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FIGURES Contents III Sea Level: In this report "sea level" refers to National Geodetic Vertical Datum of 1929 (NGVD of 1929) a geodetic datum derived from a general adjustment of the first-order level nets of both the United States and Canada, formerly called Sea Level Datum of 1929.

In 2014, samples from 37 monitoring wells at 17 locations, within or near oil fields, and one site >5 km from oil fields, in the Los Angeles Basin, California, were analyzed for dissolved hydrocarbon gas isotopes and abundances. The wells sample a variety of depths of an aquifer system composed of unconsolidated and semiconsolidated sediments under various conditions of confinement. Concentrations of methane in groundwater samples ranged from 0.002 to 150 mg/L—some of the highest concentrations reported in a densely populated urban area. The δ13C and δ2H of the methane ranged from −80.8 to −45.5 per mil (‰) and −249.8 to −134.9‰, respectively, and, along with oxidation‐reduction processes, helped to identify the origin of methane as microbial methanogenesis and CO2 reduction as its main formation pathway. The distribution of methane concentrations and isotopes is consistent with the high concentrations of methane in Los Angeles Basin groundwater originating from relatively shallow microbial production in anoxic or suboxic conditions. Source of the methane is the aquifer sediments rather than the upward migration or leakage of thermogenic methane associated with oil fields in the basin.

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The bryozoan species Bugula neritina contains the anticancer agent bryostatin. Bryostatin has been extracted from these sessile marine invertebrates since the late 1960s from the Gulf of California, Gulf of Mexico, as well as various locations on the eastern and western rims of the Pacific Ocean. In this work we are focusing on animals harvested in the Gulf of Mexico near Alligator Point (Florida). Using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) we measure the concentration of 70 elements in B. neritina, a sea squirt, and the sediment from the point of harvesting. This data has helped us generate an extraction process for marine natural products. Combining UV/VIS absorbance measurements with Matrix Assisted Laser Desorption Ionization-Time of Flight-Mass Spectrometer (MALDI-TOF-MS), we demonstrated that the specific form of bryostatin extracted is a function of the solvent. A 9.4T Fourier Transform-Ion Cyclotron Resonance (FT-ICR) mass spectrometer, whose sensitivity, mass accuracy, and resolving power allowed the exact empirical formulas of potential precursors of bryostatin to be identified, was employed. Finally we examine extracts of 14 marine species of the Gulf of Mexico, from the sand trout (Cynoscion arenarius) to chicken liver sponge (Chrondrilla nucula), all recently collected, which had shown some medicinal activity thirty years ago in a National Cancer Institute study. By the MALDI-TOF-MS, we were able to identify mass spectral features that correspond to different variations of the basic bryostatin structure, which raises the question if the bryozoans are the original source of bryostatin.