of the sedimentary formations of Panama in their relation to the geologic history of Central America and the West Indies

The paper presents: 1) biologic summaries for each of the formations for which paleontologic data are available, with brief discussions of the geologic age; 2) geologic correlations of the formations and the distribution of their age-equivalents in Central America, the West Indies, and the southeastern United States; 3) an outline of the paleogeography of middle America. The biologic summaries are based on the paleontologic memoirs in this vol. by Messars. Howe, Berry, Chuchman, Jackson, Canu and Bassler and Pilsbry, Miss Rathbun and myself.

Tropical forest history of the Ecuadorian Andes over the last 34,000 years: preliminary results from pollen and oxygen isotope analyses of Trident 163-13 from the eastern equatorial Pacific [abstract]

EXTRACT (SEE PDF FOR FULL ABSTRACT): Pollen from the upper 2.75 m of a core taken 200 km west of the Golfo de Guayaquil, Ecuador (Trident 163-13, 3° S, 84° W, 3,000 m water depth) documents changes in Andean vegetation and climate of the Cordillera Occidental for ~17,000 years before and after the last glacial maximum.

Interactions between climatic variables controlling subalpine tree growth: implications for climatic history of the Sierra Nevada, California

EXTRACT (SEE PDF FOR FULL ABSTRACT): Tree-ring records from foxtail pine (Pinus balfouriana) and western juniper (Juniperus occidentalis) growing near tree line in the eastern Sierra Nevada, California, show strong correlations with summer temperature and winter precipitation. Response surfaces portraying tree growth as a function of summer temperature and winter precipitation indicate a strong interaction between these variables in controlling growth. ... Above average growth for both foxtail pine and western juniper from AD 1480 to 1570 can be interpreted as indicating an extended period of warm, moist conditions unequalled during the 20th century.

Holocene history of the El Niño phenomenon as recorded in flood sediments of northern coastal Peru

EXTRACT (SEE PDF FOR FULL ABSTRACT): The Holocene history of flooding in northern coastal Peru is believed to be a proxy record for the El Niño phenomenon. A recently completed set of 30 radiocarbon dates on overbank flood deposits and a tsunami deposit from the Casma region (Figure 1 and Table 1) establishes a chronology for the largest events that have occurred during the last 3500 years. ... The data presented here indicate that events much larger than the one in 1982-1983 may occur with a frequency of about once every 1000 years.

Sequence stratigraphy and sea-level history of Kangan formation in south pars field

Dehram group includes Faraghan, Dalan and Kangan formations. Kangan formation ages lower terias. That is one of the important reservoir rocks of southern Iran and Persian Gulf. In this research Kangan formation is studied in two A and B wells. Based on 75 studies on thin section, four carbonate litho acies association A, B, C, D with 12 subfacies are identified. A lithofacies association includes 4 subfacies: A1, A2, A3 and A4. B lithofacies association consists of 3 subfacies: B1, B2 and B3. C lithofacies association consists of 3 subfacies: C1, C2, C3 and D lithofacies association includes 2 subfacies: D1 and D2. On the base of studies lithofacies association of Kangan formations are formed in 3 environments of: Tidal Flat, Lagoon and Barrier Shore Complex in a Carbonated Platform Ramp type. Diagenetic processes have effected this formation. The most important Diagenetic processes are: Cementation, Anhydritization, Micrization, Neomorphism, Bioturbation, Dissolution, Compaction, Dolomitization and Porosity. Sequence staratigraphy studies were performed base on the vertical and horizontal relationship of lithofacies association and well logging in gamma ray and sonic type that causes the identification of two sedimentary sequences: First sedimentary sequence includes: Transgressive System Tract (TST) and High Stand System Tract (HST). The lower boundary of this sequence is in Sequence Boundary 1 (SB1) which shows unconformities of Dalan and Kangan that are Permian-terias unconformities. The upper boundary is in Sequence Boundary 2 (SB2) type that is identified by carbonate facies associated by anhydrite nodular. Second sedimentary sequence includes: TST and HST. Lower and upper boundaries of these sequences are both in SB2 type. The lower and upper boundary is made of carbonate facies with anhydrite nodular.

A history of the Connecticut River and its fisheries

(PDF contains 15 pages)

History of whaling in and near North Carolina

This study aims to reconstruct the history of shore whaling in the southeastern United States, emphasizing statistics on the catch of right whales, Eubalaena glacialis, the preferred targets. The earliest record of whaling in North Carolina is of a proposed voyage from New York in 1667. Early settlers on the Outer Banks utilized whale strandings by trying out the blubber of carcasses that came ashore, and some whale oil was exported from the 1660s onward. New England whalemen whaled along the North Carolina coast during the 1720s, and possibly earlier. As some of the whalemen from the northern colonies moved to Nortb Carolina, a shore-based whale fishery developed. This activity apparently continued without interruption until the War of Independence in 1776, and continued or was reestablished after the war. The methods and techniques of the North Carolina shore whalers changed slowly: as late as the 1890s they used a drogue at the end of the harpoon line and refrained from staying fast to the harpooned whale, they seldom employed harpoon guns, and then only during the waning years of the fishery. The whaling season extended from late December to May, most successfully between February and May. Whalers believed they were intercepting whales migrating north along the coast. Although some whaling occurred as far north as Cape Hatteras, it centered on the outer coasts of Core, Shackleford, and Bogue banks, particularly near Cape Lookout. The capture of whales other than right whales was a rare event. The number of boat crews probably remained fairly stable during much of the 19th century, with some increase in effort in the late 1870s and early 1880s when numbers of boat crews reached 12 to 18. Then by the late 1880s and 1890s only about 6 crews were active. North Carolina whaling had become desultory by the early 1900s, and ended completely in 1917. Judging by export and tax records, some ocean-going vessels made good catches off this coast in about 1715-30, including an estimated 13 whales in 1719, 15 in one year during the early 1720s, 5-6 in a three-year period of the mid to late 1720s, 8 by one ship's crew in 1727, 17 by one group of whalers in 1728-29, and 8-9 by two boats working from Ocracoke prior to 1730. It is impossible to know how representative these fragmentary records are for the period as a whole. The Carolina coast declined in importance as a cruising ground for pelagic whalers by the 1740s or 1750s. Thereafter, shore whaling probably accounted for most of the (poorly documented) catch. Lifetime catches by individual whalemen on Shackleford Banks suggest that the average annual catch was at least one to two whales during 1830·80, perhaps about four during the late 1870s and early 1880s, and declining to about one by the late 1880s. Data are insufficient to estimate the hunting loss rate in the Outer Banks whale fishery. North Carolina is the only state south of New Jersey known to have had a long and well established shore whaling industry. Some whaling took place in Chesapeake Bay and along the coast of Virginia during the late 17th and early 18th centuries, but it is poorly documented. Most of the rigbt whales taken off South Carolina, Georgia, and northern Florida during the 19th century were killed by pelagic whalers. Florida is the only southeastern state with evidence of an aboriginal (pre-contact) whale fishery. Right whale calves may have been among the aboriginal whalers' principal targets. (PDF file contains 34 pages.)

Age, growth and life history of Klamath River Basin steelhead trout (Onchorhynchus mykiss irideus) as determined from scale analysis

Adult steelhead (Oncorhynchus mykiss irideus) scales were analyzed from eight fall-run, two spring-run, and one winter-run stocks within the Klamath-Trinity River system, from 1981 through 1983, to provide basic information on age, growth, and life history. The higher degree of half-pounder occurrence of upper Klamath River steelhead stocks (86.7 to 100%) compared to Trinity River steelhead stocks (32.0 to 80.0%) was the major life history difference noted in scale analysis. Early life history was similar for all areas sampled with most juveniles (86.4%) remaining in freshwater during the first two years of life before migrating to sea. Repeat spawning ranged from 17.6 to 47.9% for fall-run, 40.0 to 63.6% for spring-run, and 31.1% for winter-run steelhead. Mean length of adults at first spawning was inversely related to percent half-pounder occurrence in each stock. Ages of returning spawners, back calculated lengths at various life stages, and growth information are presented. (PDF contains 22 pages)

A 30-Year History of Tide and Current Measurements in Elkhorn Slough, California

Elkhorn Slough was first exposed to direct tidal forcing from the waters of Monterey Bay with the construction of Moss Landing Harbor in 1946. Elkhorn Slough is located mid-way between Santa Cruz and Monterey close to the head of Monterey Submarine Canyon. It follows a 10 km circuitous path inland from its entrance at Moss Landing Harbor. Today, Elkhorn Slough is a habitat and sanctuary for a wide variety of marine mammals, fish, and seabirds. The Slough also serves as a sink and pathway for various nutrients and pollutants. These attributes are directly or indirectly affected by its circulation and physical properties. Currents, tides and physical properties of Elkhorn Slough have been observed on an irregular basis since 1970. Based on these observations, the physical characteristics of Elkhorn Slough are examined and summarized. Elkhorn Slough is an ebb-dominated estuary and, as a result, the rise and fall of the tides is asymmetric. The fact that lower low water always follows higher high water and the tidal asymmetry produces ebb currents that are stronger than flooding currents. The presence of extensive mud flats and Salicornia marsh contribute to tidal distortion. Tidal distortion also produces several shallow water constituents including the M3, M4, and M6 overtides and the 2MK3 and MK3 compound tides. Tidal elevations and currents are approximately in quadrature; thus, the tides in Elkhorn Slough have some of the characters of a standing wave system. The temperature and salinity of lower Elkhorn Slough waters reflect, to a large extent, the influence of Monterey Bay waters, whereas the temperature and salinity of the waters of the upper Slough (>5 km from the mouth) are more sensitive to local processes. During the summer, temperature and salinity are higher in the upper slough due to local heating and evaporation. Maximum tidal currents in Elkhorn Slough have increased from approximately 75 to 120 cm/s over the past 30 years. This increase in current speed is primarily due to the change in tidal prism which has increased from approximately 2.5 to 6.2 x 106 m3 between 1956 and 1993. The increase in tidal prism is the result of both 3 rapid man-made changes to the Slough, and the continuing process of tidal erosion. Because of the increase in the tidal prism, the currents in Elkhorn Slough exhibit positive feedback, a process with uncertain consequences. [PDF contains 55 pages]

Toward a measure of social-ecological resilience for human communities

The purpose of this essay is to clarify the theoretical understanding of the concept of resilience in order to explore problems surrounding the empirical measurement and application of the concept, as well as to examine strategic examples of empirical measures and policy applications in the literature of several disciplines, fields, and professions. The examination of resilience occurs in two streams: one conceptual and one methodological. At the conceptual level, the focus will be on definitions, distinctions between resilience and related concepts, and the theoretical frameworks that underlie usage of the concept. At the empirical level, the examination of resilience will be centered on the methodological challenges associated with research on resilience as well as previous attempts to operationalize and measure resilience. (PDF contains 4 pages)

Limnology in Sicily: A history of fresh waters surrounded by the sea

The aim of this short article is to trace the history of limnology in Sicily, from the end of the last century up to the present, and pay a little homage to a scientist to whom limnology is deeply indebted: G.E. Hutchinson. Due to its insular and climatic conditions, Sicily is characterised by a drainage network formed by numerous short, torrent-like rivers, and by a few small, natural lakes. The geological characteristics of the island strongly condition the quality of these small waterbodies which generally have surface areas of less than 0.2 km super(2). The earliest observations on Sicilian lentic waters go back more than a century; in particular, at the end of the 19th century, some of the issues regarding the natural lakes had already been brought into focus. Subsequent studies on natural waterbodies concentrated on the geomorphology of landslide lakes or lakes created by the dissolution of the gypsum tableland. However, many of the waterbodies no longer exist because of land reclamation which took place up to the first half of the 1950s. During the last 35 years, there has been a notable increase in limnological publications. In addition, these studies show a more careful and integrated approach to the limnological aspects of waterbodies, compared with the early studies.

A brief history of the scientific study of tropical African inland waters

An account is given of a study of African tropical waters, drawing on the personal experiences of the author. Reviewing developments since 1900, the author examines the way in which research has developed and the influence the changes in the policitcal map of Africa, in particular the change from colonial rule, has had on research.

Application of diatom analysis for the study of the history of the lakes of north-west USSR. [Translation from: Istoriya Ozer; Trudy Vses.Simp.Vilnius p1-7. Vilnius, 1970.]

During late - and post-glacial times lakes played a leading role in the development of the landscape of the North-west European part of USSR. A variety of geographic circumstances created great variegation of natural conditions in lakes and determined the composition of their diatoms. The basic stages of the development of the diatom flora of lakes are linked with general climatic changes. The deepwater regions of large periglacial lakes of the North-west USSR are inhabited by plankton diatoms of the genera Melosira and Cyclotella. Diatom analysis is further applied for the study of the history of the lakes of north-west USSR.